Darriwilian (Middle Ordovician) conodonts from the ...

1 downloads 0 Views 2MB Size Report
Ordovician) conodonts from the Maruia-Springs Junction area, New Zealand. ... distribution of the Buller and Takaka Terranes, the Anatoki Fault that separates ...
Darriwilian (Middle Ordovician) conodonts from the MaruiaSprings Junction area, New Zealand YONG YI ZHEN, ROGER A. COOPER, JOHN E. SIMES & IAN G. PERCIVAL ZHEN, Y.Y., COOPER, R.A., SIMES, J.E. & PERCIVAL, I.G., 2011:12:23. Darriwilian (Middle Ordovician) conodonts from the Maruia-Springs Junction area, New Zealand. Memoirs of the Association of Australasian Palaeontologists 42, 285-319. ISSN 0810-8889. A diverse conodont fauna of 28 species has been recovered from the Sluice Box Formation, exposed in the Maruia-Lake Daniels-Springs Junction area at the southernmost extension of the fossiliferous Lower Palaeozoic terranes in the south west Nelson region of New Zealand’s South Island. The fauna is characterised by several zonal index species including important age-diagnostic pectiniform taxa such as Pygodus serra, P. anitae, Eoplacognathus suecicus, Yangtzeplacognathus foliaceus, Histiodella kristinae, Dzikodus tablepointensis, Polonodus newfoundlandensis and P. clivosus. All except P. serra are reported for the first time from New Zealand, and indicate a middle to late Darriwilian age (from the E. suecicus Zone to the Y. foliaceus Subzone of the basal P. serra Zone) for the assemblage. Biostratigraphically the Maruia conodont fauna is the most well constrained known from this time interval in eastern Australia and New Zealand, and is comparable with contemporaneous offshore shelf-edge to slope assemblages previously documented from Thompson Creek in NW Nelson and from central New South Wales. Yong Yi Zhen ([email protected]), Palaeontology Section, Australian Museum, 6 College St, Sydney NSW 2010, Australia; Ian G. Percival ([email protected]. au), Geological Survey of New South Wales, Department of Trade & Investment, W.B. Clarke Geoscience Centre, 947-953 Londonderry Road, Londonderry NSW 2753, Australia; Roger A. Cooper ([email protected]) and John E. Simes ([email protected]), GNS Science, P.O. Box 30 368, Lower Hutt, New Zealand. Received 31 October, 2011. Keywords: Conodonts, Middle Ordovician, Darriwilian, New Zealand, biostratigraphy.

ORDOVICIAN conodont faunas have previously been recorded from New Zealand from several stratigraphic levels in limestones confined to the northwest corner of the South Island (Fig. 1), all within rocks of the Takaka Terrane. Early Ordovician forms were first described by Cooper & Druce (1975) from the middle and upper parts of the Summit Limestone. These faunas were reassessed by Wright et al. (1994), who revised the age of the lower Summit Limestone as latest Tremadocian, and assigned an earliest Floian age to the uppermost exposed Summit Limestone at Mount Patriarch. Undescribed conodonts from the Summit Limestone in the Cobb Valley indicate an age range of latest Cambrian to Middle Ordovician (Darriwilian) for this formation (Cooper & Bradshaw 1986; Cooper 1989). Middle Ordovician conodonts from allochthonous limestone at Thompson Creek near the Paturau River were first reported by Wright (1968). This diverse fauna, including amongst other species the biostratigraphically important taxa Histiodella holodentata, Paroistodus originalis,

P. horridus, Periodon macrodentatus, Costiconus ethingtoni and Venoistodus balticus, was fully described by Zhen et al. (2009) who determined a middle Darriwilian (late Da2 to mid Da3) age. From its age and lithology, the Thompson Creek lens (Zhen et al. 2009; Percival et al. 2009) is interpreted as equivalent to the upper part of the Summit Limestone. Simes (1980) recorded latest Darriwilian to earliest Sandbian conodonts, including Pygodus anserinus, from the upper part of the Arthur Marble 1 at Mount Owen. The Lower Palaeozoic succession in the Maruia-Lake Daniels area was first described by Farmer (1967) and the formation names used here generally follow his scheme. Three stratigraphic units are recognised; in upward sequence they are the Thompsons Flat Formation, Sluice Box Formation and Alfred Formation (Figs 2 and 3). They represent the southernmost extension of the Takaka Terrane west of the Alpine Fault (Cooper 1989). Graptolites were first reported from float boulders in the Alfred River by Wellman (1962). Conodonts, brachiopods, graptolites,

286

AAP Memoir 42 (2011)

Figure 1. Simplified Palaeozoic geology of the northwestern part of the South Island, New Zealand, showing distribution of the Buller and Takaka Terranes, the Anatoki Fault that separates them, and localities mentioned in text (after Cooper & Tulloch 1992, fig. 1). WSB, CSB and ESB in legend are abbreviations of Western, Central and Eastern Sedimentary Belts, respectively. Area of the detailed geological map (Fig. 3) is situated immediately east of the town of Springs Junction, between the Anatoki and Alpine faults.

and rare trilobites were obtained by Simes and Cooper in the course of mapping the area (Cooper unpublished, 1972-1988). Conodonts and brachiopods in the Sluice Box Formation establish an age range for this unit from late Cambrian (Furongian) to Darriwilian. Only the most prolific conodont faunas, of middle to late

Darriwilian age, are described in the present paper. Other stratigraphic levels, including upper Cambrian, Lower Ordovician, and latest Middle Ordovician – the latter represented in the overlying Alfred Formation – are relatively poor in conodonts and will be documented elsewhere. Many biostratigraphically important species are

AAP Memoir 42 (2011)

287

Figure 2. Stratigraphic columns diagrammatically illustrating relationships amongst units of the Buller and Takaka terranes. Within the Takaka Terrane, formations of the western part of the terrane (Central Sedimentary Belt of Cooper 1979, 1989) are based on the Mount Patriarch area, those of the eastern part of the terrane (Eastern Sedimentary Belt) are based on the Mount Owen and Mount Arthur areas. Stratigraphy of the Maruia area is as described here. Fossiliferous horizons are indicated by G (graptolites), C (conodonts), T (trilobites), B (brachiopods).

recognised in the Maruia material, several for the first time from New Zealand, making this a significant contribution to constraining age relationships within Takaka Terrane rocks and enabling precise correlations with sequences in eastern Australia and further afield.

REGIONAL GEOLOGICAL SETTING Lower Palaeozoic rocks of northwest Nelson and Westland (Fig. 1) occupy two lithologically distinct terranes (Cooper 1989) – the Takaka and Buller terranes – separated by a north-south trending zone of transcurrent and thrust faulting called the Anatoki Fault (Jongens 2006). The

288

AAP Memoir 42 (2011)

Figure 3. Detailed geology of the Maruia-Lake Daniells area based on unpublished mapping by Cooper and Simes, showing location of main fossil localities discussed in this report and their NZ Fossil Record File numbers. Separating Thompsons Flat Formation from Sluice Box Formation around the Thompsons Flat Antiform is the Daniells Fault, indicated by tick marks.

stratigraphy and structure of the Takaka Terrane is complex, with at least 12 discrete faultbounded slices recognised, each with a distinctive stratigraphic succession. A Cambrian arc complex (Münker & Cooper 1999) is overlain by an

Ordovician carbonate-dominated sedimentary succession, followed by Silurian quartz arenite. The Maruia Ordovician sequence resembles that of the western part of the Takaka Terrane to the north (Central Sedimentary Belt of Cooper 1979)

AAP Memoir 42 (2011) at Cobb Valley and Mount Patriarch. STRATIGRAPHY AND STRUCTURE The oldest strata in the Maruia segment of the Takaka Terrane are inferred to be those mapped as Thompsons Flat Formation. They are composed of dolomitic thin-bedded mudstone and ankeritic sandstone with abundant interlayered felsic volcanic rocks, monomict and polymict conglomerate and dark muddy diamictite. Fossils are unknown. The rocks were correlated with the Haupiri Group of northwest Nelson by Nathan et al. (2002) on their general lithology and composition. The association of laminated siltstone, polymict conglomerate and interlayered felsic volcanics certainly resembles that of the Heath Creek Beds of Cobb Valley, of Floran to Undillan (Drumian) age (Münker & Cooper 1999). However, distinctive middle to late Cambrian Haupiri Group formations such as Lockett Conglomerate and Tasman Formation are lacking in the Maruia district. The Thompsons Flat Formation is here tentatively regarded as of middle Cambrian (Series 3) age. These rocks form a ‘lower plate’, separated from an ‘upper plate’ by a major low-angle fault, here termed the Daniells Fault. The Daniells Fault is exposed only in a small disused quarry on the true right bank of the Maruia River, 3 kms NW of Springs Junction. It is inferred to be a large-scale extensional structure. The upper plate sequence, which is subparallel to the fault, consists of the Sluice Box Formation overlain by the Alfred Formation. The fault truncates the base of the Sluice Box Formation and the oldest preserved strata above the fault therefore range from late Cambrian to Darriwilian, along the length of the fault. Based on the mapped distribution and structure of the Sluice Box Formation (Fig. 3), the Daniells Fault (along with the whole upper plate), has been folded into a north-plunging antiform. The fault and antiform were subsequently disrupted by many NE trending faults, most of which pre-date the Miocene Maruia Formation. The upper plate units are generally less tectonised than the lower plate units. Sluice Box Formation No complete sections are exposed through the limestone, and its internal stratigraphy is inferred from numerous partial sections. The lower part of the formation consists of dark flaggy micritic limestone and calcareous shale that varies in thickness and lithology. In the southern part of the mapped area it reaches approximately 180 m in thickness in the eastern antiform limb but in the western limb it is excluded altogether by the Daniells Fault. To the north, in the first true

289

right tributary of Station Creek downstream from Thompsons Flat (‘Gorge Creek’), where its thickness is possibly much greater, it contains abundant thin interbedded chert layers and is less calcareous than to the south. Soft sediment deformation, including probable slump folds, is common. Late Cambrian trilobites, conodonts and brachiopods are present in the headwaters of Station Creek (locality M31/f1) representing the oldest strata in the upper plate. The upper part of the Sluice Box Formation is about 180 m thick in the upper reaches of Station Creek, increasing in thickness to the north in Gorge Creek. It consists of pale coloured micritic, partially recrystallised massive to flaggy limestone with rare interbedded shale. Oolite-rich lenses are common and lenses of sparry limestone are found at several localities, particularly near the upper boundary. Rich microfossil assemblages have been recovered from several of these sparry layers. Conodonts described herein include (amongst other species) Eoplacognathus suecicus, Yangtzeplacognathus foliaceus, Histiodella kristinae, Dzikodus tablepointensis, Polonodus newfoundlandensis, P. clivosus, Periodon macrodentatus, Costiconus ethingtoni, Ansella jemtlandica, Paroistodus horridus, Pygodus serra and P. anitae. Several middle to late Darriwilian zones and subzones may be represented in these faunas, which span the interval from the E. suecicus Zone to the Y. foliaceus Subzone of the basal P. serra Zone. Alfred Formation Dark, strongly cleaved siltstone and sandstone that overlies the Sluice Box Formation on both flanks of the Thompsons Flat antiform is termed the Alfred Formation. The lower part of the formation consists of dark calcareous siltstone with rare nodules and bands of limestone. Soft sediment deformation (possibly due to slumping) is common. A black shale band less than 15 m above the base in Gorge Creek has yielded poorly preserved graptolites including Dicellograptus and Dicranograptus of latest Darriwilian to Gisbornian age. Conodonts from the limestone lenses include Periodon aculeatus, indicating a late Darriwilian age. The upper part of the formation consists of dark coloured strongly cleaved shale, with alternating quartzose sandstone beds. Poorly preserved ageindeterminate graptolites reported by Wellman (1962) are probably from this part. AGE AND CORRELATION Some 1495 identifiable conodont specimens documented in this contribution were recovered from 25 samples (Table 1) from the Sluice Box

4

6

4

2 17

1 1

73

1

3

3 10 12 3 16 1

6 3 3

3

1

1 5 27 14 14 4 9 23 15 32 22

5 2 11

1 1

40 25 57 3

2

1 3

1 6

5 3

1 1 6

4 7

4

2

7 2 8

2

1

1

9

7 3

2 10 4 1 35 1 2 2 1 6 148 49 43 93 38 61 74 27 6

1 7

84 65 80 1

M31/f44

M31/f45

M31/f46

CN579

CN578

CN577

CN574

M31/f48

M31/f43

25

L31/f87

M31/f36

3 2

CN580

M31/f34

CN495

M31/f22

3

M31/f31

M31/f21

CN480

7 1

2 1

CN493

M31/f14

CN479

3 19

CN487

M31/f14

CN507

19

M31/f24

M31/f7

CN343

L31/f97

2 18

M31/f7

L31/f65

CN555

8

CN489a

L31/f45

CN498

7

L31/f98

L31/f45

CN463

2 5 1

6 11 1

CN323

L31/f45

CN558c

8

CN553

L31/f2

3

CN482

Ansella jemtlandica Aurilobodus sp. Baltoniodus sp. Costiconus ethingtoni Drepanodus reclinatus Drepanoistodus sp. Dzikodus tablepointensis Erraticodon? sp. Eoplacognathus suecicus Gen. et sp. indet. Histiodella kristinae Panderodus gracilis Paroistodus horridus Periodon macrodentatus Polonodus clivosus Polonodus newfoundlandensis Polonodus sp. Prioniodus sp. Protopanderodus cooperi Protopanderodus? nogamii Protopanderodus varicostatus Protopanderodus sp. Pygodus anitae Pygodus serra Pygodus? sp. Spinodus spinatus Yangtzeplacognathus foliaceus Yangtzeplacognathus sp. Total

CN558a

Samples Conodont species

CN497

Locality  

CN596a

AAP Memoir 42 (2011)

290

9

5

9

3

12

Total 96 2 3 2 1 1 7 55 46 53 7 3 3 58 17 18 4 304 1 5 7 19 1 1 38 1 1 3 5 1 2 1 1 8 21 14 2 98 8 29 2 1 51 2 45 23 464 11 11 14 1 22 26 3 2 2 19 3 6 3 1 4 2 2 42 10 1 5 29 1 5 42 11 59 6 8 1 1 3 1 2 8 17 3 5 78 17 20 12 92 7 91 152 16 28 29 65 105 154 29 57 1495

Table 1. Distribution of identifiable conodont species recovered from the 25 samples studied.

