Poland (Holy Cross Mts, Cracow Upland, Sude- tes; varcus ... Quarry in the Holy Cross Mrs. .... (Russian Academy of Sciences, Ufa), A. Kuzmin, M. Sc. (VNIGNI ...
MIDDLE/LATE DEVONIAN PHOEBODONTBASED ICHTHYOLITH ZONATION.
MICHA G I N T E R &/~LEXANDER l V A N O V GINTER M. & IVANOV A. 1995. Middle/Late Devonian Phoebodont-based ichthyolith zonation. [Zonation ichthyologique du D~vonien moyen/sup~rieur fond~e sur les Phoebodontes]. GEOBIOS, M.S. n ° 19 : 351-355. ABSTRACT A subdivision of the upper part of the Devonian (varcus through praesulcata conodont zones) into six ichthyolith zones is proposed. The zonation is based on the stratigraphic ranges of elasmobranch teeth from the pelagic facies of Central and Eastern Europe. Species of the genus Phoebodus were chosen as index taxa. A gap in the zonation in the lowermost Famennian is caused by the temporary absence of phoebodonts on the studied areas. The scarcity of phoebodont remains begins already in the uppermost Frasnian linguiformis zone, and may tentatively be correlated to the Kellwasser event. Two new species of Phoebodus are introduced. KEY-WORDS : ELASMOBRANCHS,PHOEBODONTS,DEVONIAN, BIOZONATION,STRATIGRAPHICCORRELATION, BIOEVENT. RI~SUME Les auteurs proposent de diviser la partie sup~rieure du D~vonien (de la zone de Conodontes ~ varcus ~ la zone praesulcata) en six zones ichthyologiques. Cette division est fond~e sur la r~partition stratigraphique des dents d'Elasmobranches qui se r~coltent dans les facies p~lagiques de l'Europe Centrale et Orientale. Ce sont les esp~ces du genre Phoebodus qui sont choisies comme esp~ces index. Dans les r~gions ~tudi~es, les restes de Phoebodontes sont tr~s rares d~s la zone ~ linguiformis du Frasnien terminal, ce qui est mis en relation, de fa~on hypoth~tique, avec l'~v~nement Kellwasser. Cette raret~ se poursuit jusqu'~ la base du Famennien. Deux esp~ces nouvelles de Phoebodus sont introduites. MOTS-CL]~S : ELASMOBRANCHES,PHOEBODONTES, D]~VONIEN,BIOZONATION, CORR]~LATIONSTRATIGRAPHIQUE, CRISE BIOLOGIQUE.
The provisional ichthyolith zonation for the Central and E a s t e r n Europe pr es e nt e d below is mainly based on the stratigraphic ranges of t he selected species of th e Devonian s h a r k genus Phoebodus. Phoebodont t e e t h are characterised by the highest frequency, diversity and evolutionary variability from all t he ichthyoliths studied by us. Most of phoebodont species have precisely defined ranges an d are cosmopolitan in pelagic facies. T h a t is w h y t h e y were chosen as index t axa for the zonation. Teeth of t h e other sharks, such as T h r i n a c o d u s , O m a l o d u s , symmoriids and protacrodontids as well as onychodontid t e e t h were also used in the construction of th e zonation and play a role of associated taxa. The r e m a i n i n g fish microfossils :
shark scales and denticles, palaeoniscoid scales and teeth, acanthodian scales and fin-spines, placoderm denticles and thelodont scales, seem to have no or little biostratigraphic significance because of their low frequency and/or variability, or long stratigraphic ranges. The studied material comes from the upper Givetian through F a m e n n i a n of t he s o u t h e r n part of Poland (Holy Cross Mts, Cracow Upland, Sudetes; varcus - p r a e s u l c a t a conodont zones), and from the Urals and the T i m a n (hassi - praesulcata zones). P r e l i m i n a r y res'ults of the studies of the first aut hor on Dr. D. Weyer's collection from the upper F a m e n n i a n of G e r m a n y (Thuringia, Rhenish Slate Mountains) were also t a k e n into account.
352 More t h a n 350 of 400 positive s a m p l e s r e p r e s e n t the interval between the upper Frasnian and the u p p e r m o s t F a m e n n i a n (late hassi - middle praesulcata conodont zones). T h e s a m p l e s are u s u a l l y well d a t e d b y conodonts a n d t h e b o u n d a r i e s bet w e e n t h e i c h t h y o l i t h zones proposed h e r e i n could be defined w i t h a precision of +/- one conod o n t zone. All t h e i c h t h y o l i t h zones are intervalbiozones sensu H e d b e r g (1979). O u r doubts conc e r n i n g t h e precision of t h e position of boundaries are p r e s e n t e d in t h e r e m a r k s to the definitions of zones, h e r e below. T h e figured s p e c i m e n s are h o u s e d in the Institut e of Geology, W a r s a w U n i v e r s i t y ( a b b r e v i a t e d as I G P U W ) in W a r s a w ; D e p a r t m e n t of E a r t h Sciences, Silesian U n i v e r s i t y (GIUS) in Sosnowiec ; a n d L a b o r a t o r y of Palaeontology, St. P e t e r s b u r g U n i v e r s i t y (LP) in St. P e t e r s b u r g . F o r the descriptions o f i n d e x t a x a : see references.
