0 Acadbmie des sciences / Elsevier, Paris

Palaeontology / PalfZontologie (Palaeobotany / PalGobotanrque)

Surface Geosciences / Gosciences de surface (Palaeoenvironment / PalCoenvironnement)

New palaeontological discoveries in some Early Permian sequences of Sardinia. Biostratigraphic and palaeogeographic implications

Nouvelles dkouvertes pakontologiques dans quelques se’ries du Permien in.Gieur de Sardaigne. Sign@ation biostratigraphique et pal&o@ograpbique

Ausonio Ronchia, Jean Broutinb, jos&Bienvenido Diezbf”, Pierre Freytetb, Jean Galtierd, Francis Lethiers”

a Dipartimento delle Scienze della Terra, Universita di Pavia, via Ferrata 1, 27100 Pavia, Italy b Paleobotanique et paleoecologie, universite Pierre-et-Marie-Curie, 12, rue Cuvier 75005 Paris, France ’ Facultad Ciencias, Palaeontologia, Universidad de Zaragoza, 50007 Zaragoza, Spain ’ Universite Montpellier-II, Isem, Paleobotanique, Place Eugene-Bataillon, 34090 Montpellier cedex 02, France ’ Micropaleontologie, universite Pierre-et-Marie-Curie, tour 15, 4” &age, 4, place Jussieu, 75252 Paris cedex 05, France

Abstract-New palaeontological material was collected during recent extensive fieldwork in the Early Permian Perdasdefogu and Escalaplano basins (SE Sardinia). For the first time, an accurate biostratigraphic position can be assumed for the sediments of these two basins, on the basis of their fossiliferous content (floras; ostracods). Regional and inter-regional correla- tions are proposed and palaeogeographical implications are analysed. (0 Academic des sciences / Elsevier, Paris.)

Sardinia / Early Permian / palaeontology / biostratigraphy / palaeogeography

R&um6 - De nouvelles collectes paleontologiques or-it 36 realisees dans ies bassins Permien inferieur de Perdasdefogu et Escalaplano (Sud-Est de la Sardaigne), 2 l’occasion de rkents travaux de terrain intensifs. Pour la premiere fois, une position biostratigraphique prkise peut @tre proposee pour les formations de ces deux bassins, bake sur leur contenu palkontologique (flares, ostracodes). Des corr@lations regionales et inter+gionales sont propokes, et les implications palitogkographi- ques de ces nouvelles donnees sent analysks. (0 Academic des sciences / Elsevier, Paris.)

kwdaigne / Permien lnf&ieur / paleontologie / blostratigraphie / pal&ogkqrapbie

Version abr@$e (voir p. 717)

1. Introduction

At the end of the Late Hercynian orogeny, many small intramontane basins were formed in Sardinia, and filled up with various volcano-sedimentary deposits.

An undifferentiated ‘Permian-Carboniferous’ has been recorded for a long time in Sardinia, based on macrofloral

analysis (Arcangeli, 1901), revised and completed by No- varese (197 7), Comaschi Caria (1969). Some microfloral datings were proposed: Stephanian (Del Rio, 1973) for the San Ciorgio basin; Autunian (Barca et al., 1992) for the Guardia Pisano basin.

The numerous radiometric datings performed on the volcanic rocks from these ‘Permian-Carboniferous basins

Note present&e par Jean Dercourt. Note remise le 16 septembre 1998, accept& le 5 octobre 1998

C. R. Acad. Sci Paris. Sciences de la terre et des plan&es / Earth & Planetary Sciences 1998 327,713-719

A. Ronchi et al.

are rarely very informative, extending from 325 Ma to 140 Ma! An ignimbrite from Eastern Sardinia (Galtelli) gave 284 f 15 Ma (Cozzopoii et al., 1984).

Although the Autunian stage has already been charac- terised by macroflora at “Lu Caparoni” (Pecorini, 1962), as confirmed by our study, the south-east basins of Sardinia remain biostratigraphically ill defined. Our extensive col- lecting allows us to overcome this imprecision, particu- larly for the Perdasdefogu Basin (figure 7, A (4)). Recent preliminary work on amphibians and fresh water fish remains, performed in the Perdasdefogu Basin (Ronchi and Tintori, 1997), is in total agreement with the Autunian dating based on floristic data. We present here our new palaeontological studies, dealing with: - macroflora: the Perdasdefogu assemblage (impres- sions-compressions or permineralized structures coming from silicified horizons well located in the succession, mostly unknown up to now) and the Lu Caparoni palaeo- flora (impressions-compressions only); - microflora: extracted for the first time from these two basins; - algas and stromatolites: from Escalaplano and Perdas- defogu (first descriptions); - ostracods: from Perdasdefogu (first discoveries).