Formation. They are opaque black with a CAI of 5, indicating a high level of maturation (Epstein et al. 1977). The preservation of the conodont specimens varies from reasonably well preserved to rather strongly deformed or poorly preserved. 28 species are recognised, including Ansella jemtlandica, Aurilobodus sp., Baltoniodus sp., Costiconus ethingtoni, Drepanodus reclinatus, Drepanoistodus sp., Dzikodus tablepointensis, Erraticodon? sp., Eoplacognathus suecicus, gen. et sp. indet., Histiodella kristinae, Panderodus gracilis, Paroistodus horridus, Periodon macrodentatus, Polonodus clivosus, Polonodus newfoundlandensis, Polonodus sp., Prioniodus sp., Protopanderodus cooperi, Protopanderodus? nogamii, Protopanderodus varicostatus, Protopanderodus sp., Pygodus anitae, Pygodus serra, Pygodus? sp., Spinodus spinatus, Yangtzeplacognathus foliaceus and Yangtzeplacognathus sp. (Table 1). Occurrence of H. kristinae in two samples (CN558a and CN463 [both from L31/f45]) supports correlation with the E. suecicus Zone of the Baltoscandian conodont succession. Co-occurrence of E. suecicus and P. anitae in three samples (CN579, CN578, and CN487 [M31/f44, M31/f45 and M31/f31 respectively] see Table 1) suggests correlation with the P. anitae Subzone (upper E. suecicus Zone) of the Baltoscandian conodont succession, while co-occurrence of P. serra and

Y. foliaceus in three samples (CN575, CN553 and CN487 [M31/f47, L31/f98 and M31/f31 respectively] see Table 1) indicates an age of the ensuing Y. foliaceus Subzone (earliest P. serra Zone). However, E. suecicus, P. anitae, P. serra and Y. foliaceus co-occur in one of the most productive samples (CN487 [M31/f31], see Table 1). Such an association of species with normally non-overlapping ranges is problematic, suggesting that this may be a composite sample derived from reworked sediments. Alternatively, the stratigraphical ranges of both P. anitae and E. suecicus may need to be revised as extending well into the Y. foliaceus Subzone (P. serra Zone). Overall, a middle to late Darriwilian age, ranging from the E. suecicus Zone to the Y. foliaceus Subzone of the P. serra Zone, is postulated for the conodont faunas in the upper part of the Sluice Box Formation. Bergström (1971a) originally established the E. suecicus Subzone and Y. foliaceus Subzone along with three other subzones (E. reclinatus, E. robustus and E. lindstroemi subzones) as subdivisions of the P. serra Zone. The lowest confirmed occurrence of P. serra was recorded from the Seby Limestone in the Middle Ordovician of Sweden, but it was also reported as doubtfully occurring in the underlying Segerstad Limestone and Skärlöv Limestone in association with E. suecicus (Bergström 1971a, p. 91, figs

AAP Memoir 42 (2011) 4-5). Subsequently, the E. suecicus Subzone was excluded from the P. serra Zone (Bergström 1971b, p. 179, figs 1-2; Bergström et al. 1974; Jaanusson & Bergström 1980) with E. suecicus becoming the index species for the conodont zone underlying the P. serra Zone (Löfgren 1978; Bergström 1983). Pygodus serra had a wide geographical distribution in the late Middle Ordovician, being known from Europe, North America, Argentina, China, southeastern Asia, Australia and New Zealand as a key taxon for precise international correlation of this time interval (stage slice DW3, see Bergström et al. 2009). Löfgren (1978) indicated that P. serra made its first appearance in the lower part of the Y. foliaceus Subzone, slightly higher than the first appearance of Y. foliaceus in Jämtland. Zhang (1998c, fig. 5) and Zhang & Sturkell (1998, figs 3-4) confirmed the earliest occurrence of P. serra in the middle part of the Seby Limestone (Y. foliaceus Subzone, sample Lu 2.37) some 35 cm above the last appearance of P. anitae (sample Lu 2.72) in the Lunne Section of Sweden. In the biostratigraphic revision of the Kårgärde succession (the reference section of the P. serra Zone) in the Siljan region of southcentral Sweden, Bergström (2007b) recorded the lowest occurrence of P. serra at the top of the Seby Linestone coinciding with the lowest occurrence of Eoplacognathus reclinatus, the zonal index for the second subzone of the P. serra Zone. Based on more recent studies in Sweden, P. serra is confirmed to range from the lower part of the Y. foliaceus Subzone to the lower part of the P. anserinus Zone (Sweet 1988, chart 2; Zhang 1998c; Zhang & Sturkell 1998), with the base of the P. serra Zone defined by the first appearance (FAD) of Y. foliaceus (Löfgren 1978, p. 32) rather than the first appearance (FAD) of P. serra as Bergström (1971a) originally proposed. Specimens of P. serra recovered from three samples in the Maruia material (Fig. 14LN) exhibit a distally expanded platform and may represent the stratigraphically earliest form of this species (see Zhang 1998c, fig. 2). As stated above, E. suecicus was initially taken as the index species for the basal subzone of the P. serra Zone (Bergström 1971a; Lindström in Ziegler 1977), and later for the separate zone underlying the P. serra Zone (Bergström, 1983). Although E. suecicus is widely distributed in Baltoscandia (Bergström 1971a; Viira, 1967, 1974; Zhang 1999), North America (Harris et al. 1979; Pyle & Barnes 2003), China (An & Zheng 1990; Zhang 1998a) and Australasia (this study) as a biostratigraphically important zonal index, its species definition and morphological variation were interpreted rather differently

291

until the publication of a detailed study of this species by Zhang (1999). Zhang (1998a, table 1) recognised the E. suecicus Zone at the top part of the Guniutan Formation in South China. Eoplacognathus suecicus was recorded in the Majiagou Formation and age equivalent units in North China by An & Zheng (1990) and An et al. (1983), although Zhang (1999) questioned the assignment of the specimens illustrated as E. suecicus by An et al. (1983, pl. 27, figs 1-11). Löfgren (1978) subdivided the E. suecicus Zone into two subzones, the E. suecicus-Scalpellodus gracilis Assemblage Subzone in the Aserian, and the E. suecicus-Panderodus sulcatus Assemblage Subzone in the upper Kundan of Baltoscandia. Zhang (1999) pointed out that those upper Kundan specimens without the secondary denticle row on the posterolateral process, which were described and illustrated by Löfgren (1978, pl. 15, figs 16-17) as belonging to E. suecicus, should be assigned to the stratigraphically latest form of E. pseudoplanus. Zhang (1998c) also subdivided the E. suecicus Zone into two subzones, the lower Pygodus lunnensis Subzone and the upper Pygodus anitae Subzone. Zhang (1998c, fig. 5; 1999, fig. 1) and Viira (2011, fig. 2) confined the E. suecicus Zone to the Aserian and correlated it with the Segerstad Limestone in the Lunne section of Jämtland of central Sweden, whereas Bergström (2007b, figs 5-6) correlated it with the Segerstad Limestone and lower-middle parts of the overlying Skärlöv Limestone in the Kårgärde succession of the Siljan region, southcentral Sweden. Löfgren (1978) reported the cooccurrence of both Y. foliaceus and E. suecicus in the lowermost part of the Y. foliaceus Subzone in Jämtland of Sweden. Zhang & Sturkell (1998, fig. 3) also recorded the co-occurrence of E. suecicus, P. anitae and Y. foliaceus at the base of the Y. foliaceus Subzone (middle part of the Skärlöv Limestone) in the Kullstaberg and Lunne sections of Jämtland, central Sweden, but co-occurrence of P. serra with either E. suecicus or P. anitae was not reported previously. Pygodus anitae was recorded from Baltoscandia (Bergström 1983; Zhang 1998c; Zhang & Sturkell 1998), Argentina (Ottone et al. 1999; Albanesi & Ortega 2002; Ortega et al. 2007), North China (An & Zheng 1990), Tarim (Zhao et al. 2000) and New Zealand (this study), with a stratigraphic range confined to the upper E. suecicus Zone and the lower part of the Y. foliaceus Subzone. Yangtzeplacognathus foliaceus was previously reported from Baltoscandia (Fåhraeus 1966; Bergström 1971a; Zhang 1998b, 1999; Viira et al. 2001; Viira 2011), North America (Bergström 1971a, 1973), and South China (Chen & Zhang 1984a, b; Zhang 1998a), as a biostratigraphically

292

AAP Memoir 42 (2011)

Figure 4. Ansella jemtlandica (Löfgren, 1978). A-B, M element; A, CNP1203, CN574, anterior view (IY176019), B, CNP1204, CN574, posterior view (IY176-020). C-E, Sa element; C, CNP1205, CN574, lateral view (IY176-024); D-E, CNP1206, CN580, D, posterior view (IY176-007), E, lateral view (IY176-008). F-G, Sb element; F, CNP1207, CN578, outer lateral view (IY174-004); G, CNP1208, CN580, inner lateral view (IY176-011). H-J, Sc element; H, CNP1209, CN578, inner lateral view (IY174-006); I, CNP1210, CN578, outer lateral view (IY174-005); J, CNP1211, CN487, inner lateral view (IY179-001). K-M, Pa element; K, CNP1212, CN574, outer lateral view (IY196-021); L, CNP1213, CN579, inner lateral view (IY175-012); M, CNP1214, CN580, outer lateral view (IY176-005). N-P, Pb element; N, CNP1215, CN574, inner lateral view (IY176-018); O, CNP1216, CN578, inner lateral view (IY174-003); P, CNP1217, CN580, outer lateral view (IY176-003). Scale bars 100 μm.

293

AAP Memoir 42 (2011) important zonal index. The base of the Y. foliaceus Subzone (basal part of the P. serra Zone) is marked by the first appearance (FAD) of Y. foliaceus, which has a stratigraphic range from the upper Skärlöv Limestone to the basal Folkeslunda Limestone in Sweden (Bergström 1971a, p. 95, fig. 4). The Y. foliaceus Subzone was correlated with the lower part of the Lasnamägian Stage in Sweden (Lindström in Ziegler 1977, p. 134; Zhang 1998c, fig. 3; Viira 2011, fig. 2). Zhang (1998a, table 1) recognised the Y. foliaceus Zone in the basal Miaopo Formation that is widely distributed in South China. Occurrence of Y. foliaceus in the Maruia material is the first record of this zonal index species in the Australasian region, and is crucial in precise correlation with well established Middle Ordovician conodont successions in Baltoscandia and South China. In the reference section of the Histiodella kristinae Zone in western Newfoundland (see Stouge 1984), H. kristinae was recorded as extending from the top of the lower member of the Table Head Formation and ranging through the entire middle member of that unit in association with Dzikodus tablepointensis and Polonodus clivosus. Polonodus newfoundlandensis (also found in the Maruia fauna) occurs immediately below the first appearance of H. kristinae in the Table Head Formation. Histiodella kristinae is an important zonal index for regional correlation, being widely distributed in North America (Barnes & Poplawski 1973; Landing 1976; Stouge 1984; Nowlan & Thurlow 1984), Europe (Dzik 1994; Rasmussen 2001; Löfgren 2004; Viira 2011), Argentine Precordillera (Lehnert 1995; Heredia et al. 2005; Heredia, pers. comm. 2010; Albanesi, pers. comm. 2011), South China (Ni 1981; Ding et al. in Wang 1993; Zhang 1998a), North China (Wang & Lou 1984; An & Zheng 1990), Tarim (Wang & Zhou 1998; Zhao et al. 2000; Du et al. 2005; Zhen et al. 2011), and New Zealand (this study). Stouge (1984) correlated the H. kristinae Zone with the E. suecicus Zone of the Baltoscandian succession. Based on graptolite and conodont studies from South China, Chen et al. (2006) correlated the H. kristinae Zone with the upper part of the E. pseudoplanus Zone and the E. suecicus Zone of the Baltoscandian succession. In the Huangnitang Section of Zhejiang Province, South China, H. kristinae was reported occurring in the upper part of the Hulo Formation within the Pterograptus elegans graptolite Zone (Chen et al. 2006). Bergström et al. (2009) suggested that the top of the H. kristinae Zone could be approximately correlated with the base of the P. serra Zone. Therefore the occurrence of H. kristinae associated with D. tablepointensis, P. newfoundlandensis, P. clivosus and P. horridus

in the Maruia samples (Table 1) supports a correlation with the E. suecicus Zone of the Baltoscandian succession. SYSTEMATIC PALAEONTOLOGY (Zhen) All illustrations shown in Figures 4 to 18 are SEM photomicrographs of conodonts captured digitally. Specimen numbers are prefixed CNP; collection numbers are prefixed CN; and fossil localities, which may have yielded repeat collections, are prefixed with the 1:50 000 sheet number - M31 or L31- and are shown in the geological sketch map (Fig. 3). Collections are related to their localities in Table 1. 172 figured specimens bearing the prefix CNP (CNP 1203 – CNP 1274) are deposited in the palaeontological collections of the New Zealand Institute of Geological and Nuclear Sciences, Lower Hutt. Sample localities are shown in Figure 3; further details of these sites were provided earlier in the paper. Eight conodont species, including Baltoniodus sp. (Fig. 5M), Drepanoistodus sp. (Fig. 6L-N), Gen. et sp. indet. (Fig. 9F), Panderodus gracilis (Branson & Mehl, 1933) (Fig. 9C-E), Polonodus sp. (Fig. 11I-L), Prioniodus sp. (Fig. 11M-O), Protopanderodus? nogamii (Lee, 1975) (Fig. 12F-I) and Pygodus? sp. (Fig. 8K-L) are rare and documented by illustration only. Class CONODONTA Pander, 1856 Ansella Fåhræus & Hunter, 1985 Type species. Belodella jemtlandica Löfgren, 1978. Ansella jemtlandica (Löfgren, 1978) (Fig. 4) 1978 Belodella jemtlandica; Löfgren, p. 46, pl. 15, figs 1-8, fig. 24A-D. 1985 Ansella jemtlandica (Löfgren); Fåhræus & Hunter, p. 1173-1175, pl. 1, figs 1-5, 9, pl. 2, fig. 12a-b, text-fig. 1. 2004a Ansella jemtlandica (Löfgren); Zhen & Percival, p. 84-86, fig. 5A-Q (cum syn.). 2004b Ansella jemtlandica (Löfgren); Zhen & Percival, fig. 4A-G. 2007 Ansella jemtlandica (Löfgren); Ortega et al., fig. 6O. 2009b Ansella jemtlandica (Löfgren); Zhen et al., p. 29-30, fig. 2A-I. 2011 Ansella jemtlandica (Löfgren); Zhen et al., p. 214, fig. 4A-O (cum syn.). Material. 96 specimens recovered from 10 samples (see Table 1). Remarks. Fåhræus & Hunter (1985) considered

