A new species of Festuca L. (Poaceae) from Liguria ...

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Jun 16, 1995 - Festuca veneris G. Rossi, Foggi & Signorini, sp. nov. Differt ii ..... La vegetnzioize delle Isole Palmaria e Tino (Golfo di La Spezia). Giorn. Bot.
W e b b i a 51(1): 21-29. 1996

A new species of Festuca L. (Poaceae) from Liguria (Italy) '' '

Istituto Botanico dell'Università Via S. Epifanio 14, 1-27100 Pavia ? Orto Botanico dell'università \Ti2 P A. Micheli 3, 1-50121 Firenze ' Dipurtimento di Biologia Vegetale dell'università P.le delle Cascine 28, 1-50144 Firenze

Accettato pei la stampa il 3 luglio 1996 Una nuova specie di Festuca L. (Poaceae) della Liguria (Italia). - Viene descritta una nuova specie d i festuca: Festuca veneris, endemismo delle coste rocciose del promontorio d i Portovenere e dell'Isola d i Palmaria. Vengono riportate le carattcristiche morfologiche, anatomiche, cariologiche, ecologiche e corologiche della specie. Vengono inoltre riassunte le principali cara~teristichedistintive d i F. vetw,ls rispetto alle specie d i F. ovina aggr. morfologicamente più affini. Key woi,ds: Frstzlca, Liguria, Poaceae, Taxonomy.

During recent investigations on the genus Festuca L. (Poaceae) in Italy, we exarnined some specirnens housed in FI and RO, which were collected by Somrnier in 1883 in Liguria at Portovenere. The labels refer to a rnanuscript by Hackel and bear the deterrnination " F . ovina var. glauca subvar. tenuior", a narne \ve could not find in the literature. The specirnens are certainly to be reierred to the sect. Festuca (corresponding to the series Intvavaginales Hack., 1882); in particular, within this section, to the F. ovina aggregate (corresponding to "subsp. eu-ovina" Hack., 1882). As already noticed by Hackel in the rnanuscript, they appear rnorphologically closest to F. glauca Vill., VILLARS (1787) described plants cultivatcd in the Jardin du Roi in Paris, which probably originated frorn plants or fruits collected by Pourret on the sea-cliffs at Roussillon (Southern France, near the Spanish border). AUQUIER& KERGUÉLEN (1977) designated a neotype for this species and reported the chrornosome nurnber 2n = 6 x = 42. Also F. cinevea Vill., F. inops De Not. and F. g~acilior (IIack.) Markgr.-Dann. exhibit some morphological affinity with the fescue s on herbariurn specirnens, freshly colfrom Portovenere. I n ~ e s t i ~ a t i o nbased lected plants and field observations convinced us that the plants collected by

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Research siipported by Consiglio Nazioilale delle Ricerche and by the Italian Miiiisrry fai- Ciii\.c-i-sii\ iind Scicrititic Rcsc.ii.cli (40Oo) "

22

G . ROSSI. B. FOGGI and M.A. SIGNORINI

Sommier are to be ascribed to a new species, for which we propose the name

Festuca veneris.

hlorphological featiires of F. glauca, F. cinerea, F. inops and F. g ~ c i l i o rwere gathered from i i ~ v e s t i g ~ ~ t iori o i ~t!.pe s speciinens and other specimens housed in B O L O , FI: GDOR, PAV, R O , W L' aiid froni the original descriprions. Iiivestigations on lilants growind near Portovenere were carried out on specimens collected b! Soiiiniier in 1883 (FI, RO) kind by ourselves in spring 1995 (FI, PAV). W e adopted the follou,ing staildard methods and tcriiiinology, as already reported by FOGGI & ROSSI (1996): II,\irii& TL'CKER(1981) and BARTHLOTT (1990) for epidermal features (recorded under S . E . M . Philips XL3O). Kar!.ological observations were carried out on ovaries extracted from plants collected near Portovenere and grown in pots in the Botanica1 Garden of Florence "Giardino dei Seiiiplici". T l ~ eovaries, after a pre-treatment in a mixture of 8-hydroxyquinoline and alpha-Br-naphtalei~e (1:lì for 4 hours and fixation in 3: 1 ethanol-acetic acid and subsequentiy in 703 ethanol, were stnined with Schiff reagent. They were, then, put on a slide with one or two drops of acetic orcein, sq~iasliedand finally examined urider a light microscope ( 1 0 0 0 ~ ) . Autl-iors abbreviations are according ro BRURIMIT& POWELL(1992).