DEFINITIONS
OF ZONES
Phoebodus sophiae zone. I n d e x t a x o n : Phoebodus sophiae ST. JOHN & WORTHEN, 1875 (here P1. 1, fig. 1, 2 ). Associated t a x a : first occurrence of Ph. fastigatus; Omalodus bryanti is c h a r a c t e r i s t i c of t h e low e r p a r t o f t h e zone ; Strunius rolandi a p p e a r s in t h e F r a s n i a n . L o w e r l i m i t : first occurrence of Ph. sophiae. U p p e r limit : first o c c u r r e n c e of Ph. latus nov. sp. Reference sections : L a s k o w a Hill a n d W i e t r z n i a Q u a r r y in t h e H o l y Cross Mrs. C o r r e s p o n d i n g conodont zones : middle or late varcus to punctata zones. R e m a r k s : t h e u p p e r p a r t of sophiae zone (since t h e end o f t h e G i v e t i a n ) is poorly d o c u m e n t e d . T h e index t a x o n h a s not y e t b e e n found in this p a r t of this zone. T h e occurence of Ph. fastigatus t o g e t h e r w i t h t e e t h o f Strunius rolandi, and t h e
absence of Ph. latus nov. sp. or Ph. bifurcatus m a y be a w e a k indicator of t h a t interval.
Phoebodus latus zone. I n d e x t a x o n : Phoebodus latus nov. sp. (P1. 1, fig. 3, 4). Associated t a x a : Ph. fastigatus, Strunius rolandi. L o w e r limit : first occurrence ofPh. latus nov. sp. U p p e r limit : first occurrence of Ph. bifurcatus. R e f e r e n c e section: R y a u z y a k River, w e s t e r n slope of t h e S o u t h Urals. C o r r e s p o n d i n g conodont zones : late hassi - j a mieae zones. Phoebodus bifurcatus zone. I n d e x t a x o n : Phoebodus bifurcatus GINTER & IVANOV, 1992 (here P1. 1, figs 5, 6). Associated t a x a : Ph. latus nov. sp., Ph. fastigatus, Protacrodus vetustus, Stethacanthus cf. S. thomasi, Strunius rolandi. L o w e r limit : first occurrence ofPh. bifurcatus. U p p e r limit : last occurrence of Ph. bifurcatus. R e f e r e n c e section : R y a u z y a k River, w e s t e r n slope of t h e S o u t h Urals. C o r r e s p o n d i n g conodont zones : e a r l y rhenana linguiforrnis zones. R e m a r k s : P h o e b o d o n t s are v e r y r a r e in t h e linguiformis conodont zone a n d t h e y w e r e f o u n d t h e r e only in t h e Urals. P r o b a b l y t h e i r occurrence in t h e studied a r e a s is limited to t h e l o w e r p a r t of t h a t zone. T h e i r s u b s e q u e n t d i s a p p e a r a n c e was possibly c a u s e d by t h e K e l l w a s s e r - e v e n t , w h o s e effect is m u c h b e t t e r visible in P o l a n d and G e r m a n y t h a n on t h e e a s t e r n m a r g i n of the Platform. Non-phoebodont interval C h a r a c t e r i s t i c i c h t h y o l i t h t a x a : Stethacanthus cf. S. thomasi, P. vetustus, h y b o d o n t scales, palaeoniscoid scales of Moythomasia type, a b u n d a n t Acanthodes-type scales. No phoebodonts. L o w e r l i m i t : l a s t occurrence ofPh. bifurcatus.