294

AAP Memoir 42 (2011)

Figure 5. A-J, Costiconus ethingtoni (Fåhraeus, 1966). A, ?M element, CNP1218, CN578, posterior view (IY174-012). B-D, Sb element, CNP1219, CN487, B, outer lateral view (IY179-005), C, basal view (IY179004), D, inner lateral view (IY179-004). E, Sd element, CNP1220, CN555, posterior view (IY177-019). F, Sb element, CNP1221, CN343, inner lateral view (IY181-025). G-H, Sc element; G, CNP1222, CN555, outer lateral view (IY177-016); H, CNP1223, CN578, inner lateral view (IY174-013). I, Pa element, CNP1224, CN555, inner lateral view (IY177-020). J, Pb element, CNP1225, CN578, inner lateral view (IY174-011). K-L, Erraticodon? sp. M element, CNP1226, CN493, K, posterior view (IY183-012), L, close up showing fine surface striation (IY183-013). M, Baltoniodus sp. Pa element, CNP1227, CN343, outer lateral view (IY181012). scale bars 100 μm, unless otherwise indicated.

A. jemtlandica to consist of a quinquimembrate apparatus. Based on a large collection of well preserved specimens from allochthonous limestone blocks in the Oakdale Formation of central New South Wales, it was subsequently interpreted as consisting of a seximembrate apparatus (Zhen & Percival 2004a). In the Maruia samples, A. jemtlandica is moderately common with all six element types recognised (Fig. 4AP), which are identical with those previously

documented from central New South Wales (Zhen & Percival 2004a). Aurilobodus Xiang & Zhang in An et al., 1983 Type species. Tricladiodus? aurilobus Lee, 1975. Aurilobodus sp. (Fig. 8M-N) Material. Two specimens recovered from one

295

AAP Memoir 42 (2011) sample (CN482, see Table 1). Remarks. Xiang & Zhang (in An et al. 1983, p. 71-72) defined Aurilobodus as consisting of a bimembrate (symmetrical and asymmetrical) apparatus, and originally assigned to it five species and two informal species from the Majiagou (Machiakou) Formation (spanning the variabilis-suecicus zones of the Darriwilian) of Shandong and Hebei provinces in North China. Specimens referable to this genus have also been reported from the same stratigraphic level in Korea (Lee 1975), Australia (Watson 1988) and southeast Asia (Agematsu et al. 2006, 2008a, 2008b). Only two specimens were recovered from the Maruia samples, and these are postulated to represent the symmetrical and asymmetrical elements of a single species of Aurilobodus (Fig. 8M-N). The symmetrical element (Fig. 8M) is comparable with that of A. simplex Xiang & Zhang (in An et al. 1983, pl. 22, figs 9, 11). The asymmetrical element (Fig. 8R), which can be easily differentiated from any species previous assigned to Aurilobodus, has a stout cusp with a broad and widely swollen posterior face and with the blade-like costa only developed on one side. Costiconus Rasmussen, 2001 Type species. Panderodus ethingtoni Fåhraeus, 1966. Costiconus ethingtoni (Fåhraeus, 1966) (Fig. 5A-J) 1966 Panderodus ethingtoni; Fåhraeus, p. 26, pl. 3, fig. 5a-b. 1974 Walliserodus ethingtoni (Fåhraeus); Bergström et al., pl. 1, fig. 12. 1978 Walliserodus ethingtoni (Fåhraeus); Löfgren, p. 114-116, pl. 4, figs 27-35, text-fig. 33 (cum syn.). 1985 Walliserodus ethingtoni (Fåhraeus); Fåhraeus & Hunter, p. 1180, pl. 3, figs 11-16, text-fig. 6. 1987 Walliserodus ethingtoni (Fåhraeus); An, p. 195-196, pl. 8, figs 28-31, pl. 12, fig. 22. 1998a Walliserodus ethingtoni (Fåhraeus); Zhang, p. 95-96, pl. 18, figs 10, 12-15, ?11 (cum syn.). 1998 Walliserodus ethingtoni (Fåhraeus); Albanesi et al., p. 115, pl. 14, figs 20-25, text-fig. 8. 2000 Walliserodus ethingtoni (Fåhraeus); Zhao et al., p. 230, pl. 22, figs 1-6. 2001 Costiconus ethingtoni (Fåhraeus); Rasmussen, p. 62-64, pl. 3, figs 16-18 (cum syn.). 2008 Costiconus ethingtoni (Fåhraeus); Ortega

et al., fig. 6.22. 2009a Costiconus ethingtoni (Fåhraeus); Zhen et al., p. 139-140, fig. 3A-W, ?R-T. 2009b Costiconus ethingtoni (Fåhraeus); Zhen et al., p. 31-33, fig. 4H-W. 2011 Costiconus ethingtoni (Fåhraeus); Viira, fig. 7O, Q. 2011 Costiconus ethingtoni (Fåhraeus); Zhen et al., p. 221, figs 6A-L, 7A-U (cum syn.). Material. 55 specimens recovered from 12 samples (see Table 1). Remarks. Costiconus ethingtoni was considered by Zhen et al. (2011) to consist of a coniform septimembrate apparatus including shortbased, non-geniculate M element (Fig. 5A), multicostate, symmetrical Sa element, multicostate asymmetrical Sb element (Fig. 5B-D, F), multicostate, asymmetrical and strongly laterally compressed Sc element (Fig. 5G-H), pentacostate symmetrical Sd element (fig. 5E), non-costate Pa element with a proclined cusp (Fig. 5I), and non-costate Pb element with a suberect cusp (Fig. 5J). All except the symmetrical Sa element have been recognised in the Maruia material (Fig. 5A-J). Zhen et al. (2009a) illustrated a unicostate specimen with a suberect cusp and a short base as representing the Pb element. More recently this was reassigned to the M element (Zhen et al. 2011). However, among the large number of specimens of this species examined from the Tarim Basin (Zhen et al. 2011) and from the Maruia samples, no unicostate specimens have been recognised, although its elements show wide variation. Therefore, inclusion of this specimen (Zhen et al. 2009a, fig. 3R-T) in the species may be doubtful. Drepanodus Pander, 1856 Type species. Drepanodus arcuatus Pander, 1856. Drepanodus reclinatus (Lindström, 1955) (Fig. 6A-K) 1955 Acontiodus reclinatus; Lindström, p. 548, text-fig. 3C, pl. 2, figs 5-6. 2003 Drepanodus reclinatus (Lindström); Löfgren & Tolmacheva, p. 216-217, figs 5A-J, 7A-G (cum syn.). 2007 Drepanodus reclinatus (Lindström); Ortega et al., fig. 6M. 2008 Drepanodus reclinatus (Lindström); Ortega et al., fig. 6.17-6.18. 2011 Drepanodus reclinatus (Lindström); Zhen et al., p. 222, fig. 11A-P (cum syn.).

296

AAP Memoir 42 (2011)

Figure 6. A-K, Drepanodus reclinatus (Lindström, 1955). A, ?M element, CNP1228, CN487, posterior view (IY179-002). B, Sa element, CNP1229, CN507, lateral view (IY183-021). C, ?Sb element, CNP1230, CN487, outer lateral view (IY178-013); D, Sb element, CNP1231, CN579, inner lateral view (IY175-022). E, J-K, Pb element; E, CNP1236, CN487, outer lateral view (IY179-007); J, CNP1237, CN579, inner lateral view (IY175-018); K, CNP1238, CN579, outer lateral view (IY175-019). F-G, Sc element; F, CNP1232, CN579, outer lateral view (IY176-002); G, CNP1233, CN579, inner lateral view (IY176-001). H-I, Pa element; H, CNP1234, CN463, outer lateral view (IY183-027); I, CNP1235, CN579, outer lateral view (IY175-017). L-N, Drepanoistodus sp. L, Sb element, CNP1239, CN482, outer lateral view (IY183-015). M-N, Sc element; M, CNP1240, CN507, outer lateral view (IY183-020); N, CNP1241, CN497, inner lateral view (IY183-014). Scale bars 100 μm.

Material. 304 specimens recovered from 20 samples (see Table 1). Remarks. Drepanodus reclinatus is one of the dominant species in the Maruia fauna and its

specimens are often much larger than other associated species in the samples. It differs from the type species, D. arcuatus, in having costate elements, typically with one or two posterolateral costa in the S and P elements (Fig. 6B-K). Löfgren

297

AAP Memoir 42 (2011) & Tolmacheva (2003, p. 216, figs 5J, 7A) defined the M element as having a costa on the anterior face (located towards the outer lateral margin) and a carina on the posterior face. However, in the current collection, the only specimen illustrated as a doubtful M element (Fig. 6A) exhibits a less outer-laterally expanded base with a smooth anterior face and a prominent costa on the posterior face. The Pb element has a sharp costa located near the posterior margin on the outer lateral face (Fig. 6K) and a nearly smooth inner lateral face (Fig. 6J), occasionally with a weak carina as defined by Löfgren & Tolmacheva (2003). The Sd element of D. reclinatus defined by Löfgren & Tolmacheva (2003, p. 217) was not recognised among the current material. Based on the description given by these authors, the Sd element is closely similar to the Sb element, except that the anterior edge of the base is flexed inward and the costae on both sides are more or less equally developed. Specimens referred to Drepanoistodus sp. (Fig. 6L-N) resemble D. reclinatus in having a costa on one or both sides of the element, but display a more flared base that is comparable to other species of Drepanoistodus. The diagnostic symmetrical Sa element of Drepanoistodus was not recovered from the Maruia samples.

7G, J) elements are recognised. Zhang (1998a) revised D. tablepointensis as consisting of a seximembrate apparatus, including stelliscaphate Pa and Pb, geniculate M and ramiform S (with Sa, Sb and Sd recognised) elements. However, a septimembrate species apparatus can be postulated by including a modified bipennate ramiform element similar to that illustrated by Löfgren (1990, fig. 1e) to take the Sc position. Zhen & Percival (2004b, fig. 7Q) illustrated a specimen that they assigned to the Sc position of Dzikodus hunanensis Zhang, 1998a, but this is a modified quadriramate element and more likely represents a variant of the Sd element of that species. Eoplacognathus Hamar, 1966 Type species. Ambalodus lindstroemi Hamar, 1966. Eoplacognathus suecicus Bergström, 1971a (Fig. 7A-E)

1984 Polonodus? tablepointensis; Stouge, p. 72, pl. 12, fig. 13, pl. 13, figs 1-5. 1998a Dzikodus tablepointensis (Stouge); Zhang, pp. 65-69, pl. 7, figs 1-12, pl. 8, figs 1-6 (cum syn.). 1999 Polonodus tablepointensis Stouge; Ottone et al., p. 242, pl. 6, fig. 9. 2007 Dzikodus tablepointensis (Stouge); Ortega et al., fig. 5Q.

1971a Eoplacognathus suecicus; Bergström, p. 141, pl. 1, figs 5-7. 1977 Eoplacognathus suecicus Bergström; L i n d s t r ö m i n Z i e g l e r, p . 1 4 3 - 1 4 4 , Eoplacognathus-plate 2, figs 7-9. 1979 Eoplacognathus suecicus Bergström; Harris et al., pl. 2, figs 8-10. 1990 Eoplacognathus suecicus Bergström; An & Zheng, partim, only pl. 14, fig. 14. 1998a Eoplacognathus suecicus Bergström; Zhang, pp. 70-71, pl. 8, figs 11-13. 1998 Eoplacognathus suecicus Bergström; Zhang & Sturkell, fig. 7I-L. 1999 Eoplacognathus suecicus Bergström; Zhang, pp. 487-493, figs 2.5-2.25, 3.1-3.24, fig. 4.3-4.6 (cum syn.). 2001 Eoplacognathus suecicus Bergström; Viira et al., fig. 8m-p. ?2003 Eoplacognathus suecicus Bergström; Pyle & Barnes, fig. 15.3. ?2011 Eoplacognathus suecicus Bergström; Viira, fig. 5J-M.

Material. 20 specimens recovered from five samples (see Table 1).

Material. Five specimens recovered from three samples (see Table 1).

Remarks. Zhang (1998a) established Dzikodus as characterised by paired similar Pa elements and unpaired, markedly dissimilar Pb elements, distinguishing this genus from Polonodus that has both paired Pa and Pb elements. Most of the specimens referable to this species in the Mauria samples are poorly preserved, and only M (Fig. 7K), Sb (Fig. 7H, L), Pa (Fig. 7I), and Pb (Fig.