Festuca veneris G . Rossi, Foggi & Signorini, sp. nov. Differt ii Festuca glauca larninis minus pruinosis, tenuioribus, paniculis brevioribus, spicu];i!-iini pedicellis longioribus; a Festuca inopi laminis tenuioribus, vaginis haud meinbraneis. Ieinmatis arista longiore: a Festuca cinerea laminis tenuiorilus, rectis, Icmmate haud ciliato, ai-iiliriis brevioribus; a Festuca graciliore panicula breviore, lemmatis arista longiore; ab omnibus. ~ a g i n i sad superius dimidium clausis. 'Ti.iws - Holotypus: «Porto Venere (Liguria)/ Poggi aridi marittimi/ 30 5 1883 Hackel det.1 I i e r b S Somniier». ( F I , sub F. ovina var. glairca subvar. (nova) teizuioi.Ilackel!).

Plants densely tufted. Vegetative shoots intravaginal. Culms (15)18-20(25) cm. Leaves smooth, glabrous, slightly pruinose (maintained under cultivation). Leaf-sheaths greyish, overlapping, fused for 314 - 415 of their length, glabrous; auricles scarcely evident. Ligules very short (0.2-0.3 mm), minutely ciliate. Leaf-blades straight, fairly lank, (8)10-16(22) cm, acute, glabrous. Panicles very short, 3.5-4.5(5) cm, narrow, linear, rather dense, sometimes interrupted. Spikelets subpruinose, 6.5-7 mm, with 5-7 florets (plus one sterile floret); pedicels (0.8)1-Z(2.2) mm. Lower glume subulate, (2.5)3-3.4 mm, 1veined; upper glume (3.5)4-4.7 mm, 3-veined, with a broad scarious margin (112-113 of the laminar part), sometimes shortly acuminate. Lemma (4)4.5-5.2 mm (excl. awn), scabridulous on dista1 half, >-veined, always awned; awn 11.7(2)mm. Anthers (1.8)2-2.2(2.6)mm.

Lea thickni uous ri bullifoj Idea rodletwith ac sinuou cells: r~ larly dj Lea abund: rectani shaped

Ico

Leaf -biade anatomy : outline oval to V-ovai; diameter 0.47-0.55(0.6l ) mrn; thickness/diameter ratio 0.39-0.46; veins 5-7; sclerenchyma forming a continuous ring (1)2-3 cells thick; l(3) ridges on adaxial surface, scarcelv prorninent; bulliform cells always present. Leaf-blade adaxial epidermis (fig. 1). Epicuticular waxes: simpIe tetragonal rodlet-like crystalloids (figs. l a , l b ) . Stornata: 27-30 x 15-20 pm, solitary or with accompanying cork-cells. Long cells: rectangular, non-sinuous or slightly sinuous, abundant (frequency increasing toward the rnidrib). Interstomatal cells: rectangular, 70-90 p m Prickles: abundant, costal and intercostal, irregularly directed, 0.03-0.08 mrn (fig. Ic). Silica bodies: costal, crescent-shaped. Leaf-blade abaxial epiderrnis (fig. ld). Epicuticular waxes: few, except abundant along the rim. Stornata: absent. Long-cells: 70-180 x 15-30 bm, rectangular; width uniform; walls sinuous. Silica bodies: costal, crescentshaped. Hairs and/or prickles: absent.

ICONOGRAPHY - Fig. 2 (by A. Maury) PIIENOLOGY - Flowering: May-June.

