New insights on the Permian and Triassic vertebrates from the Iberian Peninsula with emphasis on the Pyrenean and Catalonian basins

Few studies paid attention to the Permian and Triassic vertebrates from the Iberian Peninsula and a re-evaluation of these faunas is needed in order to compare them with other European basins. As a first step, we present here the available data from the Catalonian and Pyrenean basins (NE of the Iberian Peninsula), offering new insights on the diversity and temporal distribution of their vertebrate faunas. The two basins have yielded unexpectedly abundant and diverse vertebrate assemblages, including fishes, amphibians and reptiles from continental and marine environments. The revision of classical finds and the analysis of new material provide data towards an understanding of the evolutionary and palaebiogeographical history of the Permian and Triassic vertebrate Iberian faunas. Permian remains mainly correspond to footprints recovered from alluvial deposits; the osteological record is scarce in the Iberian Peninsula. Early Triassic vertebrate localities are unknown. Middle Triassic faunas are abundant and reflect the change from continental environments to a wide diversity of coastal and marine depositional environments. During the Anisian, faunas are represented by footprints and skeletal remains of amphibians (capitosaurs) and terrestrial reptiles (archosauromorphs and procolophonoids). Ichthyofauna, sauropterygians, thalattosaurs and protorosaurians are known through the late Anisian and Ladinian. Finally, Late Triassic localities representing coastal environments have also yielded marine reptiles (sauropterygians) and a diverse ichthyofauna.


Introduction
Permian and Triassic vertebrate assemblages from the Iberian Peninsula are poorly known.Permian vertebrates are only represented by footprints from the Pyrenees and the Cantabrian mountains (Robles and Llompart, 1987;Gand et al., 1997;Demathieu et al., 2008;Fortuny et al., 2010), and skeletal remains are only known from the Balearic Islands (Pretus and Obrador, 1987).
Triassic vertebrate assemblages are mostly represented by marine taxa (Sanz et al., 1993).The non-marine Triassic units have been rarely reported as containing vertebrate skeletal evidence (Gaete et al., 1993;Knoll et al., 2004;Witzmann and Gassner, 2008), thus little search for vertebrate remains was undertaken in the Permian -Triassic rocks of continental origin in the Iberian Peninsula.The most studied vertebrate-bearing Triassic localities in the northeastern part of the Iberian Peninsula are the marine deposits of Alcover sites (Tarragona Province, Catalonia, Spain), dated as late Ladinian (Calvet et al., 1987;Calvet and Tucker, 1995).However, several other vertebrate-bearing sites occur in both Buntsandstein and Muschelkalk facies.Those sites yielded bones and teeth of fishes, amphibians and reptiles as well as tetrapod footprints.
The present study focuses on the Permian and Triassic vertebrate remains recovered in the Pyrenean and Catalonian basins (North Eastern Iberian Peninsula).New vertebrate occurrences as well as new vertebrate localities (Fig. 1) are reported here.The previously known vertebrate remains and localities are reviewed and re-evaluated.We discuss the results obtained from the analyses of the faunal composition of classical and new vertebrate localities from the Iberian Peninsula in a palaeobiogeographical context.

Terminology used
Here we refer to a domain as a particular sub-basin with a specific sedimentary history and with imprecize paleogeographic boundaries.

Geological and palaeogeographical setting
The Permo-Triassic rocks of the Iberian Peninsula are usually broadly subdivided into the classic Germanic facies: Buntsandstein, Muschelkalk and Keuper.These facies are not considered time intervals, as the development of the different rift systems in central and western Europe was not coeval, causing diachronous facies changes (López-Gómez et al., 2002 and references therein).
The vertebrate remains of this study come from the Pyrenean and Catalonian basins (Fig. 2).The latter was isolated from the rest of the Iberian Peninsula during Late Permian times.During the Early Triassic, its southwestern corner was connected to other Iberian basins evolving in a half graben with differentiated depo-evolving in a half graben with differentiated depo-in a half graben with differentiated depo-in a half graben with differentiated depo-differentiated depositional environments (Calvet and Marzo, 1994).As a consequence, the local Permian and Triassic sedimen-Permian and Triassic sedimentary record is highly variable (Vargas et al., 2009).