Remarks. Eoplacognathus suecicus was erected as having four types of platform elements, including unpaired sinistral and dextral Pa (stelliplanate) and Pb (pastiniplanate) elements (Bergström 1971a, p. 141). However, as Zhang (1999) pointed out, since the holotype was a juvenile specimen representing the dextral Pb element (Bergström 1971a, pl. 1, fig. 6) and the

Dzikodus Zhang, 1998a Type species. Polonodus tablepointensis Stouge, 1984. Dzikodus tablepointensis (Stouge, 1984) (Fig. 7G-L)

298

AAP Memoir 42 (2011)

Figure 7. A-E, Eoplacognathus suecicus Bergström, 1971a. A-E, dextral Pa (stelliplanate) element; A-B, CNP1242, CN578, A, upper view (IY174-001); B, upper view, close up showing surface reticulation (IY174002); C, CNP1243, CN578, upper view (IY174-009); D, CNP1244, CN579, upper view (IY175-009); E, CNP1245, CN487, upper view (IY177-033). F, Yangtzeplacognathus foliaceus (Fåhraeus, 1966). dextral Pb (pastiniplanate) element, CNP1246, CN579, upper view (IY175-008). G-L, Dzikodus tablepointensis (Stouge, 1984). G, J, Pb element; G, CNP1247, CN463, upper view (IY180-025); J, CNP1248, CN495, upper view (IY179-009). I, Pa element, CNP1249, CN495, upper view (IY179-008). H, L, Sb element; H, CNP1250, CN495, postero-inner lateral view (IY179-017); L, CNP1251, CN495, inner lateral view (IY179-015). K, M element, CNP1252, CN495, posterior view (IY179-016). M, Polonodus sp. Pa element, CNP1253, CN482, upper view (IY182-012). Scale bars 100 μm, unless otherwise indicated.

AAP Memoir 42 (2011)

299

Figure 8. A-J, Erraticodon? sp. A, Sd element, CNP1254, CN463, upper lateral view (IY185-015). B, M element, CNP1255, CN463, posterior view (IY185-017). C, Sc element, CNP1256, CN558c, inner lateral view (IY185-007). D, Sb element, CNP1257, CN558a, inner lateral view (IY180-010). E-G, Pa element; E, CNP1258, CN463, posterior view (IY180-031); F, CNP1259, CN463, posterior view of two fused specimens (IY180-027); G, CNP1260, CN463, posterior view (IY180-030). H-J, Pb element; H-I, CNP1261, CN555, posterior view (IY177-004) and upper view (IY177-006); J, CNP1262, CN558a, anterior view (IY180007). K-L, Pygodus? sp. Pa element, CNP1263, CN343, inner lateral views (IY181-015, IY181-016). M-N, Aurilobodus sp. M, symmetrical element, CNP1268, CN482, posterior view (IY183-018). N, asymmetrical element, CNP1269, CN482, posterior view (IY183-019). Scale bars 100 μm.

300

dextral Pa element was not defined originally, this stratigraphically important index species was interpreted rather differently by subsequent authors, and distinguishing between E. seucicus and several closely related species became rather difficult. In her revision and detailed description of this species based on a large collection (over 600 specimens) from Sweden, Zhang (1999) suggested that the Pa elements, which were represented as near mirror-image pairs, were more diagnostic in recognising this species, in particular showing a prominent expansion (often with one or more denticles developed, see Fig. 7A-B) on the outer side of the often curved posterior process and also bearing a secondary posterolateral process (Fig. 7E). The only previous record of E. suecicus in Australasia is from the Canning Basin of Western Australia (Watson 1988, p. 112, pl. 6, figs 28, 32-33, pl. 7, figs 3, 5). However, Zhang (1999, p. 492) suggested that those specimens more likely belonged to E. pseudoplanus (Viira) as the stelliplanate Pa element illustrated by Watson (1988, pl. 6, fig. 32, pl. 7, fig. 5) did not exhibit a secondary denticle row on the posterolateral process. In the material from the Maruia district, E. suecicus is relatively rare, and only several specimens (Table 1) representing the dextral Pa element were recovered (Fig. 7A-E). They are identical with some of the specimens illustrated by Zhang (1999, fig. 3.1, 3.8, 3.14, 3.20) from the Pygodus anitae Subzone of Jämtland, Sweden, but only one specimen (Fig. 7E) shows the well developed secondary denticle row on the posterolateral process. Erraticodon Dzik, 1978

AAP Memoir 42 (2011) New South Wales (Zhen & Percival 2004b). Histiodella Harris, 1962 Type species. Bryantodina sinuosa Graves & Ellison, 1941. Histiodella kristinae Stouge, 1984 (Fig. 9A-B) 1981 Histiodella intertexa; An in An et al., pl. 1, fig. 20; nomen nudum. 1984 Histiodella holodentata Ethington & Clark; Nowlan & Thurlow, pl. 1, figs 1, 3, 5. 1984 Histiodella kristinae; Stouge, p. 87, pl. 18, figs 1-7, 9-11, fig. 17 (cum syn.). 1994 Histiodella kristinae Stouge; Dzik, p. 110, pl. 24, figs 28-30, text-fig. 30. 1998a Histiodella kristinae Stouge; Zhang, p. 72, 73, pl. 9, figs 16, 17 (cum syn.). 2000 Histiodella kristinae Stouge; Zhao et al., p. 206, pl. 27, fig. 11. 2001 Histiodella kristinae Stouge; Rasmussen, p. 84, pl. 8, figs 1-3, 5. 2005 Histiodella kristinae Stouge; Du et al., p. 265, pl. 1, figs 6-21. 2011 Histiodella kristinae Stouge; Viira, fig. 9N, O. 2011 Histiodella kristinae Stouge; Zhen et al., p. 229, fig. 14C-F (cum syn.). Material. Two specimens recovered from samples CN558a and CN463 (see Table 1). Remarks. Histiodella kristinae is only sparingly represented in the current collection by specimens of the Pa element (Fig. 9A-B) that are identical with some of the paratypes illustrated by Stouge (1984, pl. 18, figs 6-7) from the Table Head Formation of western Newfoundland.

Type species. Erraticodon balticus Dzik, 1978. Paroistodus Lindström, 1971 Erraticodon? sp. (Figs 5K-L, 8A-J) Type species. Oistodus parallelus Pander, 1856. Material. 38 specimens recovered from nine samples (see Table 1). Remarks. The illustrated M element (Figs 5K-L, 8B) is comparable with that of the type species, E. balticus. However the S elements, although poorly preserved, are readily differentiated from the corresponding elements of E. balticus in lacking an excessively enlarged denticle on the posterior process. Erraticodon balticus was recently revised as consisting of a septimembrate species apparatus, based on a large collection from Kirkup Station, near Parkes, central New South Wales (Zhen & Pickett 2008, p. 67-72) and was also reported from the Weemalla Formation of

Paroistodus horridus (Barnes & Poplawski, 1973) (Fig. 9G-O) 1973 Cordylodus horridus; Barnes & Poplawski, p. 771-772, pl. 2, figs 16-18. 1995 Paroistodus horridus (Barnes & Poplawski); Lehnert, p. 108, pl. 9, figs 15-16, pl. 11, figs 2, 12, pl. 13, fig. 7. 1999 Paroistodus horridus (Barnes & Poplawski); Ottone et al., p. 240, text-fig. 3.4-3.7. 2000 Paroistodus horridus (Barnes & Poplawski); Albanesi & Barnes, figs 3.1, 5.1, 5.2, 5.8-5.12. 2004a Paroistodus horridus (Barnes & Poplawski); Zhen & Percival, pp. 98-101, fig.

AAP Memoir 42 (2011)

301

Figure 9. A-B, Histiodella kristinae Stouge, 1984. Pa element; A, CNP1270, CN558a, outer lateral view (IY180-001); B, CNP1271, CN463, outer lateral view (IY180-024). C-E, Panderodus gracilis (Branson & Mehl, 1933). C, graciliform element, CNP1272, CN555, inner lateral view (IY177-024). D-E, falciform element; D, CNP1273, CN555, inner lateral view (IY177-021); E, CNP1274, CN482, outer lateral view (IY183-016). F, Gen. et sp. indet. Sc element, CNP1275, CN558a, outer lateral view (IY180-014). G-O, Paroistodus horridus (Barnes & Poplawski, 1973). G-H, M element; G, CNP1276, CN558c, posterior view (IY179-019); H, CNP1277, CN558a, anterior view (IY180-002). I, Sa element, CNP1278, CN558c, lateral view (IY179023). J-K, Sb element; J, CNP1279, CN558c, inner lateral view (IY179-023); K, CNP1280, CN558c, outer lateral view (IY179024). L, Sc element, CNP1281, CN558c, inner lateral view (IY179-025). M, Pb element, CNP1282, CN482, inner lateral view (IY182-013). N-O, Sc element; N, CNP1283, CN558a, inner lateral view (IY180-011); O, CNP1284, CN558a, inner lateral view (IY180-008). Scale bars 100 μm, unless otherwise indicated.

15A-L (cum syn.). 2007 Paroistodus horridus (Barnes & Poplawski); Percival & Zhen, pl. 1, fig. 24-26. 2007 Paroistodus horridus (Barnes & Poplawski); Ortega et al., fig. 6R-S. 2009b Paroistodus horridus (Barnes & Poplawski); Zhen et al., p. 43, fig. 11A-B.

Material. 98 specimens recovered from eight samples (see Table 1). Remarks. Paroistodus horridus was revised as consisting of a seximembrate species apparatus (Zhen & Percival 2004a). It is relatively common in the Maruia material, although the majority of the recovered specimens are poorly preserved;

302

AAP Memoir 42 (2011)

Figure 10. Periodon macrodentatus (Graves & Ellison, 1941). A-B, M element; A, CNP1285, CN580, posterior view (IY176-012); B, CNP1286, CN578, anterior view (IY174-025). C-D, Sa element, CNP1287, CN580, lateral views (IY176-015, IY176-016). E-G, Sb element; E, CNP1288, CN578, outer lateral view (IY174-028); F, CNP1289, CN555, inner lateral view (IY177-013); G, CNP1290, CN555, inner lateral view (IY177-014). H, Sc element, CNP1291, CN555, outer lateral view (IY177-015). I-J, Pa element; I, CNP1292, CN578, inner lateral view (IY174-023); J, CNP1293, CN578, outer lateral view (IY174-024). K, Pb element, CNP1294, CN580, inner lateral view (IY176-017). Scale bars 100 μm.

specimens representing the M (Fig. 9G-H), Sa (Fig. 9I), Sb (Fig. 9J-K), Sc (Fig. 9L, N-O), and Pb (Fig. 9M) elements were recognised. Periodon Hadding, 1913 Type species. Periodon aculeatus Hadding, 1913. Periodon macrodentatus (Graves & Ellison, 1941) (Fig. 10A-K) 1941 Ozarkodina macrodentata; Graves & Ellison, p. 14, pl. 2, figs 33, 35, 36. 1976 Periodon macrodentata (Graves & Ellison); Cawood, fig. 3a. 2001 Periodon macrodentata (Graves & Ellison); Rasmussen, p. 114-116, pl. 14, figs 1-8 (cum

syn.). 2004b Periodon macrodentatus (Graves & Ellison); Zhen & Percival, p. 168-170, fig. 10A-N (cum syn.). 2007 Periodon macrodentatus (Graves & Ellison); Percival & Zhen, p. 392, pl. 1, figs 32-33. 2008 Periodon macrodentatus (Graves & Ellison); Ortega et al., fig. 6.12. 2009b Periodon macrodentatus (Graves & Ellison); Zhen et al., p. 45-47, fig. 9A-T. Material. 464 specimens recovered from 20 samples (see Table 1). Remarks. As in the faunas recently documented from Thompson Creek of New Zealand (Zhen

AAP Memoir 42 (2011)

303

Figure 11. A-C, Polonodus clivosus (Viira, 1974). A, dextral Pa (polyplacognathiform) element, CNP1295, CN323, upper view (IY181-002); B, sinistral Pa (polyplacognathiform) element, CNP1296, CN323, upper view (IY181-003). C, dextral Pb (ambalodontiform) element, CNP1297, CN323, upper view (IY181-006). D-H, Polonodus newfoundlandensis Stouge, 1984. D, sinistral Pa (polyplacognathiform) element, CNP1298, CN343, upper view (IY181-013). E, dextral Pb (ambalodontiform) element, CNP1299, CN343, upper view (IY181-017). F-H, Sd element, CNP1300, CN343, F, inner lateral view (IY181-020), G, anterior view (IY181021), H, upper view (IY181-019). I-L, Polonodus sp. I, sinistral Pa (polyplacognathiform) element, CNP1301, CN596a, upper view (IY183-025). J, Pb (ambalodontiform) element, CNP1302, CN596a, upper view (IY181031). K, Sb element, CNP1303, CN479, outer lateral view (IY182-008). L, Sd element, CNP1304, CN479, inner lateral view (IY182-007). M-O, Prioniodus sp. M-N, Pa element; M, CNP1305, CN555, basal view (IY177-009); N, CNP1306, CN555, outer lateral view (IY177-008). O, Sd element, CNP1307, CN555, basal outer lateral view (IY177-011). Scale bars 100 μm.

et al. 2009b) and from the Weemalla Formation of central New South Wales (Zhen & Percival 2004b), P. macrodentatus is the most dominant species in the fauna from the Maruia district.

Specimens from all three areas are identical, notwithstanding the relatively poor preservation of those in the current collection.