Fig. 1 - Leaf blade n t S . E M Adaxial epidermis: a) epiciiticular uaxes; b) surface urith epicuticiilai \i.:iseh: ci surf.icc \ritliout epicuticiilai. waxes. Abaxial epidcrniis: d) \r~ithoutepiciiticular uases.

Fig. 2 - Fellrica ~.eiiei.is:whole plant ( X 0.8); spikelet ( x 8); lemma ( x 15); iippei- gliime l x 15): aritheisheachs ( x 1.5); portion of caulirie leaf with a ligula ( x 15); section of tiller leat L1,ides ( X 50). I2oc;ilities of sectioi-is: Portovenere, La Spezia. 6.5.1995, G . Rossi. I{\ Griitiliiji (PA!'); Por~oveiierc.1 . ~ Speziid. 4.6.1995, G . Rossi. M. Gri2tiliin (I'AV); Isola di Palniaria (La Spezia), 16.6.1995, B. Z'ogl

( x 15); leaf

p

O

-,p--

2

4

8

6

Km

Por t ovener e

I sola di Pal m a r i a =L Fig. 3 - Distribution area of l. cenrizs.

K 1 - The ~species was ~ found to~ be diploid, ~ with chromosome ~ ~ number 2n = 2 x = 14; voucher specimen: Portovenere, La Spezia, zona cave sotto Monte Muzzerone, stazione 1, alt. 230 m, esp. SW, substrato calcareo, rupi ~lerticalisul mare, 4.6.1993, G. Rossi, M. Gentilini (PAV). CIIOROLOGY AND ECOLOGY - F. veneuis is known from Portovenere and the island of Palniaria (fig. 3). I n this area the climate is mediterranean with a short dry period in julv ( C £ . FERRARINI, 1971; MARIOTTI,1990). It is t o be considered a local endemism of eastern Liguria; it shares the sarne area of distribution with Centnti~.enciize~a~in L. subsp. veneris (Sommier) Dostàl.

F. vene~isgrows on W-facing sub-vertical maritime cliffs exposed to windcarried salt spray, from about SO to 300 m a.s.1. I t occurs in crevices on liiriestorie rocks, where a shallow and poorly developed soil is present. This has been sampled in three sites at Muzzerone (Portovenere). Analysis of the samples revelled a sub-alkaline soil (pH 7.8), with a high total calcium carbon-

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26

G . ROSSI, B. FOGGI and M.A. SIGNORINI

TARLE 1 - Phytoso~iolo~ical t-elevés of phytocoenoses with

Relevè n. Elevation m Aspect Covered surface % Relevé area mq Substrate

Festr~cavntci.is

1

2

3

250

150 NW

1o

180 W 25

3o

25

W

20 2o

limestone limestone limestone

Mi 3( on ve] SOt

Sedum dasyphyllum L. Reichardia picroides (L,)Roth var. maritima Fiori Festuca veneris G.Rossi, Foggi & Signorini Centaurea cineraria L. subsp. veneris (Sornrnier) Dostal Thymus vulgaris L, Galium corrudifolium Vill. Helichrysum stoechas (L,) Moench Sesleria cfr. insularis Sommier Rhamnus alaternus L. Senecio bicolor (Willd.) Todaro subsp. cineraria (DC.) Chater Chritmum maritimum L. Euphorbia dendroides L. Piptatherum coerulescens (Desf.) Beauv. Phagnalon sordidum (L,) Reichenb. Teucrium flavum L. Fumana procumbens (Dunal) Gren. & Godron Dactylis glomerata L. subsp. hispanica (Roth) Nyman Daucus gingidium L.