2. Geographical location

The studied basins are located in the northern part of Sardinia: Punta Lu Caparoni-Cala Viola (figure 1, A (l), B) and in the central south-eastern area of the island: Perdas- defogu (figure 1, A (4), C), Escalaplano (figure I, A (6), D).

3. Geological context

In the Lu Caparoni Basin (figure 1, B), the succession starts with some 15 m thick fluvial-lacustrine strata, lying unconformably on the Hercynian basement. These depos- its yielded a rich and diversified Autunian macrofloral complex (Pecorini, 1962; Casperi and Gelmini, 1980). They are unconformably overlain by a 250 m thick detritic succession (figure 1, B), the top of which is dated as Middle Triassic (Anisian) (P&au and Flaviani, 1982).

The Perdasdefogu Basin (figure 1, C) displays a 250-300 m thick succession with, from the metamorphic basement to the top: a basal conglomerate; a fossiliferous laminated lacustrine succession (argilite-siltite to sand- stone sediments) in which numerous intercalations of lavas, ignimbrites and very coarse (breccias) to thin volcano-sedimentary levels occur. This succession ends with peculiar carbonated beds (limestones and dolo- mites), black when silic:ified, varying in thickness from several metres to 70 m. Some pluricentimetric coaly hori- zons are intercalated in this carbonated series. The sedi- mentary succession is overlain by dacitic lava flows and rhyolithic bodies.

The small Escalaplano basin (figure 1, D) shows a great abundance of volcanic remains, associated with lacustrine-palustrine deposits. This 150-250 m thick

Figure 1. A. location of the main Carboniferous, Permian and Triassic basins in Sardinia. 1: Lu Caparoni-Cala Viola; 2: Gallura; 3: Seui-Seulo; 4: Perdasdefogu; 5: Monte Ferru; 6: Escalaplano; 7: Lago di Mulargia; 8: San Ciorgio; 9: Guardia Pisano; 10: Capo Teulada. Dashed: metamorphic Variscan basement and plutonic complex; white: Mesozoic and Cenozoic cover. B, C and D. Sections of Lu Caparoni, Perdasdefogu and Escalaplano basins. 1: undifferentiated volcanic rocks; 2: carbonate deposits; 3: lacustrine deposits (includ- ing volcanic t&s, cinerites); 4: fluviatile sediments (conglomerates, sandstones, pelites); 5: a) pedological nodules, b) anthracite layers. Fossils, o: ostracods; m: macrofloras; p: microfloras; s: stromato- lites; al: algae; a: amphibians; g: gasteropods; I: lamellibranchs; fs: silicified floras; f: fish remains.

* ,*~;: (‘i

A. Localisation des principaux bassins carboniferes, permiens et triasiques en Sardaigne. 1 : Lu CaparonXala Viola ; 2 : Callura ; 3 : Seui-Seulo ; 4 : Perdasdefogu ; 5 : Monte Ferru ; 6 : Escalaplano ; 7 : Lago di Mulargia ; 8 : San Giorgio ; 9 : Guardia Pisano ; 10 : Capo Teulada. Hachure : socle metamorphique varisque et complexe plu- tonique ; blanc : couverture mesozoTque et cenozo’ique. 8, C et D. Colonnes composites representatives des bassins de Lu Caparoni, Perdasdefogu et Escalaplano. 1 : roches volcaniques indifferenciees (laves, breches, ignimbrites) ; 2 : depots carbonates ; 3 : depots la- custres (incluant tuff et cinerites) ; 4 : sediments fluviatiles (conglo- merats, gres, pelites) ; 5 : a) nodules pedologiques, b) lits d’anthra- cite. Fossiles, o : ostracodes ; m : macroflores ; p : microflores ; s : stromatolites ; al : algues ; a : amphibiens ; g : gasteropodes ; I : lamellibranches ; fs : flores silicifiees ; f : restes de poissons.

volcano-sedimentary succession lies conformably on a 1-2 m to 15 m ‘basal conglomerate’, filling up a palaeoto- pography. Some horizons with ostracods (still unclassi- fied), gyrogonites and fresh water gasteropods are known (Pecorini, 1974).