304

AAP Memoir 42 (2011)

Figure 12. A-E, Protopanderodus cooperi (Sweet & Bergström, 1962). A-C, Sa element; A, CNP1308, CN487, lateral view (IY178-024); B-C, CNP1309, CN343, B, lateral view (IY181-023), C, posterior view (IY181-022). D-E, Pb element; D, CNP1310, CN479, inner lateral view (IY182-009). E, CNP1311, CN578, outer lateral view (IY174-020). F-I, Protopanderodus? nogamii (Lee, 1975). Sa element; CNP1312, CN558c, F, H, lateral views (IY179-029, IY179-028); G, posterior view of the basal part (IY179-026); I, detail of surface striation (IY179-027). J-P, Protopanderodus varicostatus (Sweet & Bergström, 1962). J, M2 element, CNP1313, CN579, posterior view (IY175-013). K, M1 element, CNP1314, CN558a, posterior view (IY180015). L, Sa element, CNP1315, CN558c, lateral view (IY175-014). M, Sb element, CNP1316, CN579, inner lateral view (IY175-016). N, Sc element, CNP1317, CN579, inner lateral view (IY175-015). O-P, Sd element; O, CNP1318, CN487, outer lateral view (IY178-011); P, CNP1319, CN487, inner lateral view (IY178-012). Scale bars 100 μm, unless otherwise indicated.

305

AAP Memoir 42 (2011) Polonodus Dzik, 1976 Type species. Ambalodus clivosus Viira, 1974.

et al., p. 233-236, fig. 17A-K. Material. 14 specimens recovered from samples CN495 and CN343 (see Table 1).

Polonodus clivosus (Viira, 1974) (Fig. 11A-C) 1967 Ambalodus n. sp.; Viira, p. 323, fig. 3.24a-b. 1970 Polyplacognathus n. sp. A; Fåhraeus, fig. 3F-G. 1970 Ambalodus n. sp. A; Fåhraeus, fig. 3J-K. 1974 Ambalodus clivosus; Viira, p. 51-52, 134, pl. 8, fig. 1, text-figs 37-38. 1974 Ambalodus? n. sp.; Viira, p. 52, pl. 8, figs 2-3, text-fig. 39. 1978 Polonodus clivosus (Viira); Löfgren, p. 76, partim, only pl. 16, figs 12-13. 1984 Polonodus clivosus (Viira); Stouge, p. 73, pl. 13, figs 6-13. 1993 Polonodus clivosus (Viira); Ding et al. in Wang, p. 191, pl. 32, figs 16, ?17. 1993 Polonodus sp. H; Ding et al. in Wang, partim only pl. 37 fig. 5. 2011 Polonodus clivosus (Viira); Zhen et al., p. 233, fig. 17L-M.

Remarks. Previous documentation and identification of this species were mainly based on the pectiniform P elements (Stouge 1984; Zhen et al. 2011), although Löfgren (1990) indicated that Polonodus species also included ramiform S and geniculate M elements in their species apparatuses. The Pa (Fig. 11D) and Pb (Fig. 11E) elements of this species from the Maruia district (sample CN343) are identical with the type material from the Table Head Formation of western Newfoundland (Stouge 1984), and those recently documented from the Dawangou Formation of the Tarim Basin (Zhen et al. 2011). A quadriramate ramiform element from the same sample illustrated herein is interpreted to represent the Sd position (Fig. 11F-H). Protopanderodus Lindström, 1971 Type species. Acontiodus rectus Lindström, 1955.

Material. 11 specimens recovered from sample CN323 (see Table 1). Remarks. Specimens referable to Polonodus are fairly common in the Maruia samples (see Table 1), but most of the recovered P elements are broken or deformed. Several better preserved specimens representing the Pa element (Fig. 11AB) lack a prominent notch between the anterior process and the secondary inner lateral process, which is the characteristic feature of P. clivosus (Stouge 1984; Zhen et al. 2011). Specimens which display this prominent notch are ascribed to P. newfoundlandensis (Fig. 11D). Poorly preserved P elements from several samples that cannot be confidently assigned to either species, and their associated ramiform specimens (Table 1), are assigned herein to Polonodus sp. (Figs 7M, 11I-L). Polonodus newfoundlandensis Stouge, 1984 (Fig. 11D-H) 1984 Polonodus newfoundlandensis; Stouge, p. 73-74, pl. 13, figs 14-16, text-fig. 28. ?1991 Polonodus sp.; Gao, partim only pl. 9, figs 8-9, ?13. 1993 Polonodus kunshanensis; Ding in Wang, p. 191, partim, only pl. 33, fig. 17, non figs 15, 18 = ?Dzikodus tablepointensis. 2000 Polonodus cf. newfoundlandensis Stouge; Zhao et al., p. 215, pl. 30, figs 16-17. 2011 Polonodus newfoundlandensis Stouge; Zhen

Protopanderodus cooperi (Sweet & Bergström, 1962) (Fig. 12A-E) 1962 Acontiodus cooperi; Sweet & Bergström, p. 1221, pl. 168, figs 2, 3, text-fig. 1G. 1983 Acontiodus cooperi Sweet & Bergström; Burrett et al., p. 180, fig. 9E. 1998a Protopanderodus cooperi (Sweet & Bergström); Zhang, p. 81, 82, pl. 14, figs 1317 (cum syn.). 2004 Protopanderodus cooperi (Sweet & Bergström); Zhen et al., p. 155, fig. 8A-E. 2004b Protopanderodus cooperi (Sweet & Bergström); Zhen & Percival, p. 170, fig. 11C-F (cum syn.). 2006 Protopanderodus robustus (Hadding); Mellgren & Eriksson, p. 106-108, figs 9H-N, 13A-K. 2009a Protopanderodus cooperi (Sweet & Bergström); Zhen et al., p. 148-150, fig. 7A-R, ?S (cum syn.). 2009b Protopanderodus cooperi (Sweet & Bergström); Zhen et al., p. 47, fig. 10S. 2011 Protopanderodus cooperi (Sweet & Bergström); Zhen et al., p. 237-239, figs 19AR, 20A-E (cum syn.). Material. 20 specimens recovered from eight samples (see Table 1). Remarks. Protopanderodus cooperi is a well documented species consisting of a septimembrate

306

apparatus with the S and P elements characterised by having a heel-like antero-basal extension, and a costa on each lateral face (Zhen et al. 2009a, 2011). The species is relatively rare in the Maruia material, and only symmetrical Sa (Fig. 12A-C) and short-based Pb (Fig. 12D-E) elements were distinguished. Protopanderodus varicostatus (Sweet & Bergström, 1962) (Fig. 12J-P) 1962 Scolopodus varicostatus; Sweet & Bergström, p. 1247, pl. 168, figs 4-9, text-fig. 1A, C, K. 1962 Scandodus unistriatus; Sweet & Bergström, p. 1245, pl. 168, fig. 12, text-fig. 1E. 1976 Protopanderodus varicostatus (Sweet & Bergström); Dzik, only text-fig. 16f, g. 1983 Protopanderodus varicostatus (Sweet & Bergström); Burrett et al., p. 184, fig. 9C, D. 1985 Protopanderodus varicostatus (Sweet & Bergström); Fåhræus & Hunter, p. 183, textfig. 2. 1998b Protopanderodus varicostatus (Sweet & Bergström); Zhang, p. 83, 84, pl. 15, figs 1419 (cum syn.). 2004b Protopanderodus varicostatus (Sweet & Bergström); Zhen & Percival, pp. 172-175, fig. 12A-M (cum syn.). 2008 Protopanderodus varicostatus (Sweet & Bergström); Ortega et al., fig. 6-20-6.21. 2009a Protopanderodus varicostatus (Sweet & Bergström); Zhen et al., p. 151, fig. 8B-I. 2011 Protopanderodus varicostatus (Sweet & Bergström); Zhen et al., p. 245-247, figs 20FL, 22A-R (cum syn.). Material. 42 specimens recovered from 13 samples (see Table 1). Remarks. Protopanderodus varicostatus was recently revised, based on topotype material from the Pratt Ferry Formation of Alabama (Zhen et al. 2011), as a multicostate Protopanderodus species consisting of a septimembrate apparatus. It can be differentiated from P. calceatus Bagnoli & Stouge, 1996 in having multicostate S and P elements that are characterised by having a strongly curved basal margin with a distinctive indentation (Fig. 12L-M) near the antero-basal corner and often with an anticusp-like extension (Fig. 12L-P) similar to that of P. cooperi. Only scandodiform M (Fig. 12J-K), symmetrical Sa (Fig. 12L), asymmetrical Sb (Fig. 12M), strongly asymmetrical Sc (Fig. 12N) and nearly symmetrical Sd (having a distinctive triangular antero-basal corner, see Fig. 12O-P) elements of this species were recovered from the Maruia

AAP Memoir 42 (2011) samples. They are closely comparable with the types (Sweet & Bergström 1962) and topotype material of P. varicostatus from North America (Zhen et al. 2011). Protopanderodus sp. (Fig. 13A-T) 2004b Protopanderodus sp.; Zhen & Percival, p. 175, fig. 12N-S. Material. 29 specimens recovered from five samples (see Table 1). Description. A species of Protopanderodus with an apparatus including long-based Sa, Sb, Sc and Sd elements that form a symmetry transition series, and short-based Pa and Pb elements; all elements multicostate. A possible scandodiform M element has yet to be recognised. Sa element symmetrical, bearing a suberect to reclined cusp and a long base; cusp arrow-like in cross section with sharp anterior and posterior margins, and with each lateral face bearing one or two posterolateral costae that extend to the tip of the cusp and often with several additional shorter costae confined to the base; base weakly expanded (Fig. 13A-C). Sb element like Sa, but asymmetrical (Fig. 13DH); cusp bearing a sharp anterior margin and a broad posterior face with a sharp costa along the posterior margin and with several posterolateral costae on posterolateral faces; inner lateral face with three or four posterolateral costae, outer lateral face more convex with four or more long posterolateral costae (Fig. 13F-H), and often with several additional shorter costae confined to the base (Fig. 13H). Sc element asymmetrical, laterally strongly compressed, with a reclined cusp and an expanded base (Fig. 13I-L); cusp with sharp anterior and posterior margins, and with 2-3 posterolateral costae on each lateral face; costae more strongly developed on the outer lateral face (Fig. 13J, L). Sd element like Sb, but less laterally compressed with a slightly twisted cusp and a broader posterior face formed by the costate posterior margin and the multicostate posterolateral portion of each lateral face (Fig. 13M-N); each lateral face bearing three or more sharp posterolateral costae; outer lateral face more convex. Pa element asymmetrical with a strongly reclined cusp and a short, moderately expanded base (Fig. 13O-Q); cusp laterally compressed with sharp anterior and posterior margins; inner lateral face flat or weakly convex with a sharp posterolateral costa that extends to the tip of the cusp and often one or more shorter costa (Fig. 13Q); outer lateral face more convex with three or more posterolateral costae (Fig. 13O-P). Pb element bearing a suberect cusp and a short base

AAP Memoir 42 (2011)

307

Figure 13. Protopanderodus sp. A-C, Sa element; A, CNP1320, CN579, lateral view (IY175-021); B-C, CNP1321, CN487, lateral views (IY184-003, IY178-015). D-H, Sb element; D-F, CNP1322, CN487, D, basal view (IY184-010), E, inner lateral view (IY184-011), F, outer lateral view (IY178-026); G-H, CNP1323, CN558c, G, upper posterior view (IY179-031), H, outer lateral view (IY179-030). I-L, Sc element; I-J, CNP1324, CN487, I, inner lateral view (IY178-014), J, outer lateral view (IY184-002). K-L, CNP1325, CN487, K, inner lateral view (IY184-012), L, outer lateral view (IY178-028). M-N, Sd element, CNP1326, CN487, M, inner posterior view (IY178-021), N, outer lateral view (IY184-007). O-Q, Pa element; O, CNP1327, CN487, outer lateral view (IY178-018); P-Q, CNP1328, CN487, P, outer lateral view (IY184-004), Q, inner lateral view (IY178-017). R-T, Pb element, CNP1329, CN487, R, inner lateral view and S, detail of basal part (IY178025), T, outer lateral view of basal part (IY184-008). Scale bars 100 μm.

308

with anterior and posterior portions of the basal margin nearly normal to each other (Fig. 13R-T); cusp laterally compressed with sharp anterior and posterior margins and with two costae on the inner lateral face (Fig. 13S) and one costa on the more convex outer lateral face (Fig. 13T).

AAP Memoir 42 (2011)

Type species. Pygodus anserinus Lamont & Lindström 1957.

with a wide anterior platform bearing four or five rows of nodes, and an inconspicuous, laterally compressed cusp at the apex, where rows of denticles converge (Fig. 14E-H, J). Reticulate surface structure is well developed in some of the specimens (Fig. 14I). One specimen referred herein to Pygodus? sp. represents a new form possibly related to Pygodus (Fig. 8K-L). It has a robust, laterally compressed cusp, a wide open basal cavity and a distally widening platform, which is split into anterior, central and posterior lobes. The anterior lobe is wider with two rows of node-like denticles, one row along the anterior margin and the other near the posterior margin. The central lobe has one median row of node-like denticles, and the narrower posterior lobe is distally broken with a row of laterally compressed denticles.

Pygodus anitae Bergström, 1983 (Fig. 14A-J)

Pygodus serra (Hadding, 1913) (Fig. 14K-N)

1978 Pygodus sp. C; Löfgren, p. 97, pl. 16, figs 4-6, text-fig. 32A-C. 1983 Pygodus anitae; Bergström, p. 55, fig. 6V-Z. 1990 Pygodus anitae Bergström; An & Zheng, p. 170-171, pl. 13, figs 4-6, pl. 14, fig. 18 (cum syn.). 1998 Pygodus anitae Bergström; Zhang & Sturkell, fig. 7N-S. 1998 Pygodus anitae Bergström; Albanesi et al., p. 162, pl. 15, figs 7-10. 1998c Pygodus anitae Bergström; Zhang, text-fig. 2B1, B2; text-fig. 4D, pl., 1, figs 1-4. 1999 Pygodus anitae Bergström; Ottone et al., 242, pl. 6, figs 1, 4-5. 2000 Pygodus anitae Bergström; Zhao et al., p. 220, pl. 29, figs 16-17, 19; pl. 35, fig. 15. 2001 Pygodus anitae Bergström; Pickett & Percival, fig. 4D. 2007 Pygodus anitae Bergström; Ortega et al., fig. 5R.