Results on the Permian and Triassic vertebrate localities
New and classical vertebrate-bearing localities from the above-mentioned basins are listed and briefly described below.Previously published information about the sites is revised, and new specimens are described (Figs. 1,2).

Permian
All the vertebrate remains were recovered in the Buntsandstein facies from the Pyrenean basin.This facies are characterized by red fluvio-lacustrine sediments.Unfortunately, Early Triassic fossils are lacking between the common "Thuringian" and Anisian assemblages due to the presence of a stratigraphic hiatus and/or the exis-the existence of arid environments that prevented optimal conditions for life and fossil preservation, causing difficulties with the age determination of the Early Triassic deposits.Regionally, the identification of the Permian -Triassic Boundary (PTB) is difficult (Díez et al., 2005;Bourquin et al., 2007).
Ribera d'Urgellet area (Lleida Province), Pyrenean basin: Two large ichnofossils from the Permian locality of Palanca de Noves were described and referred tentatively to labyrinthodonts or cotylosaurs and to chirotheriid reptile trackmakers (Robles and Llompart, 1987).Recently, new footprints belonging to at least four different ichnotaxa were discovered in similar levels, all of them included in the sandstone and mudstone unit (Fortuny et al., 2010, for further details).From a geological point of view, two stratigraphic units are present in this area, separated by an angular unconformity between them; the lower unit yielded tetrapod footprints and was dated as Late Permian by Robles and Llompart (1987).Palynological analysis allowed the assignation of this unit to the Thuringian (Broutin et al., 1988;Calvet et al., 1993).
Nevertheless, the term Thuringian is no longer accepted as a chronostratigraphical unit (Díez et al., 2005) and further work is needed to determine its age.
In the CCR, the Muschelkalk facies are represented by two carbonate units separated by a mudstone-evaporite unit.The lower carbonate unit presents an "evaporiticsilty-sandy-complex" that gradually changes into limestone at the base of the section in the Catalonian basin.The upper boundary is marked by the sharp passage to the overlying siliciclastic-evaporitic deposits of the mudstone-evaporite unit (middle Muschelkalk) (Calvet and Marzo, 1994;López-Gómez et al., 2002).Two vertebrate localities are known from the lower carbonate unit (see below).On the contrary, no vertebrate fossils have been discovered in the mudstone-evaporite unit (middle Muschelkalk), composed of siliciclastic-evaporitic de-iliciclastic-evaporitic deposits in gradual vertical transition to the upper carbonate unit.The upper carbonate unit (upper Muschelkalk) can be divided into three domains: Baix Ebre -Priorat, Gaià-Montseny and Prades (Calvet et al., 1987;Calvet and Marzo, 1994) 2).The Prades domain is the most interesting from a palaeontological viewpoint.It is divided into five units: the Rojals, the Benifallet, the Riba, the Alcover and the Capafons units (Calvet et al., 1987;Calvet and Tucker, 1995).Two vertebrate-bearing outcrops are reported from the Alcover unit.
From the Pyrenean basin, only two vertebrate-bearing localities are known.Both are from the upper Muschelkalk and subdivided into three informal units: Marly Dolomites unit, Grey Limestone unit and Laminate Limestone unit.Vertebrate localities occur in the Laminate Limestone unit, corresponding to the transition to the Keuper facies (Calvet et al., 1993;Calvet, 1996).
Cervelló area (Barcelona Province), Catalonian basin: The ichnospecies Chirotherium catalaunicum was described by Casanovas-Cladellas et al. (1979) from the Can Paulet locality.The ichnospecies was based on a single tetradactyl footprint, 16 cm long and 12 cm wide.Unfortunately, the holotype specimen is now lost.Chirotherium catalaunicum is considered here to be a nomen dubium because it lacked diagnostic features, as previously reported (Casanovas-Cladellas et al., 1979).On the other hand, fragmentary bones (IPS-44010) with typical temnospondyl sculputure were collected in a nearby quarry (Cantera de Turó Roig locality), in a probable similar stratigraphic position.All the remains are included in the Sandstones and Mudstones of the Aragall unit (upper part of the Garraf domain) from the Bundsandstein facies.The siliclastic sediments of the Garraf domain are dated as Anisian by palynomorphs (Solé de Porta et al., 1987;Calvet and Marzo, 1994) and char-acterized by the presence of shales at the base and conglomerates and sandstones in its upper part.It shows changes in thickness of the sedimentary unit along the basin, as it also happens in the Montseny-Llobregat basin (Calvet and Marzo, 1994).