4. Macroflora

Numerous fossil plants have been discovered by one of us (A.R.) in the black shales and siltites of the Perdasdefogu Basin: Asterophyllites longifolius; Annularia mucronata; A. sphenophylloides; Pecopteris elaverica; P polymor- pha; Callipteridium sp.; Neuropteris osmundae (= 0. du- fresnoyi); Odontopteris cf. lingulata (figure 2, 3); Taeniop- teris abnormis; Autunia conferta (figure 2, 6); Rhachiphyllum schenkii; Rhachiphyllum lyratifolia (fig- ure 2, 4); Dichophyllum flabellifera; 1 odevia nicklesii; Gracilopteris strigosa (figure 2, 5) Poacordaites sp.; Ernes-

C. R. Acad. Sci. Paris, Sciences de la terre et des plan&es / Earth & Planetary Sciences 1998.327.713-719

tiodendron filiciforme (figure 2, 2) ; Otovicia hypnoides; Walchia piniformis; Culmitzschia laxifolia; C. speciosa; Hermitia arnhardtii. This association, dominated by cal- lipterids and conifers, is similar to those recorded from the ‘Assise de Millery’ Formation, i.e. ‘Upper Autunian’ as- semblageof the Autun basin ‘stratotypic’ succession (Cha- teauneuf et al., 1992). At a regional level, in Sardinia, a correlation can be demonstrated, for the first time, be- tween Perdasdefogu fossiliferous strata and the tower sedi- tnentary beds of the Lu Caparoni series, the two floristic associations being, indeed, quite identical (figure 1, A (11, B, Cl.

ratialean ferns also represented by Stipitopteris rachises and Psaronius fragments of stem and root mantle. Other group of plants (ankyropterid and anachoropterid ferns, medullosan and cordaitean) are much less frequent. The preservation and accumulation of these silicified plant fragments are very similar to the plant assemblages de- scribed from the Stephanian of Grand-Croix or the Early Permian of Autun (Galtier and Phillips, 1985 ; Doubinger et al., 1995). The quantitative analysis showed a difference between these two localities with cordaites dominating the Grand-Croix vegetation whilst tree ferns and calamites dominated at Autun; this difference was interpreted irq terms of environment and ecology (Galtier and Phillips,

5. Microflora 1985). However it is certainly significant that the new assemblage from Sardinia seems dominated by tree ferns

A detailed sampling allowed us to extract well pre- served palynological assemblages from the Perdasdefogu and Lu Caparoni Basins. Except for the local peculiarities, these microfloras display the same qualitative and quanti- tative composition. Both are monosaccate pollen grains dominated, the Potonieisporites ‘novicus-bhradwajii’ complex being specially diversified and reaching some 50 % of the whole assemblage. 20 % of bisaccate grains are associated with typical ‘Autunian’ genera SUCII as Vittatina or Costapollenites. We identified the following groups and species: - spores: Convolutispora sp. 2, Peppers 1964 (figure 2, 7 0), Verrucosisporites spp., Laevigntosporites spp., Lunti- bladispora sp.; - pollen: Monosaccates: Potonieisporites novicus- Dhardwajii ~figgure 2, 12), Florinites diversilbrn;lis, F. medi- apudens, Florinites spp., Nuskoisporites cf. klausii; Non striate Bisaccates: Vesicaspora ovata, Gardenasporites /e- onardii, lllinites tectus, lllinites spp., Limitisporites spp.; striate Bisaccates: Protohaploxypinus samoilovichii (fig- ure 2, 11 1, Protohaploxypinus sp., Hamiapollenifes sp.,

Striatoabieites sp.; Plicates: Viftatina ova/is (figure 2, 9), Vittatina sp., Costapollenites sp.; such an assemblage is consistent with the A3 biozone defined by Doubinger (1974) for the Western Europe Autunian biozonation.

and calamites like the nearly contemporaneous silicified vegetation from Autun.