1913 Arabellites serra; Hadding, p. 13, pl. 1, figs 12, 13. 1971a Pygodus serrus (Hadding); Bergström, p. 149, pl. 2, figs 22, 23. 1974 Pygodus serrus (Hadding); Bergström et al., pl. 1, fig. 18. 1979 Pygodus serra (Hadding); Harris et al., pl. 2, fig. 18. 1980 Pygodus serrus (Hadding); Nicoll, fig. 3H-L. 1981 Pygodus serrus (Hadding); An, pl. 4, figs 1-3. 1990 Pygodus serra (Hadding); Bergström, pl. 1, figs 23-24. 1990 Pygodus serra (Hadding); Pohler & Orchard, pl. 1, fig. 18. 1991 Pygodus serra (Hadding); McCracken, p. 51, pl. 2, figs 4, 6-7, 9, 11-12, 14-18, 20-23, 28-30. 1994 Pygodus serra (Hadding); Dzik, p. 103-105, pl. 17, figs 9-12, text-fig. 26. 1998 Pygodus serra (Hadding); Zhang &Sturkell, fig. 7M. 1998c Pygodus serra (Hadding); Zhang, p. 96, pl. 2, figs 3-5, 8-14, text-figs 2C1, C3, 4B (doubtful pl. 2, figs 1, 2, 6, 7, text-fig. 2C2 = P. xinjiangensis) (cum syn.). 1998c Pygodus protoanserinus; Zhang, p. 96, text-fig. 2D, pl. 3, figs 9-18 (cum syn.). 1998a Pygodus protoanserinus Zhang; Zhang, p. 86-87, pl. 16, figs 6-8 (cum syn.). 1999 Pygodus serra (Hadding); Lehnert et al., pl. 2, fig. 12. 1999 Pygodus serra (Hadding); Ottone et al., p. 242, pl. 6, figs 2-3. 2001 Pygodus serra (Hadding); Pickett & Percival, fig. 4C.

Remarks. This multicostate species of Protopanderodus, characterised by posterolaterally located costae, was also recorded from the basal part of the Weemalla Formation (early Darriwilian) of central New South Wales (Zhen & Percival 2004b). Pygodus Lamont & Lindström, 1957

Material. 59 specimens recovered from four samples (see Table 1). Remarks. Pygodus anitae may consist of a seximembrate apparatus, but in the Maruia material only Pa, Pb, Sa and Sd elements (Fig. 14A-J) were recovered. The Pb, Sa and Sd elements resemble the corresponding elements of P. serra, but typically display more widely spaced and more posteriorly reclined denticles on the posterior process in the Sa and Pb elements. Both specimens illustrated herein representing the Sa (Fig. 14A) and Pb (Fig. 14D) elements also show a faintly developed ridge-like costa on the lateral side of each denticle on the posterior process. The Pa element of P. anitae is distinctive,

AAP Memoir 42 (2011)

309

Figure 14. A-J, Pygodus anitae Bergström, 1983. A, Sa element, CNP1330, CN578, lateral view (IY173-013). B, Sd element, CNP1331, CN578, outer lateral view (IY173-022). C-D, Pb element; C, CNP1332, CN574, outer lateral view (IY176-025); D, CNP1333, CN578, outer lateral view (IY173-021). E-J, Pa element; E, CNP1334, CN578, upper view (IY173-003); F, CNP1335, CN578, basal view (IY173-006); G, CNP1336, CN578, upper view (IY173-011); H-I, CNP1337, CN578, H, upper view (IY173-009), I, detail of surface reticulation pattern (IY173-010); J, CNP1338, CN574, upper view (IY176-22). K-N, Pygodus serra (Hadding, 1913). K, Pb element, CNP1339, CN553, outer lateral view (IY180-020). L-N, Pa element; L, CNP1340, CN553, upper view (IY180-018); M, CNP1341, CN487, upper view (IY177-032); N, CNP1342, CN487, upper view (IY177-029). Scale bars 100 μm, unless otherwise indicated.

2004 Pygodus protoanserinus Zhang; Zhen et al., p. 158, fig. 9B-J (cum syn.). 2007a Pygodus serra (Hadding); Bergström, fig. 4. 2007 Pygodus serra (Hadding); Percival & Zhen, pl. 1, figs 1-3, 19.

2007 Pygodus protoanserinus Zhang; Percival & Zhen, pl. 1, figs 17-18. 2011 Pygodus serra (Hadding); Zhen et al., p. 250, fig. 25A-R (cum syn.). Material. Nine specimens recovered from

310

AAP Memoir 42 (2011)

Figure 15. Spinodus spinatus (Hadding, 1913). A-B, Sb element; A, CNP1343, CN343, inner lateral view (IY181-009); B, CNP1344, CN343, upper-inner lateral view (IY181-008). C-E, Sc element; C, CNP1345, CN343, inner lateral view (IY181-010); D, CNP1346, CN507, inner lateral view (IY182-010); E, CNP1347, CN507, outer lateral view (IY182-011). F-H, Sd element, CNP1348, CN497, F, inner lateral view (IY183-011), G, basal view (IY183-010), H, outer lateral view (IY183-009). Scale bars 100 μm.

samples CN575, CN553 and CN487 (see Table 1). Remarks. Pygodus serra is a widely distributed, important zonal index species consisting of six or seven element types including M?, Sa, Sb, Sc, Sd, Pa and Pb elements (Zhang 1998a, 1998c; Zhen et al. 2004, 2011). Zhen et al. (2011) indicated that absence of the makellate M element in a large collection with both P. serra and P. anserinus, recovered from the Saergan Formation and the Kanling Formation of the Tarim Basin, favoured the interpretation that Pygodus species had a seximembrate apparatus. In the Maruia material, P. serra is rare and only the Pa and Pb elements were recognised (Fig. 14K-N). Spinodus Dzik, 1976 Type species. Polygnathus spinatus Hadding, 1913. Spinodus spinatus (Hadding, 1913) (Fig. 15A-H) 1913 Polygnathus spinatus; Hadding, p. 32, pl. 1, fig. 8.

1913 Cordylodus ramosus; Hadding, p. 31, pl. 1, fig. 6. 1976 Spinodus spinatus (Hadding); Dzik, p. 424, fig. 21c. 1991 Spinodus spinatus (Hadding); McCracken, p. 52, pl. 1, fig. 2. 1998 Spinodus spinatus (Hadding); Albanesi et al., p. 176-177, pl. 13, figs 1-7, text-fig. 32. 1998a Spinodus spinatus (Hadding); Zhang, p. 91-93, pl. 17, fig. 14 (cum syn.). 1999 Spinodus spinatus (Hadding); Ottone et al., p. 242, text-fig. 3.2. 2000 Spinodus spinatus (Hadding); Zhao et al., p. 225, pl. 36, figs 17-19. 2004b Spinodus sp. cf. spinatus (Hadding); Zhen & Percival, p. 175, fig. 13C-G (cum syn.). 2007 Spinodus spinatus (Hadding); Percival & Zhen, p. 391, pp. 1, figs 13-15. 2007 Spinodus spinatus (Hadding); Ortega et al., fig. 6W. 2007a Spinodus spinatus (Hadding); Bergström, p. 81-82. 2011 Spinodus spinatus (Hadding); Zhen et al., fig. 23O-P.

AAP Memoir 42 (2011) Material. 78 specimens recovered from 14 samples (see Table 1). Remarks. Relatively common in the Maruia samples, S. spinatus is a widely distributed species with a long stratigraphic range extending from the Early Ordovician (O. evae Zone) to Late Ordovician (A. superbus Zone). Its distribution was restricted to the shelf edge and basinal deposits (Zhang 1998a, p. 92). The apparatus of this species and its affinities are still poorly known, although elements representing a symmetry transition series (S elements) were widely reported. Albanesi (in Albanesi et al. 1998) assigned Spinodus to the Chirognathidae, and suggested a seximembrate (including ramiform Pa, Pb, M, Sa, Sb and Sc elements) species apparatus for S. spinatus, differentiating the P elements from other elements (M and S) by their having a prominent anticusp (Albanesi in Albanesi et al. 1998, pl. 13, fig. 4). However, Zhang (1998a) followed Lindström’s (1964) interpretation in considering S. spinatus as consisting of a trimembrate apparatus (Sa, Sb and Sc) forming a transition series, and suggested that the occurrence of the anti-cusp had little significance in differentiating its element types. Yangtzeplacognathus Zhang, 1998b Type species. Polyplacognathus jianyeensis An & Ding, 1982. Yangtzeplacognathus foliaceus (Fåhraeus, 1966) (Figs 7F, 16A-K, 17A-M) 1966 Ambalodus foliaceus; Fåhraeus, p. 18, pl. 4, fig. 2. 1966 Ambalodus n. sp.; Fåhraeus, p. 18, pl. 4, fig. 1a-b. 1971a Eoplacognathus foliaceus (Fåhraeus); Bergström, p. 138-139, pl. 1, figs 8-10 (cum syn.). 1974 Eoplacognathus foliaceus (Fåhraeus); Viira, p. 77-78, pl. 8, figs 10-11, text-figs 85-86. 1976 Eoplacognathus foliaceus (Fåhraeus); Dzik, p. 433, fig. 31a-f. 1977 Eoplacognathus foliaceus (Fåhraeus); Lindström in Ziegler, p. 133-134, Eoplacognathus-plate 1, figs 4-6 (cum syn.). 1978 Eoplacognathus foliaceus (Fåhraeus); Löfgren, p. 60-61, pl. 15, figs 19-21. 1983 Eoplacognathus foliaceus (Fåhraeus); Bergström, p. 43, fig. 2. 1984a Eoplacognathus foliaceus (Fåhraeus); Chen & Zhang, pl. 1, figs 1, 8, 15, pl. 2, fig. 1. 1984b Eoplacognathus foliaceus (Fåhraeus); Chen & Zhang, pl. 1, figs 26-29.

311

1998 Eoplacognathus foliaceus (Fåhraeus); Zhang & Sturkell, fig. 7E-H. 1998a Yangtzeplacognathus foliaceus (Fåhraeus); Zhang, p. 97, pl. 19, figs 9-12 (cum syn.). 1998b Yangtzeplacognathus foliaceus (Fåhraeus); Zhang, fig. 4Aa-b, fig. 5A-D, fig. 6A, fig. 11C1. 1999 Eoplacognathus foliaceus (Fåhraeus); Zhang, p. 492, fig. 4.7-4.8. 2001 Eoplacognathus foliaceus (Fåhraeus); Viira et al., fig. 8u. 2011 Yangtzeplacognathus foliaceus (Fåhraeus); Viira, fig. 5N, O. Material. 92 specimens recovered from eight samples (see Table 1). Remarks. Ambalodus foliaceus was erected as a form species with the only illustrated specimen (holotype) representing a dextral Pb (pastiniplanate) element (Fåhraeus 1966, pl. 4, fig. 2). Bergström (1971a) revised the species as a multielement species of Eoplacognathus, consisting of sinistral and dextral ambalodiform (= pastiniplanate Pb herein) elements, and unpaired sinistral and dextral polyplacognathiform (= stelliplanate Pa herein) elements, but only the sinistral and dextral Pb and dextral Pa element from the type stratum of southern central Sweden were illustrated (Bergström 1971a, pl. 1, figs 8-10). However, the revised diagnosis given by Lindström (in Ziegler 1977, p. 127-128) defined Eoplacognathus as having a trimembrate apparatus including sinistral and dextral Pb (ambalodiform) and a dextral Pa (amorphognathiform) elements, and did not recognise the sinistral Pa element in the species apparatus of E. foliaceus. Löfgren (1978, p. 60-61) indicated that in her collection from the middle Llanvirnian of Jämtland (northern Sweden), sinistral and dextral Pa elements are not equal in numbers, with only one dextral Pa element recovered in association with some 28 sinistral Pa elements. Löfgren (1978, pl. 15, fig. 19) only illustrated one Pa element, apparently representing the dextral form. The sinistral Pa element of this species is comparatively poorly illustrated and documented in the literature. The only illustrations include a drawing of a sinistral Pa element of E. foliaceus by Dzik (1976, fig. 31a) along with associated dextral Pa, sinistral and dextral Pb elements, and an incomplete sinistral Pa element (with the anterior process and the anterolateral process broken off) figured by Zhang (1998b, fig. 4Aa-b, fig. 5D). Bergström (1983, p. 43, fig. 2) defined E. foliaceus (and also other species of his E. foliaceus – E. elongatus species group) as having “four types

312

AAP Memoir 42 (2011)

Figure 16. Yangtzeplacognathus foliaceus (Fåhraeus, 1966). Pa element, A, E-F, I-J, sinistral; B-D, G-H, K, dextral; A, CNP1349, CN578, upper view (IY173-023); B-C, CNP1350, CN578, upper view (IY173-030), and detail of surface reticulation (IY173-031); D, CNP1351, CN578, upper view (IY173-033); E, CNP1352, CN579, upper view (IY175-005); F, CNP1353, CN579, upper view (IY175-007); G, CNP1354, CN497, upper view (IY182-015); H, CNP1355, CN497, upper view (IY182-016); I, CNP1356, CN497, upper view (IYi83003); J, CNP1357, CN497, upper view (IY183-001); K, CNP1358, CN497, upper view (IY182-023). Scale bars 100 μm, unless otherwise indicated.

of morphologically different platform elements that do not occur in mirror-images”. Zhang (1998b, fig. 5) initially considered E. foliaceus as the early representive of her new genus, Yangtzeplacognathus, which was characterised by having unpaired, markedly dissimilar sinistral and dextral pastiniplanate (Pb) and stelliplanate

(Pa) elements. According to Zhang, the dextral Pa element of Y. foliaceus (Zhang 1998b, fig. 5C) had wider platform ledges than those of the sinistral Pa element (Zhang 1998b, fig. 5D). Zhang (1999, p. 492) subsequently suggested that the sinistral and dextral Pa elements of E. foliaceus were markedly dissimilar, and have

AAP Memoir 42 (2011)

313

Figure 17. Yangtzeplacognathus foliaceus (Fåhraeus, 1966). Pb element, A-F, sinistral; G-M, dextral; A-B, CNP1359, CN578, upper view (IY173-027), and detail of surface reticulation (IY173-028); C, CNP1360, CN579, upper view (IY175-001); D, CNP1361, CN579, upper view (IY175-004); E, CNP1362, CN578, upper view (IY173-029); F, CNP1363, CN497, upper view (IY182-021); G, CNP1364, CN579, upper view (IY175-002); H, CNP1365, CN579, upper view (IY175-003); I, CNP1366, CN497, upper view (IY183-002); J, CNP1367, CN497, upper view (IY182-019); K-L, CNP1368, CN497, upper view (IY183-005), and outer lateral view (IY183-004); M, CNP1369, CN497, basal view (IY183-007). Scale bars 100 μm, unless otherwise indicated.