Riera de Sant Jaume sites (Barcelona Province), Catalonian basin: A partial hemimandible containing the postglenoid region and exposed in labial view (Fig. 3) was recovered in the Sandstones and Mudstones of the Figaró unit (Montseny-Llobregat domain).The silici- The siliciclastic sediments deposited in the Montseny-Llobregat domain originated from the erosion of the Iberian Massif and were distributed unequally in the sub-basin.They are mainly composed of sandstones, mudstones and red clays, and locally of conglomerates and breccias (Marzo, 1980;Calvet and Marzo, 1994).The age determination of the Montseny-Llobregat domain by palynomorphs revealed an Anisian age for the major part of siliclastic sediments of the domain (Solé de Porta, 1987;Calvet and Marzo, 1994;Dinarès-Turell et al., 2005), although magnetostratigraphic work in the lower part of the Riera de Sant Jaume section revealed the presence of the Lower Triassic (Olenekian) (Dinarès-Turell et al., 2005).The specimen was recovered in the upper part of the Riera de Sant Jaume section and the site is considered Anisian in age.This specimen had never been described despite the fact that it represents the third occurrence of a capitosaurian temnospondyl in the Iberian Peninsula (Gaete et al., 1993(Gaete et al., , 1996;;Witzmann and Gassner, 2008).The incomplete mandible MGSB-39.483 (Fig. 3) is 27.3 cm long.It is contained in a hard sandstone matrix and exposed in labial, dorsal and posterior views.Most of the posterior half part of a right hemimandible is pre- served, including the postglenoid area (PGA), the major part of the angular and a small portion of the postsplenial, and the dentary lacking the anterior part.Teeth are not preserved.
The PGA is well developed and contains the surangular and the articular.The surangular occupies most of the posterodorsal part.The articular is only present in the posteriormost part of the PGA, occupying the marginal border.The posterior part of the PGA shows a slight outgrowth.Only the hamate process of the prearticular is visible, being distinct, well developed and high.The angular shows a marked ornamentation, less evident in the anterior part, and it does not participate in the PGA.The mandibular sulcus is the principal sensory canal, while the accessory and oral sulci are weakly developed.Unfortunately, the presence or absence of a chorda tympanic foramen cannot be assessed with confidence.The calculation of the profile value of the PGA (Jupp and Warren, 1986) is negative, while the glenoid fossa appears to be at the same level as the dentary.This, added to the presence of a distinct, high and well-developed hamate process of the prearticular, lead us to assign the specimen to the capitosaur group.In their review of the lower jaws of capitosaurs, Maryánska and Shishkin (1996) sort out them into four types, mainly based upon the diagnostic characters present in the PGA.The hemimandible here described corresponds to type IV, characterized by an elongated PGA and a depressed dorsal surface.This type is found in capitosaurs such as Eryosuchus and Mastodonsaurus and it occurs also in the capitosaur mandibles recovered in the Montseny area, recently assigned to the new taxon Calmasuchus acri (see below; Gaete et al., 1993, Fortuny et al., in press).A reliable generic attribution of MGSB-39.483 is not possible due to its poor preservation.Comparison with the mandibles recovered in the Monseny area (La Mora site, see below) indicates that it may belong to the same genus discovered in the Montseny area.Interestingly, MGSB-39.483 is a large specimen with an obtuse angled angular, slightly different from the Montseny mandibles, which present a more straight angular.
Additionally, fragmentary undeterminated bones ) were also collected with the mandibular remains.
Montseny area (Barcelona Province), Catalonian basin: Several fossil-bearing localities have been recently discovered in the Triassic Buntsandstein facies of Montseny (Fortuny and Galobart, 2010), making it one of the best areas for the study of continental vertebrate ecosystems in the Iberian Peninsula.The ichnotaxa Rhynchosauroides cf.beasleyei, Rhynchosauroides sp., Chirotherium bar-thii and Synaptichnium sp. have been reported from the locality called Corral d'en Parera (Calzada, 1987) (Fig. 4).A recent review of the slabs collected in the first field campaign by Calzada and colleagues allowed the identification of additional ichnotaxa, including Isochirotherium (I.soergeli), Dicynodontipus, Rotodactylus and isolated tracks, probably referable to Procolophonichnium, preserving in some cases skin impressions (Valdiserri et al., 2009).