7. Oolites, algas and stromatolites

6. Permineralized plants

Their occurrence was unknown in Sardinia. Larustrine pelites of the Escalaplano basin (l-2 m thick) locally con- tain pluridecimetric, more or less rounded, large masses corresponding to the accumulation of small millimetric algal colonies. These colonies are organised either as bunches of erect and ramified very close filaments, pluri- lobated in transverse section, (Toutinella sardiniana Freytet, 1997 (figure2, 8), or as round-elliptic, actually independent, bodies of radiating filaments (Toufinell~ r+ didta Freyiet, 1997 (figure 2, 7).

Thinly laminated stromatolitic cupolas (diameter: 1.5-20 cm) have been recorded in some stones of an enclosing wall, near the abandoned anthracite mine (‘Rio SLI Luda’ locality, Perdasdefogu). Dolomitic blocks, ob- served again in enclosing walls, contain more or less deformed millimetric oncolites (‘Nuraghe San Pietro lo- cality, Perdasdefogu) or joined fibro-radiating oncolites (diameter: 0.3-0.4 mm), deformed at the contact points (‘San Salvatore’ locality, Escalaplano).

8. Ostracods from Perdasdefogu

Three continental species have been recorded. - Candona n. sp., cf. planidorsata Cooper, 1964 llfigure 3,

These plants, preserved as siliceous permineralizations, 3, 4, 5) is abundant at various levels. On the black shales occur in angular cherts (‘fs’, figure I, C). Generally, the split surfaces, isolated valvas (up to 25 per cm’), appear specimens contain a number of different small plant frag- brown coloured by iron oxide. In the black silicified ments suggestive of plant accumulation in coal balls (fig- horizons, the entire undeformed shells appear white ure 2, 1). More rarely, one specimen may consist of a standing out, due to their siliceous epigeny. The ICandona single plant fragment, for example of a calamitaean or a genus is questionable here because the adductor muscle cordaitalean woody stem. The plant assemblage consists imprint being yet unknown, the attribution to the Ceno- oi: Sphenophyllum, Arthropitys, Astrom ye/on, Calamo- zoic genus Candona Baird, 1845 remains hypothetic:al. stachys, fecopteris, Scolecopteris (figure 2, I), Stipitoperis The larva incubation by the female is evidenced for the (ST, figure 2, I), Psaronius, Anachoropteris, Ankyropferis, first time in this group, as early as the Permian, through the probable medullosan wood and ovules, Cordaites leaves observation of in situ larvas (figure 3, 5). This new species and cordaitalean wood. The most common elements: occurs also in the upper part of the ‘Buxieres’ Formation Peropteris and Scolecopteris correspond to the vegetative (northern French Massif Central), i.e. Late-Early Autunian and fertil leaves of probably two different species of mar- in age (Damotte et al., 1992);

C. R. Acad Sci. Paris, Sciences de la terre et des plan&es / Earth & Plunefary Sciences 1998 327.713-719

715

New Daiaeontological discoveries in some Early Permian sequences of Sardinia

A. Ronchi et al,

- Palaeodarwinula sp. (figure 3, 6, 7) is a rare species, the bad preservation of which permits only a comparison, without biostratigraphic value, with 19 elegantella Be- loussova, 1963, from the Early Tatarian of the Russian

platform. The Palaeodarwinula genus Molostovskaya, 1990 is highly diversified worldwide in the Latest Carbon- iferous and Permian continental domain.

Figure 2. 1. Permineralized plants from the Perdasdefogu Basin: fertile pinnules of Scolecopterisand probable parent frond rachis Stipitopteris:

‘ST’ (sample SAR 02 C 502; bar: 1 mm). 2-6. Sterile foliage (compressions): Perdasdefogu Basin. 2: Ernestiodendron fificiforme (sample P.20); 3: Odontopteris cf. lingulat;~ (sample P.98.1); 4: R. lyratifolia (sample P.115.1); 5: Gradopteris sfrigosa (sample P.l15.4); 6: Aufunia conferta

(sample P.21.3b). 2-6: (bar: 5 mm; 2; 4-6: same scale). 7,8. Algae (Escalaplano basin). 7: Toufineh radiata Freytet, 1997.8: Toutinella sardiniana

Freytet, 1997 (bar: 250 pm). 9-l 2: Palynomorphs. 9: Vittafina ova/is Klaus; 10: Convohtipsora sp. 2 Peppers, 1964; 11: f’rotohaploxypinus samoilovichii (Jansonius) Hart; 12: Potonieisporites novicus Bhardwaj. (bar: 9, 10: 5 pm; 11 ,12: 10 pm).