P~TE1 Representatives of index taxa of the Phoebodont-based zones of the Middle/Upper Devonian. Reprgsentants des
taxa-index des zones de Phoebodontes du Ddvonien moyen/supdrieur. Figs. 1, 2 - Phoebodus sophiae ST. JOHN & WORTHEN, Laskowa Hill (Holy Cross Mts, Poland), sample L-II/a, Middle or Late varcus Zone, specimen GIUS-4-412/102, x 40. Figs. 3, 4 - Phoebodus latus nov. sp., 3 Kadzielnia (Holy Cross Mts, Poland), sample K-MB-Mantic., rhenana zone, specimen IGPUW/Ps/1/89, x 30 ; 4, Ryauzyak (South Urals, Russia), sample 6394, rhenana zone, specimen LP 13-2, x 30. Figs. 5, 6 - Phoebodus bifurcatus GINTER & IVANOV, 5, Kuk-Karauk (South Urals, Russia), rhenana zone, specimen LP 7-10, x 30 ; 6, Vezha-vozh (Timan, Russia), rhenana zone, specimen LP 7-7, x 45. Fig. 7 - Phoebodus typieus nov. sp., Ryauzyak (South Urals, Russia), sample 6478, rhomboidea zone, specimen LP 7-19 (holotype), x 60. Fig. 8 - Phoebodus gothicus GINTER,Kuk-Karauk (South Urals, Russia), postera zone, specimen LP 7-26, x 30. Figs. 9, 10 - Phoebodus limpidus GINTER, 9, Ostr6wka (Holy Cross Mts, Poland), sample F-9, late expansa or early praesulcata zones, specimen IGPUW/Ps/39, x 80 ; 10, Ostr6wka (Holy Cross Mts, Poland), sample F-11, specimen IGPUW/Ps/40, x 80. Scale bar = 0.2 turn.
P1. 1 M. G i n t e r & A. I v m l o v
Geobios M.S. n ° 19
5
mmmm
~
354 Table 1 - P h o e b o d o n t - b a s e d ichthyolith zonation of t h e STAGES AND CONODONT ZONES
praesulcata
expansa postera
ICHTHYOLITH ZONES
L M E L M E L
~"
marginifera
Lo L E
rhomboidea
crepida
triangularis
fimpMus
Phoebodus limpidus Ph. ? austmliensis, Ph. gothicus, Symmorium sp., Thdnacodus sp. nov., Th. ferox
gothicus
Phoebodus gothicus Ph. typicus, Ph. turnerae, Th. sp. nov., Symmorium sp., Protacrodus vetustus
typicus
Phoebodus typicus Ph. tumerae, Stethacanthus sp., S. cf. thomasi, Symmonum sp., Protacrodus vetustus
L
trachytera
L E L* L M E L ME
non-phoebodont interval
linguiformis rhenana jamieae
~(~
hassi
L --
E L
INDEX TAXON AND MAIN ASSOCIATED TAXA
(Stethacanthus cf. thomasL P. vetustus)
bifurcatus
Ph. bifurcatus Ph. latus, Ph. fastigatus, S. cf. thomasi, P. vetustus
latus
Phoebodus latus Ph. fastigatus
sophiae
Phoebodus sophiae Ph. fastigatus, Omalodus bryanti
E
Middle/Upper D e v o n i a n . Biozonation du Ddvonien moyen! supdrieur fondde sur les Phoebodontes.
~_ _punctata transitans falsiovafis
~_. LLI >
(.9
disparilis hermanni - ctistatus .v~cu~
L -E L E L
-~ E
U p p e r limit : first occurrence of Ph. typicus nov.
denticles. Last occurrences of Stethacanthus cf. S.
sp.
thomasi and S. rolandi.
Reference sections : R y a u z y a k River at the w e s t e r n Slope of the S o u t h Urals ; Psie GSrki Hills and Pucki in t h e H o l y Cross Mts. Corresponding c o n o d o n t zones : (? linguiformis) early - middle triangularis zones.
Lower ]imit : first occurrence of Ph. typicus nov.
Phoebodus typicus zone. Index t a x o n : Phoebodus typicus nov. sp. (P1. 1, fig. 7). Associated t a x a : First occurrences of Ph. turnerae, Stethacanthus sp., and in the upper part Symmorium sp. a n d Stemmatias-type branchial
sp.
U p p e r limit : first occurrence ofPh. gothicus. Reference section : R y a u z y a k River, w e s t e r n slope of t h e S o u t h Urals. Corresponding conodont zones : late triangularis to rhomboidea zones.
Phoebodus gothicus zone. Index t a x o n : Phoebodus gothicus GINTER, 1990 (here P1. 1, fig. 8). Associated t a x a : Symmorium sp., first occurren-
355 ces o f P h . ? australiensis a n d Thrinacodus nov. sp. sensu G i n t e r in press. L a s t occurrences of Ph. turnerae, Ph. typicus nov. sp. a n d Protacrodus vetustus. L o w e r l i m i t : first occurrence ofPh. gothicus. U p p e r l i m i t : first occurrence of Ph. limpidus.
PHOEBODUS TYPICUS NOV. SP. : P1 1, fig. 7.
Reference sections : outcrops in the n o r t h e r n p a r t of LagSw Village in t h e Holy Cross Mts, R y a u z y a k River, w e s t e r n slope of the S o u t h Urals. C o r r e s p o n d i n g conodont zones : e a r l y marginifera to l a t e postera zones.