Olesa de Montserrat sites (Barcelona Province), Catalonian basin: The presence of nothosaur remains was cited by Almela and Llopis (1947).In their paper, the authors listed the presence of echinoderms, brachiopods, gastropods, ammonoids, bivalves, crustaceans, "nothosaur sp." and possibly the actinopterygian fish Colobodus.The presence of Colobodus was previously reported by Schmidt (1935).Unfortunately, all the vertebrate material was neither described nor figured and is now presumably lost.
The Olesa de Montserrat sites are included in the Olesa unit.This unit corresponds to the lower carbonate unit of the Muschelkalk facies, dated as late Anisian by biostratigraphic studies (See Marzo, 1980;Calvet and Mar-(See Marzo, 1980;Calvet and Marzo, 1994;Marquez-Aliaga et al., 2000 for further details).
Congost area (Barcelona Province), Catalonian basin: The vertebrate assemblage found in the Congost area comes from the lower Muschelkalk.Two localities are known to date in the area: Gorg Negre (Centelles, Barcelona) and Can Serra de l'Arca (Aiguafreda, Barcelona).
Both localities are included in the El Brull unit.This unit corresponds to the lower carbonate unit of the Muschelkalk facies dated as late Anisian by biostratigraphic studies (See Marzo, 1980;Márquez-Aliaga et al., 2000 for further details).
Alcover outcrops (Tarragona Province), Catalonian basin: The Alcover outcrops have yielded the best studied Triassic faunas of the Iberian Peninsula (e.g., Via-Boada and Villalta, 1975;Via-Boada et al., 1977;Sanz, 1983;Rieppel and Hagdorn, 1998;Cartanyà, 1999).These outcrops are located between the towns of Alcover, Mont-Ral and Montblanc.Those outcrops have been cited as Alcover, Mont-ral, or Mont-ral-Alcover, causing problems with the identification of the different localities in the literature.Here, we use the toponymical name of Alcover to refer to the classical outcrops present in the Alcover area, but also including under this name those of Mont-ral and El Pinetell.
An important percentage of the organisms from these outcrops were nektonic or planktonic (e.g., fishes, rep-tiles, cephalopods or swimming decapods).Benthonic forms like limulids, reptant decapods, holothurids, crinoids and brachiopods are rarer.Usually, the hard tissue has been destroyed by dolomitization, and the empty space has later been molded by a thin sheet of residual clay formed in pressure solution (Hemleben and Freels, 1977).
Vertebrates are well represented by a rich ichthyofauna (Beltan, 1972(Beltan, , 1975(Beltan, , 1984;;Cartanyà, 1999) with at least 12 actinopterygian families and the sarcopterygian Alcoveria (Beltan, 1972).Regarding the tetrapods, Cosesaurus aviceps was originally described as an "early protoavian" (Ellenberger and Villalta, 1974;Ellenberger, 1977Ellenberger, , 1978)), but it is obviously a protorosaurian archosauromorph close to Macrocnemus (Sanz and López-Martínez, 1984;Peters, 2000 and references therein).Several sauropterygians have been described, so this clade is the most represented among tetrapods at the sites.Placodonts are represented by a single small specimen.Although it is only possible to discern the outline, the presence of a bipartite carapace allowed its referral to the Cyamodontoidea and, tentatively, to the genus Psephoderma or Psephosaurus (Rieppel and Hagdorn, 1998).The specimen was originally kept in a private collection, but is now housed in the Museu Geològic del Seminari Conciliar de Barcelona.Nine specimens were assigned to Lariosaurus balsami (see Sanz, 1983), although three of them (MGSB-M509, and the specimens published by Sanz [1983, Pl. 3, Fig. A and B] were later referred to pachypleurosauroids (Rieppel and Hagdorn, 1998).The species Nothosaurus cymatosauroides (see Sanz, 1983) was described based on cranial and postcranial remains discovered in Alcover.An incomplete specimen was referred to Lariosarus calcagnii (see Rieppel and Hagdorn, 1998), although other authors discussed this attribution due to the fragmentary character of the specimen, which of the neural arch suggests that it was not coosified with the centrum.