1, Plantes permin~ralisees du bassin de Perdasdefogu : pinnules fertiles de Scolecopteris et son probable rachis porteur Stipifopferis : N ST ,) (kh.

SAR 02 C 502 ; barrr : 1 mm). 2-6. Feuillages steriles (compressions) : bassin de Perdasdefogu. 2 : Ernestiodendron filkiforme (khantillon P.20) ; 3 : Odontopteris cf. /ingu/a!a (khantillon P.9H.l ) ; 4 : R. lyratifolia kkhantillon P.115. I) ; 5 : Gracibpteris strigosa (kchantillon P.ll.5.4) ; 6 :

Autmia conferta (bchantillon P.21.3b). 2-6 : (Barres : 5 mm ; 2 ; 4.-6 : mtme khelle). 7, 8. Algues (bassin d’tkalaplano). 7 : Toutinella rrldi.lt‘J

Freytet, 1 YY7 ; 8 : TocGinella ~ardiniana Freytet, 1997 (barre : 2.50 I’m). 9-12 : palynomorphes. 9 : Vittatina owlis Klaus ; 10 : Convolutipsora sp. 2 Peppers, 1 Y64 ; 11 : Profohap/oxypinus samoilovichii (Jansonius) Hart ; 12 : Potonieisporites novicus Khardwaj. (bares : 9, 10 : 5 11m ; 1 I, 12 :

10 IrmJ.

716 C. R. Acad. Sci. Paris, Sciences de la terre et des plan&es / Earth & Planetary Sciences 1998.327.713-719

New palaeontological discoveries in some Early Permian sequences of Sardinia

Figure 3. Ost I from Perdasdcfogu. P6M = collection number, ostracods. University Paris-Vi, Micropalaeontology. bars: 0.20 mm. 1,2: WhippleUa carbonaria Scott, 1994.1: dorsal view, P6M 1977. 2: left lateral view, P6M 1974. 3-5: “Candona” n.sp., cf. planidor- sata Cooper, 1946. 3: left lateral view, P6M 1980. 4: dorsal view, PAM 1978. 5: left lateral view showings five instars inside, P6M 2036.6, 7: Palaeodarwinula sp. 6: dorsal view, P6M 1975. 7: right lateral view, P6M 1976.

Ostracodes de Perdasdefogu. P6M : numeros de la collection ostra- codes, universite Paris-VI, micropali?ontologie. Barres : 0,20 mm. 1, 2 : Whipplclla carbonaria Scott, 1994. 1 : vue dorsale, P6M 1977. 2 : vue latt!rale gauche, P6M 1974. 3-5 : N Can~kxta x nsp. , cf.

planidorsata Cooper, 1946. 3 : vuc latktle gauche, P6M 1980. 4 :

vue dorsale, P6M 1978. 5 : vue laterale gauche monlrant tiny Iarveh

6 I’intbrieur, P6M 2036. 6, 7 : Palaeodarwinula sp. 6 : vue dorsale,

P6M 1075. 7 : vue latkrale droite, P6M 1976.

- Whipplella carbonaria Scott, 1994 (figure 3, 1,2) shows a wide geographical distribution (Lethiers and Damotte, 1993): USA, Morocco, France. It occurs first in the Latest Carboniferous of Illinois, swarms in the Autunian of France and persists until the late Early Permian in Mo- rocco. Finally, taking into account our knowledge of the first and third species, we can propose an Autunian age for the Perdasdefogu ostracod horizons and, more precisely, ‘Middle’ Autunian.

The palaeoecoiogical implications, deduced from the analysis of this small association, recall strongly those evidenced for the Noyant-Souvigny Basin (Damotte et al., 1992). We deal with a fresh water or weakly oligohaline permanent iacustrine environment, even if lower during less humid periods.

9. Biostratigraphic and palaeogeographic implications

At a regional level, in Sardinia, a correlation can, for the first time, be demonstrated between Perdasdefogu fossilif- erous strata and the lower sedimentary beds of the Lu Caparoni succession, the two floristic associations being, indeed, quite identical (figure 7, A (I), B, C).