ate content (37%), of which only a small percentage is in active form (4.7%) and with a high amount of organic matter (16%) and nitrogen (0,35 %). I n this habitat, F. veneuis grows associated with severa1 other plants, as shown by three phytosociological relevés (tab. l ) , al1 from the vicinity of abandoned limestone quarries: rel. 1, between the locality Martina and Muzzerone (near Portovenere), G . R . 4th June 1995; rel. 2, close to 1, G . R . 4th l u n e 1995; rel. 3, Island of Palmaria, between Punta del Pittoretto and Capo delllIsola, B.F. 16th June 1995. From a phytosociological point of view, this vegetation can be ascribed to the class Asplelzietea trichomanis Br.-B1. in Meier & Br.-B1. 1934 corr. Oberd. 1 9 7 i , as GÉIIU & BIONDI(1994) recently ~ o i n t e dout for the Corsica coasts. Moreover, this vegetation can be ascribed to the alliance Asplelzion petrarchae Br.-BI. & Meier 1934 and, probably, to the Cetztaurea veneris-comrnunity described bu MARIOTTI(1995) in the same area.

m:'

h11

;a' In E

del 1%

A NEW SPECIES OF FESTUCA L. F R O M LIGURIA (ITALY)

27

In the stations located at the lowest altitudes, the presence of species belonging to the class Crithmo maritimi-Limonietea pseudominuti Br. -B1. 1947 increases, due to the vicinity of the sea. Iso~ui~us: Porto Venere (Liguria), poggi aridi marittimi, 30.5.1883, Sonzmiei. (sub. F. ovit/a var. glr7r1cn subvar. (izova) tetzziioi. Hackel, RO) - PARATYI'I: Portovenere, La Spezia. Monte Muzzerone, rupi sul mare con Centaur-ea veneris, 270 m , esposizione 235O, inclinazione 90°, 3.6.1984, M. Tonzaselli (PARMA) - Portovenere, La Spezia, zona cave sotto Monte Muzzerone, oltre la Martina, sotto al Forte, stazione 1, alt. 230 m, esp. S W , substrato calcareo, rupi verticali sul mare, 6.5.1995, G . Rossi, M. Gentilini (PAV) - Portovenere, La Spezia, zona cave sotto Monte Muzzerone, stazione 1, alt. 230 m, esp. SW, substrato calcareo, rupi verticali sul 1n;ire. 4 6 , 1 9 9 5 , G . Rossi, M. Getttilini (PAV) - Portovenere, La Spezia, zona cave sotto Monte Muzzerone, presso la palestra di roccia, stazione 2, alt. 180 m, esp. SW, substrato calcareo, rupi 1,erticali sul mare, 4.6.1995, G. Rossi, M. Gentilini (PAV) - Portovenere, La Spezia. poco sotto la vetta di Monte Muzzerone, presso la palestra di roccia, substrato calcareo, rupi verticali sul rnnre, 4.6.1995, A. Balest~.elli(PAV) - Isola di Palmaria (La Spezia), presso le cave, fra Punta del Pittoretto e Capo dell'Isola, rupi su substrato calcareo, esp. NW. 16.6.1995, R. Foggi (FI) Isola di Palmaria, 16.6.1995, P.V. An-igoni (FI).

t

DISCUSSION - Some specimens of fescue collected at Portovenere in 1883 were probably sent by Sommier to Hackel. Hackel discusses the taxonomic value of this Festucn in a letter, sent to Levier on 24th of October 1910 and kept in the "Biblioteca di Botanica" librarv of the University of Florence; this letter very likely corresponds to the manuscript cited in the label of the specimens housed in FI and R O . For its name Hackel proposed Festuca ovina var. glauca subvar. tenuior and he describes the taxon as follows: "Festuca ovina var. glauca subvar. (nova) LP~ZLZO Hack., ~ differt a F. glauca typica laminis tenuioribus (diam. 0.5 - 0.6 mm), vaginis semiclausis ve1 omnino clausis". In the mentioned letter, he added these remarks: "Es ist diess eine sehr kritische Form ...(This is a very critica1 form, whose value can only be definitely ascertained through further investigations. Above all, it would be of great importance to know whether the leafsheaths of vegetative shoots are always closed as far as the rniddle or above. If so, then this form should be of higher value. Perhaps you could find them again by chance near Portovenere or in other nearby places)". This fescue has never been effectively ~ u b l i s h e d ,at this or other ranks, under F. ovrna var. glauca subvar. teizuzor or any other name. Festuca veneris is clearly distinct within the F. ovina aggr. Tab. 2 compares some characters of this species with those of F. glauca, F. inops, F. cinerea and E: graczlior. The species has a very restricted area of distribution and a well characterized ecologica1 behaviour. This is quite rare within the genus Festuca, and especially within the F. ovina aggr. I n fact, the only other species of this group