314

AAP Memoir 42 (2011)

Figure 18. Yangtzeplacognathus sp. A-D, sinistral Pa element; A-B, CNP1370, CN555, upper-anterior view (IY176-026), and upper view (IY176-027); C-D, CNP1371, CN555, upper view (IY176-030), and upper-outer lateral view (IY176-029). E-G, dextral Pb element; E, CNP1372, CN555, upper view (IY176-028); F-G, CNP1373, CN555, outer lateral view (IY176-031), and upper view (IY176-032). H-J, sinistral Pa element; CNP1374, CN497, upper view (IY185-008), upper-posterior view (IY185-010), and upper-anterior view (IY185-009). Scale bars 100 μm.

a shorter posterolateral process compared with that of the stratigraphically older E. suecicus. Zhang (1999, p. 492) also indicated that the sinistral Pb element of E. foliaceus had a much shorter posterior process forming an angle of about 180° with the lateral process (Fig. 17A-F), which showed a closer evolutionary relationship with Y. crassus (Chen & Zhang in Wang 1993). However, among the specimens referable to this species from the Maruia district, the sinistral and dextral Pa elements seem more or less equally represented in numbers, and the dextral Pa

element (Fig. 16B-D, G-H, K) does not exhibit wider platform ledges than those of the sinistral Pa element (Fig. 16A, E-F, I-J). In this respect, the New Zealand specimens representing the Pa element are more comparable with those referred to the E. foliaceus-E. reclinatus transition by Bergström (1983, fig. 2). One of the most distinctive characters of the Pa elements of Y. foliaceus is that the distal end of the posterolateral process tends to curve anteriorly, as shown by the topotype dextral Pa element illustrated by Bergström (1971a, pl. 1 fig. 10;

315

AAP Memoir 42 (2011) also Lindström in Ziegler 1977, Eoplacognathus –plate 1, fig. 4). In the Maruia material, this feature is well shown in specimens representing the dextral Pa element (Fig. 16B, D, H, K) and also the sinistral Pa element (Fig. 16E, J).

Investment & Regional Infrastructure (Office of Resources and Energy). Dr Guillermo Albanesi (CONICET, Argentina) and an anonymous referee are thanked for their constructive and helpful comments. This is a contribution to IGCP Project 591: The Early to Middle Palaeozoic Revolution.

Yangtzeplacognathus sp. (Fig. 18A-J) REFERENCES

Material. Seven specimens recovered from samples CN555 and CN497 (see Table 1). Remarks. Only sinistral Pa and dextral Pb elements of this species were recovered, and show close resemblance to Y. foliaceus, but with a more prominent cusp (Fig. 18A, F, J) and narrower platform (Fig. 18B-C, E, G), and a less developed, short posterolateral process of the Pa element with only one (or rarely two) denticles (Fig. 18B-C, H). CONCLUSIONS A middle to late Darriwilian age (extending from the E. suecicus Zone to the Y. foliaceus Subzone of the basal P. serra Zone) is deduced for the upper part of the Sluice Box Formation, exposed in the Maruia – Lake Daniels – Springs Junction area of the southwest Nelson region, New Zealand. This age determination is well supported by recovery of several biostratigraphically important zonal index species of conodonts. In particular, the occurrence of age-diagnostic forms like Pygodus serra, P. anitae, Eoplacognathus suecicus, Yangtzeplacognathus foliaceus and Histiodella kristinae allows precise correlation of these faunas with those from the Thompson Creek area in the northern Takaka Terrane of the South Island (Zhen et al. 2009b) and from central New South Wales (Zhen & Percival 2004a, b), and also internationally with well documented faunas from Baltoscandia (Bergström 1971a, b, 1983;Löfgren 1978, 2004; Viira et al. 2001; Viira 2011; Zhang 1998b, c, 1999) and South China (Ding et al. in Wang 1993; Zhang, 1998a). ACKNOWLEDGEMENTS Study of conodonts by Y. Zhen was partially supported by the CAS/SAFEA International Partnership Program for Creative Research Teams. SEM work was carried out at the Electron Microscope Unit of the Australian Museum. J. Simes and R. Cooper were supported by the New Zealand Geological Survey (now GNS Science). For part of the field work they were accompanied by N. Newman, N. Powell, J. Newman, G. Grindley, R. Brathwaite and R. Farmer. Ian Percival publishes with the permission of the Executive Director, Geological Survey of New South Wales, NSW Department of Trade,

Agematsu, S., Sashida, K. & Ibrahim, A.B., 2008a. Biostratigraphy and paleobiogeography of Middle and Late Ordovician conodonts from the Langkawi Islands, northwestern Peninsular Malaysia. Journal of Paleontology 82, 957–973. Agematsu, S., Sashida, K., Salyapongse, S. & Sardsud, A., 2006. Ordovician conodonts from the Thong Pha Phum area, western Thailand. Journal of Asian Earth Sciences 26, 49–60. Agematsu, S., Sashida, K. & Sardsud, A., 2008b. Reinterpretation of Early and Middle Ordovician conodonts from the Thong Pha Phum area, western Thailand, in the context of new material from western and northern Thailand. Paleontological Research 12(2), 181–194. Albanesi, G.L. & Barnes, C.R., 2000. Subspeciation within a punctuated equilibrium evolutionary event: phylogenetic history of the Lower-Middle Ordovician Paroistodus originalis-P. horridus complex (Conodonta). Journal of Paleontology 74, 492–502. Albanesi, G.L., Hünicken, M.A. & Barnes, C.R., 1998. Bioestratigrafia, biofacies y taxonomia de conodontes de las secuencias Ordovicicas del Cerro Porterillo, Precordillera central de San Juan, R. Argentina. Actas de la Academia Nacianal de Ciencias 12, 7–72. A lbanesi , G.L. & O rtega , G., 2002. Advances on conodont-graptolite biostratigraphy of the Ordovician System of Argentina. 143–166 in F.G. Aceńolaza (ed.), Aspects of the Ordovician System in Argentina. INSUGEO, Série Correlación Geológica 16. An, T.X., 1981. Recent progress in Cambrian and Ordovician conodont biostratigraphy of China. Geological Society of America Special Paper 187, 209–226. An, T.X., 1987. Early Paleozoic conodonts from south China. Peking University Publishing House, Beijing, 238 p. An, T.X. & Ding, L.S., 1982. Preliminary studies and correlations on Ordovician conodonts from the Ningzhen Mountains, China. Acta Petroleum Sinica 3(4), 1–11. An, T.X., Du, G.Q., Gao, Q.Q., Chen, X.B. & Li, W.T., 1981. Ordovician conodont biostratigraphy of the Huanghuachang area of Yichang, Hubei. 105-113 in Micropalaeontological Society of China (ed.), Selected Papers of the First Symposium of the Micropalaeontological Society of China. Science

316 Press, Beijing. An, T.X., Zhang, F., Xiang, W.D., Zhang, Y.Q., Xu, W.H., Zhang, H.J., Jiang, D.B., Yang, C.S., Lin, L.D., Cui, Z.T. & Yang, X.C., 1983. The Conodonts of North China and the Adjacent Regions. Science Press, Beijing, 223 p. An, T.X. & Zheng, S.C., 1990. The conodonts of the marginal areas around the Ordos Basin, north China. Science Press, Beijing, 199 p. Bagnoli, G. & Stouge, S., 1996. Lower Ordovician (Billingenian – Kunda) conodont zonation and provinces based on sections from Horns Udde, north Öland, Sweden. Bollettino della Società Paleontologica Italiana 35, 109–163. Barnes, C.R. & Poplawski, M.L.S., 1973. Lower and Middle Ordovician conodonts from the Mystic Formation, Québec, Canada. Journal of Paleontology 47, 760–790. Bergström, S.M., 1971a. Conodont biostratigraphy of the Middle and Upper Ordovician of Europe and Eastern North America. Geological Society of America Memoir 127, 83–157. Bergström, S.M., 1971b. Correlation of the North Atlantic Middle and Upper Ordovician conodont zonation with the graptolite succession. Mémoires du Bureau de recherches géologiques et minières 73, 177–187. Bergström, S.M., 1973. Biostratigraphy and facies relations in the lower Middle Ordovician of easternmost Tennessee. American Journal of Science 273-A, 261–293. Bergström, S.M., 1983. Biogeography, evolutionary relationships, and biostratigraphic significance of Ordovician platform conodonts. Fossils and Strata 15, 35–58. B ergström , S.M., 1990. Biostratigraphic and biogeographic significance of Middle and Upper Ordovician conodonts in the Girvan succession, south-west Scotland. Courier Forschungsinstitut Senckenberg 118, 1–43. Bergström, S.M., 2007a. Middle and Upper Ordovician conodonts from the Fågelsång GSSP, Scania, southern Sweden. GFF 129, 77–82. Bergström, S.M., 2007b. The Ordovician conodont biostratigraphy of the Siljan region, south-central Sweden: a brief review of an international reference standard. 26–41 and 63–78 in Ebbestad, J.O.R., Wickström, L.M. & Högström, A.E.S. (eds), WOGOGOB 2007, 9th meeting of the Working Group on Ordovician Geology of Baltoscandia, Field Guide and Abstracts. Sveriges Geologiska Undersökning, Rapporter och Meddelanden 128. Bergström, S.M., Chen, X., Gutiérrez-Marco, J.C & Dronov, A., 2009. The new chronostratigraphic classification of the Ordovician System and its relations to major regional series and stages and to δ13C chemostratigraphy. Lethaia 42, 97–107. B ergström , S.M., R iva , J. & K ay , M., 1974.

AAP Memoir 42 (2011) Significance of conodonts, graptolites, and shelly faunas from the Ordovician of Western and Northcentral Newfoundland. Canadian Journal of Earth Sciences 11, 1625–1660. Burrett, C., Stait, B. & Laurie, J., 1983. Trilobites and microfossils from the Middle Ordovician of Surprise Bay, southern Tasmania, Australia. Memoirs of the Association of Australasian Palaeontologists 1, 177–193. C awood , P.A., 1976. Cambro-Ordovician strata, northern New South Wales. Search 7, 317–318. Chen, M.J. & Zhang, J.H., 1984a. On two evolutionary continuums of conodonts in the Middle Ordovician. Journal of Nanjing University (Natural Science) 1984 (2), 327–334. Chen, M.J. & Zhang, J.H., 1984b. Middle Ordovician conodonts from Tangshan, Nanjing. Acta Micropalaeontologica Sinica 6, 213–228. Cocks, L.R.M. & Cooper, R.A., 2004. Late Ordovician (Hirnantian) shelly fossils from New Zealand and their significance. New Zealand Journal of Geology and Geophysics 47, 71–80. Cooper, R.A., 1979. Ordovician geology and graptolite faunas of the Aorangi Mine area, North-west Nelson, New Zealand. New Zealand Geological Survey Paleontological Bulletin 47, 1–127. Cooper, R.A., 1989. Early Paleozoic terranes of New Zealand. Journal of the Royal Society of New Zealand 19, 73–112. C ooper , R.A. & B radshaw , M.A., 1986. Lower Paleozoic of Nelson-Westland. Geological Society of New Zealand Miscellaneous Publication 33C, 1–42. Cooper, R.A. & Druce, E.C., 1975. Lower Ordovician sequence and conodonts, Mount Patriarch, Northwest Nelson, New Zealand. New Zealand Journal of Geology and Geophysics 18, 551–582. Cooper, R.A. & Tulloch, A.J., 1992. Early Palaeozoic terranes in New Zealand and their relationship to the Lachlan Fold Belt. Tectonophysics 214, 129–144. Du, P.D., Zhao, Z.X., Huang, Z.B., Tan, Z.J., Wang, C., Yang, Z.L., Zhang, G.Z. & Xiao, J.N., 2005. Discussion on four conodont species of Histiodella from Tarim Basin and their stratigraphic implication. Acta Micropalaeontologica Sinica 22, 357–369. Dzik, J., 1976. Remarks on the evolution of Ordovician conodonts. Acta Palaeontologica Polonica 21, 395–455. D zik , J., 1978. Conodont biostratigraphy and paleogeographical relations of the Ordovician Mójcza Limestone (Holy Cross Mts, Poland). Acta Palaeontologica Polonica 23, 51–72. Dzik, J., 1994. Conodonts of the Mójcza Limestone. Palaeontologia Polonica 53, 43–128. Epstein A.G., J.B. Epstein & L.D. Harris. 1977. Conodont color alteration - An index to organic metamorphism. United States Geological Survey Professional Paper 995, 1–27.