The present palaeontological data suggest a Middle Autunian date for the Perdasdefogu volcano-sedimentary succession which corresponds precisely to the ‘Surmoulin’/‘Millery’ Formations of the Autun basin (Cha- teauneuf et al., 1992). The comparative analysis of the fossiliferous silicified horizons, well located in the Perdas- defogu stratigraphic succession (figure I, C) and the silici- fied pebbles with fossil plants, dispersed in the Autun basin, points out that the last ones are actually Autunian in age and do not result from the reworking of underlying Stephanian beds. In this respect, the Perdasdefogu Basin does represent a reference succession for this Early Per- mian period, in the whole westernmost palaeo-tethyan domain.

From a palaeogeographic point of view, it is significant that a palaeoflora very similar to the one of Perdasdefogu has been recorded from identical black shales of the Gerri de la Sal succession, Catalan Spanish Pyrenees (Gisbert, 1983). Thesedata are in full agreement with the palaeopo- sition proposed for the Corsica-Sardinia ‘block’ by Broutin et al. (1994, fig. 12) in a palaeogeographical reconstruc- tion based on structural and magmatism data. In such a model, this ‘block’ is elongated east-west, so that the southern part of Sardinia is linked with the southern Pyre- nean domain.

Version abr&gee

Introduction Nous prkentons ici nos olwrvtltions pal~ontologic~ues sur : - les macroflores de I) Perdasdefogu (pour la plup~~rt incon- nues jusqu‘alors : empreintes et structures perminCralis&s provenzmt d’horizons silicifi$s bien c&s dans la &IX) ; 2) 1,~ Caparoni lempreintes exclusivemcnti : - les microflores de ces deux hassins (premiPrc analyst) : - les algues et stromatolites 5 Escalaplano et l’erdasdefogu ; - Iv:, Ostracodes :I Pertiastiefogu ( prwiikcs d6couwtes 1.

Localisation geographique

Les basins permirns Ptudib soni localis@s au nerd : I’unta 1.u Cq’;~rom Cala Viola (,fi,qwc 7, A ( I ). 131 ; ;1u Centrt: sud-est : I’erdascle~ogu (~/~~rw 7. A (4). C). I:acalapl3no cjigwc 1, A (6), II)

C. R. Acad Sci. Paris, Sciences de la terre et des plandtes / Earth & Planetary Soences 1998.327,713-719

717

pinus sp.% I;rcnnaiup~ll~~~7itt~s sp., Striatoabieites sp. ; Plicates :

l’ittatirla 0lali.s cfigure 2, 9), Wttatina sp., CmtupoZlenites

sp. C’est un assemblage t&s comparable 1 celui d&it pour 1~ biozone A:j, dPfinie pour I’Autunien d’Europe occidentale par

I)oubinger ( 1974).

Vi+gi%aux permin&alis&

Ces @antes fossiles sont silicifi2es dans des chej7.s anguleux

ifs, Jigz~ I, C). En g&-Gml, cm olxerve me accumulation de

pebits debris c~g~taux. comme dans les coal balls Cjgure 2, 1).

1~1~1s rarement, tin spkimeri peut ne renfermer qu’un fmginent

de plante, par exemple : tigc dc C&mites ou de Cordaites. Ont

et6 ident ifi& : Spbenopb)tllnr m. .&lbropi[~~.s, Asf rnrn~~&r z, Cd.+

ttzostacb~vs, Pecopteris, S~oleco~plwis (/&m 2, 1 ), St@itqwi.s

( S’I’. j&w 2. 1 ), Psaro?7i?fs. A7m~boroptwi.s, An&t-optcv~s, his

e1 ov11les p&win& de iWdullosales. feuilles et hois de Cbr-

&&es. Lvs kltments Itbs plus communs, P~o,btcKY et Sctkw~)-

wis correspondent :NS feuilles vi-g&atives et fertilcs tic M:ir-

ratides. Modes de prkwrvation et d’accuinulation sont trL:s

similaires :i ceux dex associations silicifiks dkriws clans le

Wphanien de Grancl’Crois (hassin de Saint-Etienne) (xi le

I’crmien infkieur cl’Aut tin (Gait ier et Phillips. 1085 : Doubin~ei

et al.. 1095 1. II est signific2tifquc I’asscmhlage de Sardaigne soit

domin6 par It3 fougPres arhoresccntes ct les Calamites, comne

c‘t-al le c‘;is pour la flora Glicifi& autunit~nnr du bassin d’A1itun.