28

G.ROSSI,B. FOGGI and M.A.

SIGNORINI

Tn1ii.r. 2 - Distinctive characters separating F. veileris from F. giuuca. F. inops, F. c i i i e i ~ eaiid ~ T.gr,ocilioi 1: from AUQUIER & KEKGUÉLEN (1977) and KERGUÉLEN & PLONKA (1989);2: personal observations; 3: BEC:III & MIC:I:LI(1995); 4: K E R G U ~ L &EPLONKA N (1989).

Characters

F. veneris

F. glauca ( 1 )

F. inops ( 2 ) F. cinerea ( 2 ) F. gracilior ( 2 )

Leaf blade diameter (mm) Leaf sheat fusion Lower glume (mm) Upper glume (mm) Lemma (mm) Awn (rnm) Panicle (cm) Anthers (mm) Chromosome number

to grow on maritime cliffs are F. glauca, F. huonii Auquier and F. lahonderei Kerguélen & Plonka. F. huonii grows on the Atlantic coasts of Europe, where it is a character-species of the Festuco huonii-Platztagiizetum holostei Biaret et al. 1988 UULVE, 1993), an association of grassy slopes on maritime cliff tops along the southern and western coasts of the Brittany Peninsula. It has recently been reported (WILKINSON & STACE,1991) also for the coasts of Jersey and Guernsey (Channel Islands, Great Britain). F. lahonderei grows on the low coasts of Vendée ( N W France). 1977), curiously Like F. glauca in the Roussillon (AUQUIER& KERGUÉLEN, no botanists have published on this peculiar fescue in Liguria (PREDA,1903; BÉGUINOT,1907; FERRARINI, 197 1, 1972, 1988; MARCHETTI, 1985; MARIOTTI, 1985). DEL PRETEet al. (1985) and MARIOTTI(1990) reported F. circummediterranea Patzke, a quite different species of the F. halleri group (sensu PIGNATTI & MARKGRAF-DANNENBERG, 1982), for the Island of Palmaria.

Thanks are due to Prof. E. Nardi (Florence) for the critica1 revision of the text and of the latin diagnosis; to Prof. C A. Stace (Leicester, U.K.) for useful suggestions; ro Dr M. Bigazzi (Florence) for his assistance during SEM i n ~ e s t i ~ a t i o n to s ; Prof. F . Fabbri (Florence). Director of the Botanica1 Garden "Giardino dei Semplici", where some specimens were cultivated, also for his kind hospitality during our laboratory work.

A NEW SPECIES OF FESTUCA L. FROM LIGURIA (ITALY)

REFERENCES A u ~ c i e i iP . & KERGCELEN M . , 1977. - Uiz groupe embruuillé de Fertirca (Poaceae): les taxons désigités pai. l'épithète "glauca" eiz Europe occiderztale et dans les r.égions uoisines. Lejeunia n.s., 89: 1-82. B,\nliii.o.r-r W,. 1990. - S c a ~ z n i nclecti.oil ~ microscopy o/ the epideimal suijace i12 plaizts. In: CLAL'GHER D. (ed.), Scaiiiriiig Electroiz ~Microscopy in Taxoizomy aizd Fti1zctio11alMoipl~olop~'. 4 : 69-94, Claredon Press, Oxiord. UI:e Ieaf-blade as viet~.edzii trriiiverse sectiott. Bothalia 12 (1): 65-109. Fi:i