AAP Memoir 42 (2011) F å h r æ u s , L.E., 1966. Lower Viruan (Middle Ordovician) conodonts from the Gullhögen Quarry, Southern Central Sweden. Sveriges Geologiska Undersökning C 610, 1–40. Fåhræus, L.E. & Hunter, D.R., 1985. Simple-cone conodont taxa from the Cobbs Arm Limestone (Middle Ordovician), New World Island, Newfoundland. Canadian Journal of Earth Sciences 22, 1171–1182. Farmer, R.T., 1967. Stratigraphy and structure of Palaeozoic rocks near Springs Junction, southwest Nelson. Unpublished Ph.D. thesis, University of Canterbury, Christchurch, 178 p. Gao, Q.Q., 1991. Conodonts. 125-149 in Xinjiang Petroleum Administration Bureau and the Jianghan Petroleum Administration Bureau (ed.), Sinian to Permian stratigraphy and Palaeontology of the Tarim Basin II, Keping-Bachu area. Petroleum Industry Press, Beijing. G raves , R.W. & E llison , S., 1941. Ordovician conodonts of the Marathon Basin, Texas. University of Missouri, School of Mines and Metallurgy, Bulletin of the Technical Series 14, 1–26. Hadding, A.R., 1913. Undre dicellograptusskiffern i Skåne jämte några dågra därmed ekvivalenta bildningar. Lunds Universitets Årsskrift, Ny Följd, Afdelning 2, 9(15), 1–90. Hamar, G., 1966. The Middle Ordovician of the Oslo region, Norway 22. Preliminary report on conodonts from the Oslo-Asker and Ringerike districts. Norsk Geologisk Tidsskrift 46, 27–83. H arris , R.W., 1962. New conodonts from Joins (Ordovician) Formation of Oklahoma. Oklahoma Geology Notes 22, 199–211. Harris, A.G., Bergström, S.M., Ethington, R.L. & Ross, R.J., 1979. Aspects of Middle and Upper Ordovician conodont biostratigraphy of carbonate facies in Nevada and southeast California and comparison with some Appalachian successions. Brigham Young University Geology Studies 26, 7–43. H eredia , S., P eralta , S. & B eresi , M., 2005. Darriwilian conodont biostratigraphy of the Las Chacritas Formation, Central Precordillera (San Juan Province, Argentina). Geologica Acta 3(4), 385–394. Jaanusson, V. & Bergström, S.M., 1980. Middle Ordovician faunal spatial differentiation in Baltoscandia and the Applachians. Alcheringa 4, 89–110. Jongens, R. 2006. Structure of the Buller and Takaka Terrane rocks adjacent to the Anatoki Fault, northwest Nelson, New Zealand. New Zealand Journal of Geology and Geophysics 49, 443–461. Landing, E., 1976. Early Ordovician (Arenigian) conodont and graptolite biostratigraphy of the Taconic allochthon, eastern New York. Journal of Paleontology 50, 614–646.

317 L ee , H.Y., 1975. Conodonten aus dem unteren und mittleren Ordovizium von Nordkorea. Palaeontographica A 150, 161–186. Lehnert, O., 1995. Ordovizische Conodonten aus der Präkordillere Westargentiniens: Ihre Bedeutung für Stratigraphie und Paläogeographie. Erlanger Geologische Abhandlungen 125, 1–193. L ehnert , O., B ergström , S.M., K eller , M. & Bordonaro, O., 1999. Ordovician (DarriwilianCaradocian) conodonts from the San Rafael Region, west-central Argentina: biostratigraphic, paleoecologic, and paleogeographic implications. Bullettino della Soceità Paleontologica Italiana 37, 199–214. Lindström, M., 1955. Conodonts from the lowermost Ordovician strata of south-central Sweden. Geologiska Föreningens i Stockholm Förhandlingar 76, 517–604. Lindström, M., 1964. Conodonts. Elsevier Publishing Company, Amsterdam, 196 p. Lindström, M., 1971. Lower Ordovician conodonts of Europe. Geological Society of America, Memoir 127, 21–61. L öfgren , A., 1978. Arenigian and Llanvirnian conodonts from Jämtland, northern Sweden. Fossils and Strata 13, 1–129. L öfgren , A., 1990. Non-platform elements of the Ordovician conodont genus Polonodus. Paläontologische Zeitschrift 64, 245-259. Löfgren, A., 2004. The conodont fauna in the Middle Ordovician Eoplacognathus pseudoplanus Zone of Baltoscandia. Geological Magazine 141, 505–524. Löfgren, A. & Tolmacheva, T.J., 2003. Taxonomy and distribution of the Ordovician conodont Drepanodus arcuatus Pander, 1856, and related species. Paläontologische Zeitschrift 77, 203–221. McCracken, A.D., 1991. Middle Ordovician conodonts from the Cordilleran Road River Group, northern Yukon Territory, Canada. Geological Survey of Canada, Bulletin 417, 41–63. M ellgren , J. & E riksson , M.E., 2006. A model of reconstruction for the oral apparatus of the Ordovician conodont genus Protopanderodus Lindström, 1971. Transactions of the Royal Society of Edinburgh: Earth Sciences 97, 97–112. Münker, C. & Cooper, R.A. 1999. The Cambrian arc complex of the Takaka Terrane, New Zealand: an integrated stratigraphical, paleontological and geochemical approach. New Zealand Journal of Geology and Geophysics 42, 415–445. N athan , S., R attenbury , M.S. & S uggate , R.P., 2002. Geology of the Greymouth area. Institute of geological and Nuclear Sciences 1:250 000 geological map of New Zealand, map 12. Institute of Geological and Nuclear Sciences, Lower Hutt. N i , S.Z., 1981. Discussion on some problems of Ordovician stratigraphy by means of conodonts in eastern part of Yangtze Gorges Region. 127–

318 134 in Micropalaeontological Society of China (ed.), Selected papers on the 1st Convention of Micropalaeontological Society of China. Science Press, Beijing. Nicoll, R.S., 1980. Middle Ordovician conodonts from the Pittman Formation, Canberra, ACT. BMR Journal of Australian Geology & Geophysics 5, 150–153. Nicoll, R.S. & Shergold, J.H., 1991. Revised Late Cambrian (pre-Payntonian-Datsonian) conodont biostratigraphy at Black Mountain, Georgina Basin, western Queensland, Australia. BMR Journal of Australian Geology & Geophysics 12, 93–118. N owlan , G.S. & T hurlow , J.G., 1984. Middle Ordovician conodonts from the Buchans Group, central Newfoundland, and their significance for regional stratigraphy of the Central Volcanic Belt. Canadian Journal of Earth Sciences 21, 284–296. Ortega, G., Albanesi, G.L. & Frigerio, S.E., 2007. Graptolite-conodont biostratigraphy and biofacies of the Middle Ordovician Cerro Viejo succession, San Juan Precordillera, Argentina. Palaeogeography, Palaeoclimatology, Palaeoecology 245, 245–263. Ortega, G., Albanesi, G.L., Banchig, A.L. & Peralta, G.L., 2008. High resolution conodont-graptolite biostratigraphy in the Middle-Upper Ordovician of the Sierra de la Invernada Formation (Central Precordillera, Argentina). Geologica Acta 6(2), 161–180. Ottone, E.G., Albanesi, G.L., Ortega, G. & Holfeltz, G.D., 1999. Palynomorphs, conodonts and associated graptolites from the Ordovician Los Azules Formation, Central Precordillera, Argentina. Micropaleontology 45, 225–250. Pander, C.H., 1856. Monographie der fossilen Fische des Silurischen Systems der Russisch-Baltischen Gouvernements. Akademie der Wissenschaften, St. Petersburg, 91 p. Percival, I.G., Wright, A.J., Simes, J.E., Cooper, R.A. & Z hen , Y.Y., 2009. Middle Ordovician (Darriwilian) brachiopods and trilobites from Thompson Creek, northwest Nelson, New Zealand. Memoirs of the Association of Australasian Palaeontologists 37, 611–639. P ercival , I.G. & Z hen , Y.Y., 2007. Darriwilian conodonts of Eastern Australia: biostratigraphy and biogeographic distribution. Acta Palaeontologica Sinica 46 (Supplement), 387–392. Pickett, J. & Percival, I.G., 2001. Ordovician faunas and biostratigraphy in the Gunningbland area, central New South Wales. Alcheringa 25, 9–52. Pohler, S.M.L. & Orchard, M.J., 1990. Ordovician conodont biostratigraphy, western Canadian Cordillera. Geological Survey of Canada Paper 90-15, 1–37. Pyle, L.J. & Barnes, C.R., 2003. Conodonts from a platform-to-basin transect, Lower Ordovician to Lower Silurian, northeastern British Columbia,

AAP Memoir 42 (2011) Canada. Journal of Paleontology 77, 146–171. Rasmussen, J.A., 2001. Conodont biostratigraphy and taxonomy of the Ordovician shelf margin deposits in the Scandinavian Caledonides. Fossils and Strata 48, 1–180. Simes, J.E., 1980. Age of the Arthur Marble: conodont evidence from Mount Owen, northwest Nelson. New Zealand Journal of Geology and Geophysics 23, 529–532. Stouge, S., 1984. Conodonts of the Middle Ordovician Table Head Formation, western Newfoundland. Fossils and Strata 16, 1–145. Sweet, W.C. & Bergström, S.M., 1962. Conodonts from the Pratt Ferry Formation (Middle Ordovician) of Alabama. Journal of Paleontology 36, 1214– 1252. Viira, V., 1967. Ordovician conodont succession in the Ohesaare core. Eesti NSV teaduste Akadeemia Toimetised, Keemia Geoloogia 16 (4), 319–329. Viira, V., 1974. Konodonty ordovika Pribaltiki. Valgus, Tallinn, 142 p. V iira , V., 2011. Lower and Middle Ordovician conodonts from the subsurface of SE Estonia and adjacent Russia. Estonian Journal of Earth Sciences 60, 1–21. Viira, V., Löfgren, A., Mägi, S. & Wickström, J., 2001. An Early to Middle Ordovician succession of conodont faunas at Mäekalda, northern Estonia. Geological Magazine 138, 699–718. Wang, C.Y. (ed.), 1993. Conodonts of the Lower Yangtze Valley - an index to biostratigraphy and organic metamorphic maturity. Science Press, Beijing, 326 p., 60 pls. Wang, Z.H. & Lou, K.Q., 1984. Late Cambrian and Ordovician conodonts from the Marginal areas of the Ordos Platform, China. Bulletin of Nanjing Institute of Geology and Palaeontology, Academia Sinica 8, 237–304. Wang, Z.H. & Zhou, T.R., 1998. Ordovician conodonts from western and northeastern Tarim and their significance. Acta Palaeontologica Sinica 37, 173–193. Watson, S.T., 1988. Ordovician conodonts from the Canning Basin (W. Australia). Palaeontographica A203, 91–147. Wright, A.J., 1968. Ordovician conodonts from New Zealand. Nature 218, 664–665. Wright, A.J., C ooper, R.A. & Simes, J.E., 1994. Cambrian and Ordovician faunas and stratigraphy, Mt Patriarch, New Zealand. New Zealand Journal of Geology and Geophysics 37, 437–476. Zhang, J.H., 1998a. Conodonts from the Guniutan Formation (Llanvirnian) in Hubei and Hunan Provinces, south-central China. Stockholm Contributions in Geology 46, 1–161. Z hang , J.H., 1998b. Four evolutionary lineages of the Middle Ordovician conodont family Polyplacognathidae. Meddelanden från Stockholms

AAP Memoir 42 (2011) Universitets Institution för Geologi och Geokemi 298 (Paper 5), 1–35. Zhang, J.H., 1998c. The Ordovician conodont genus Pygodus. Palaeontologia Polonica 58, 87–105. Zhang, J.H. & Sturkell, E.F.F., 1998. Aserian and Lasnamägian (Middle Ordovician) conodont biostratigraphy and lithology at Kullstaberg and Lunne in Jämtland, central Sweden. GFF 120, 75–83. Zhang, J.H., 1999. Review of the Ordovician conodont zonal index Eoplacognathus suecicus Bergström. Journal of Paleontology 73, 487–493. Zhao, Z.X., Zhang, G.Z. & Xiao, J.N., 2000. Paleozoic stratigraphy and conodonts in Xinjiang. Petroleum Industry Press, Beijing, 340 p. Zhen, Y.Y. & Percival, I.G., 2004a. Middle Ordovician (Darriwilian) conodonts from allochthonous limestones in the Oakdale Formation of central New South Wales, Australia. Alcheringa 28, 77–111. Z hen , Y.Y. & P ercival , I.G., 2004b. Darriwilian (Middle Ordovician) conodonts from the Weemalla Formation, south of Orange, New South Wales. Memoirs of the Association of Australasian Palaeontologists 30, 153–178. Z hen , Y.Y., P ercival , I.G., C ooper , R.A., S imes , J.E. & Wright, A.J., 2009b. Darriwilian (Middle

319 Ordovician) conodonts from Thompson Creek, Nelson Province, New Zealand. Memoirs of the Association of Australasian Palaeontologists 37, 25–53. Zhen, Y.Y., Percival, I.G. & Webby, B.D., 2004. Conodont faunas from the Mid to Late Ordovician boundary interval of the Wahringa Limestone Member (Fairbridge Volcanics), central New South Wales. Proceedings of the Linnean Society of New South Wales 125, 141–164. Zhen, Y.Y. & Pickett, J.W., 2008. Ordovician (Early Darriwilian) conodonts and sponges from west of Parkes, central New South Wales. Proceedings of the Linnean Society of New South Wales 129, 57–82. Zhen, Y.Y., Wang, Z.H., Zhang, Y.D., Bergström, S.M., Percival, I.G. & Chen, J.F., 2011. MiddleLate Ordovician (Darriwilian-Sandbian) conodonts from the Dawangou Section, Kalpin area of the Tarim Basin, northwestern China. Records of the Australian Museum 63, 203–266. Zhen, Y.Y., Zhang, Y.D. & Percival, I.G., 2009a. Early Sandbian (Late Ordovician) conodonts from the Yenwashan Formation, western Zhejiang, South China. Alcheringa 33, 133–161. Ziegler, W. (ed.), 1977. Catalogue of conodonts, Vol. III. Schweizerbart’sche, Stuttgart, 574 p.