Oolithes, algues et stromatolithes

Leur pksence &it inconnue en Sartlaigne. Des pi>litcs

I;ic~istres tl1i Ilahsin ti’lk;ilapl;ino renfermcnt des r~olonies

algaire\ miliim~triclues regroup&s en masses plurid~cim~tri-

qua. fw-iiiCw wit tie twuquets tie filaments tiressPs. r:unifiCs.

tassi’s. i sections tnrnxwrs2les plurilol~~es ( ~Tf~zrtitrclkr sclrrli-

trirrtw FreyttY. 10~7,,/i~rm ) 2, 8). soit de corps xrontlis ellipti-

ques li fil;iments rayonnants I'lhrtiwkr rdiato Frqwt. I$W,

,fi,ym 2, 7).

k lbdastlefogu. ties co11polc’s slroii~itoliticl1ics de 15 :1

LO cm tie tliam~tre. S tr& fines laminations. on1 W ohservki

dans tine niurctte prh d’une mcicnnc mine tl’antfmcite. I )cs

blocs dv doloinie. pro\wi:inl ~#;lleiwnt clv inuretks. renter-

mvnt cles oncolit~s m~llim~tricl1ies, tl~lormks au ~~mact les

me5 cks autrcs.

Ostracodes de Perdasdefogu

‘l‘rois espPces conlint~ntales sont ri’pertorikes. - Ca~dot~u n.sp.. cf. Pkri~irlowrl~~ Cooper, I%6 (,figuw .I. 3. -t.

5) ahond~ dans certains nivcaux. Les surfaces clklit&s de

SlUles noirs niontrent jusqu’9 25 ~dves isolCes par ccntim&re

carr6. et tics carapaces compl&es. Ix genre C,i87t7!077u demeure

ici incertain. car I’empreinte du muscle adducteur n’fklnt pas

encore conntle. l’attrihution au genre cknoztiiclue C’rr77~lorzrr

Baird. lZ-25 restc liypotli~tique. L’inculxition des lakes p:1-r lcs

femelles est &3iiontr&2 pour la premik fois tlans ce groupc~,

(Ii‘s le I’crmien. gr:ice ci I’ohservalion de lar\w silicifi&s in situ

(,Jig’rltv .i. 5). Cette nouvelle es~i:ce existe Lyylement cI;I~ la

partic supi-rieure de la forination ck Huxii-res (somt~~~t &

I‘Autunien inkkieur, Massif central franyais : I)amotte et :~l..

IWLI.

718 C. R. Acad. Sci, Paris. Sciences de la terre et des plarktes / Earth & Planetary Sciences 1998.327.713-719

New palaeontological discoveries in some Early Permian sequences Iof Sardinia

Acknowledgements. The authors wish to thank Prof. G. Cassinis. Prof. P. Pittau. Prof. Del Rio, Prof. G. Oggiano and Dr. Filigheddu for helpful discussions. The research was supported by Murst (40 %) and Consiglio Nazionale delle Ricerche (CNR) grants. IPubl. ISEM no 98-106

10. References

Arcangeir G. 1001. Contriburione allo studio dei vegetali per- Imo-carboniferi della Sardegna, P,l/,leontogr,iphiaa It., 7, 91-1 20

Barca S., Del Rio M. and Pittau Demeiia P. 1092. Lithostratigraphy

and microfloristic analysis of the iluvial--lxustrine Autunix basin in

the Sulcis area (Southwestern Sardinia, Italy), in: Carmignani L. amI

Sassi F.P. it&.), IGCP 276, Nnvsktte~; vol. 5f, $,pet. issue, Siena,

45-4’)

Broutin I., Cabanis K., Chateauneui I.-J. and Deroin J.-P. 1994. ivolution bisotratigraphique, magmatique et tectoniclue du domaine

paleot@thysien occidental (Sud-Ouest de I’Europca) : implications pa-

lkgkgraphiques au Permkn inftrieur, &I//. Sot. gPo/. Franc-cx, 16.5,

2, 16 i--l 7’1

ChaleauneufJ.-J., Farjanel G., Pacaud C;. and Broutin J. 1992. The Autun Permian Basin, the Autunian stratotype, C,~hiers Micropa/.,

N.S., 7, l/L, 107&121

Comas& Caria I. 1959. Le piante fossili della Sardegna, Mem.