Diagnosis - t h e b a s e is a l m o s t r e c t a n g u l a r ,
Phoebodus limpidus zone. I n d e x t a x o n : Phoebodus limpidus GINTER, 1990 (here P1. 1, fig. 9, 10). Associated t a x a : Ph. gothicus, Ph.? australiensis, Thrinacodus nov. sp., Symmorium sp. a n d Protacrodus sp. F i r s t occurrence of Th. ferox in t h e upp e r p a r t o f t h e zone. L o w e r l i m i t : first occurrence of Ph. limpidus. U p p e r l i m i t : last occurrence ofPh. limpidus. Reference section : O s t r 6 w k a Q u a r r y in the Holy Cross Mts. C o r r e s p o n d i n g conodont zones : e a r l y expansa middle praesulcata zones. R e m a r k s : All the p h o e b o d o n t s and Thrinacodus nov. sp. d i s a p p e a r b y t h e end of this zone. This was c a u s e d p r o b a b l y by t h e H a n g e n b e r g - e v e n t . In the l a t e praesulcata conodont zone a n d t h e low e r m o s t zones of t h e T o u r n a i s i a n t h e elasmob r a n c h f a u n a seems to be r a t h e r poor and less d i f f e r e n t i a t e d t h a n in t h e late F a m e n n i a n . Th. ferox, Ph.? australiensis a n d p r o t a c r o d o n t s are dom i n a t i n g . T h e l a t e r r a d i a t i o n b e g a n p r o b a b l y in t h e u p p e r p a r t of t h e T o u r n a i s i a n .
covered w i t h few s t r o n g ridges, t h e lingual face is smooth.
H o l o t y p e - specimen LP7-19 from the S o u t h Urals, R y a u z y a k , s a m p l e 6478, F a m e n n i a n , rhomboidea conodont zone. slightly elongated laterally. An oval b u t t o n occupies t h e central p a r t of t h e base. The crown is phoebodont-type a n d consists of t h r e e to five cusps, including small i n t e r m e d i a t e cusplets. Both sides of t h e cusps are covered w i t h subparallel s t r i a e which are s t r o n g e r on the labial surface.
Acknowledgements - The authors are most grateful to Drs. A. Abramova, V. Baryshev and V. Pazukhin (Russian Academy of Sciences, Ufa), A. Kuzmin, M. Sc. (VNIGNI, Moscow), Professor IV[. Szulczewski (Warsaw University), Dr. G. Racki (Silesian University, Sosnowiec) and Dr. D. Weyer (Kulturhistorisches Museum, Magdeburg) who donated their material for investigation and provided stratigraphical information. This is a contribution to IGCP 328. Paleozoic Microvertebrates.
REFERENCES G1NTER M. 1990 - Late Famennian shark teeth from the Holy Cross Mts, Central Poland. Acta Geologica Polonica, 40 : 69-81. GINTER M. (in press) - Ichthyoliths and Late Devonian events in Poland and Germany. Ichthyolith Issues,
Special Edition.
SYSTEMATIC NOTES We give h e r e a short diagnosis of the two new species of Phoebodus i n t r o d u c e d for defining two new biozones. F o r s y n o n y m y , d e r i v a t i o n of names, full descriptions a n d r e m a r k s to b o t h species, see G i n t e r & I v a n o v (in press).
P H O E B O D U S L A T U S NOV. SP. : P1. 1, fig. 3, 4.
Holotype - s p e c i m e n L P 7-16 from t h e S o u t h Urals, R y a u z y a k , s a m p l e 6400, F r a s n i a n , rhenana conodont zone.
Diagnosis - The base is s h o r t (labio-lingually) a n d v e r y wide, r e c t a n g u l a r to trapezoidal. A lat e r a l l y elongates b u t t o n lies close to t h e lingual rim. T h e crown is of p h o e b o d o n t type (i.e. in which t h e t h r e e m a i n cusps are a l m o s t equal) a n d consists o f five to s e v e n cusps, including accessory cusp]ets. T h e labial face of the cusps is
GINTER M. • IVANOVA. 1992 - Devonian phoebodont shark teeth. Acta Palaeontologica Polonica, 37 : 5575. GINTER IV[. ~¢ IVANOVA. (in press) - New Late Devonian species of Phoebodus. Ichthyolith Issues, Spe-
cial Edition. HEDBERG H.D. (ed.) 1979 - Guide stratigraphique in-
ternational. Classification, terminologie et r~gles de procddure. Doin ~dit., Paris : 233 p. ST. JOHN O. & WORTHEN A.H. 1875 - Descriptions of fossil fishes. Geological Survey of Illinois, 6 : 245488.
M. GINTER Instytut Geologii Podstawowej Uniwersytet Warszawski Aleja Zwirki i Wigury 93 02-089 Warszawd, Poland A. IVANOV Laboratory of Palaeontology Institute of the Earth Crust Saint-Petersburg University 16 Linija 29 St Petersburg 199178, Russia