Riv. II. P,t/. Strut., 7, 176 11.

Cozzupoli II)., Discendenti A., Lombardi G. and Nicoletti M.

1971. Cronologia K-Ar delle tmniiestazioni erultivr &I settore (Ii

Seui-Seulo (Barbagia, Sardegna), Period. Miner~I., 40, 11 3-l 24

Damott? R., Lethiers F., Corbin C., Renard M. and Debriette t?

1992. Premi+res donnees sur la faune d’ostracodes du Permien in-

ferieur de Souvigny tNortl du Massii central, France), Rev. Mirrm

palaeont., 35. 4, 2.33-270

Damotte R., Durand M. and Lethiers F. 1996. Dkouverte cl’une

faune d’obtracodes dans la Formation d’A.lbfi (Permien basal des Vosges), C;Go/ogie de /a Frdncr, 2, 82-87

Del Rio M. 1973. Palinologia di un livello Permo-Carbonifero cle

bat ino di San Gorgitr Ilglrsientc~. Sardegna sud-occiriental~,), Ho//. Sot. Geol. II., 92, 48.5-494

Doubirrger J. 1974. etudes palynologiques dans I’Autunkn. Krv.

P,7/aeobot. P~lynol., 1 7, 2 l--30

Doubinger J., Vetter I?, ILangiaux J., Galtier J. et Broutin J. 1085. 1 a flow du bxkn houillcr dr Saint-itrcnne, M&n. MIIS. mtn. Hist. n,~t., 1, 1.. ii7

Francavilla F., Cassinis C., Cocorra T., Gandin A., Gasperi C;., Geln?ini R., Rau A., Tongiorgi M. ano Vai G.B. 1977. Macroflora e

datazionr d alcuni affioramenti (tardo)-postercinici presso it Ldgo di

Mularfiia (Sardegna sud-orientale), Roll. Gruppo di Lworcr sd

P,l/‘Eoroico, 2, 31-33

Freytel I? 1997. Non marine Permian to Holocene algae from France and adjacent countries, Ann. falaeont., Masson, Paris, 83, 4,

28’1~-132

Galtier J. and Phillips -r.L. 1985. Swamp vegetation from

Grand’Croix (Stephanian) and Autun (Autunian), France and corn- parisons with Coal Ball Peats of Illinois Basin, in: C.R. 9” Congr. ht.

Stat. Go/. Carbonifkre, Urbana, USA, 5, 13-24

Casperi G. a~~tl Geimini R. 1980. Ricer&e sul Verucano. 4. II Verrucano della Nurra (Sardegna nortl-occidentdli‘), /\/lem. Sot.

Geoi. II., 20, I970. 21 5--231

Cisbert J. 1983. El Permko de /OS I’irineos EspaAoles, in: Cdwn- ito. y Permir 0 de Espdhl, Y’ Congo: Intern. Strat. G&I/. Cxh,,

Madriti 1983, ICME, 4055420

Lethiers F. and Damotte R. 1993. La grande dispersion des espkxs

d’ostracodes i(:rustatea) d’eau deuce 2 la fin de I’ke primaire, C. R.

AC&. Sri. /‘arib, 31 6, Series II, 427-431

kthiers F., Damotte Rand Whatley K. 1097. Evidence of brooding

in Permian nor-marine Ostracoda, klhaia, 29, 21 Y-223

Novarese V. 1 Y17. L’Autunlano in Sardegna, Boll. Sot. Geol. Ita/.,

Roma, 36

Pecorini G. 1062. Nuove osservazioni sul Perrmco clella Nurra

(Sartlegna nord occidentalc), Atfi Ace. Nor. incej, Rend. CI. fis. mat. e

nat., ser. 8, 32, 377-300

Pittau-Demelia P. and Flaviani A. 19B2. Aspects of the palynos- tratigraphy of the Triassic Sardinia srcluences (preliminary report),

Rev. P;il;whot. P,7/yno/.. 37, 329-I343

Konchi Aand Tintori A. 1997. First Amphibian find in Early Per- mialn from Sardinia (Italy), Kiv. il. I%/ac~~nt. Sfrat., 103, 1, ;!O-‘38

C. R. Acad. Sci Paris, Sciences de la terre et des planittes / Earth & Pianefary Sciences 1998 327, 713-719

719