The wrinkled enamel surface of MGB-30560 is not typical of a placodont, as the crowns in this group usually have a smooth surface (Sander, 2000).However, thin radial ridges starting from an apical point have been reported for just erupted teeth of Placodus (Owen, 1858) and ?Cyamodus sp.(see Dalla Vecchia, 1993).Such ridges are seen also on the inner surface of the enamel and they are visible on the dentine surface in the ?Cyamodus sp.tooth described by DallaVecchia (1993).The presence or absence of plicidentine can not be assessed with confidence due to the lack of the tooth base.Although it does not show the typical ichtyiosaurian hourglass shape, the centrum shows some resemblances to an ichthyosaur caudal (see Motani, 2000 for comparison).
The tooth described here strongly resembles those of Tholodus (see Sander and Mazin, 1993), but the fragmentary nature of the available material precludes a formal assignation.Moreover, the sediments of the site were deposited in a shallow marine carbonate ramp (Calvet and Tucker, 1988), where we would expect to find placodonts rather than ichthyosaurs, usually found in deposits of open marine settings.Nevertheless, it should be noted that the material is isolated and its bathymetric significance could be questionable.
Ichthyosaurs are virtually unknown in the Triassic of the Iberian Peninsula.The reported occurrence of Omphalosaurus in Spain (Sander and Mazin, 1993) was later shown to be incorrect (Sander and Faber, 1998), so the only evidence of Triassic ichthyosaurs is that reported by Knoll et al. (2004) from the Keuper of La Manzanera (Teruel Province), although no material has been figured or described yet.Placodonts occur in the Muschelkalk of Spain and possibly in the Keuper as well (their remains have been reported from about 10 localities, for further details see Sanz et al., 1993 andBardet et al., 2008 andbelow).
Collbató area (Barcelona Province), Catalonian basin: An isolated vertebra (MGB-32276) and a single tooth (MGB-30560) (Fig. 5) were recovered in the La Pedrera d'en Rogent locality.These are the first vertebrate remains reported from this locality.This locality was previously known for the presence of echinoderms (Calzada and Gutiérrez, 1988;Smith and Gallemí, 1991) and associated invertebrate fauna (gastropods, bivalves and ammonoids) (Smith and Gallemí, 1991).The Collbató site occurs in the upper carbonate unit of the Muschelkalk facies and was dated as Ladinian (Rosell et al., 1975).Later, other authors (Calzada and Gutiérrez, 1988;Smith and Gallemí, 1991) also accepted a Ladinian age for the echinoderm-bearing horizons; tetrapod remains were recovered from the same horizons, included in the Collbató unit.
Only a tooth crown of a durophagous reptile and a vertebral centrum has been recovered from this site, found close to each other in the same bed.
The tooth crown (MGB-30560) is still embedded in the rock and damaged (Fig. 5).Part of the dentine was lost, so the inner surface of the enamel is exposed.It is buttonlike with an elliptical outline and is 20.6 mm long and 16.8 mm wide.It has a central elevation with a pointed end, as we can infer from the internal surface.The enamel is almost 1mm-thick and shows numerous long and irregular radial wrinkles on its inner surface.The wrinkles sometimes bifurcate near the apical part of the crown.There is no wear facet.Thus, this tooth was probably not fully functional yet.
The 'Perleidiformes' are a heterogeneous and cosmopolitan group of Triassic fishes.Gardiner and Schaeffer (1989) have questioned the monophyly of this group, because 'perleidiform' taxa share a combination of characters that seems to be unique among primitive actinopterygians.Therefore, the specimens above briefly described are tentatively attributed to the order 'Perleidiformes' (sensu Berg, 1937) based on the following characters: body outline fusiform; gape commonly moderate; snout with nasals searated by a large (post)rostral; almost vertical preopercular with an expanded dorsal region; scales deeper than long in the anterior portion of the flank, with the posterior borders often denticulated; rays of dorsal and anal equal in number to radials; caudal fin heterocercal with several epaxial rays.
Odèn outcrop (Lleida Province), Pyrenean basin: Several vertebrate remains have been recovered from these carbonates.The fossil fishes do not show any sign of dolomitzation, are well-preserved and associated with ophiuroid echinoderms and bivalves (Lehman, 1964).Recent fieldwork in a new locality called Can Xivill led to the discovery of new specimens assigned to Colobodus (Mutter and Cartanyà, in prep.), some undetermined perleidiforms and Saurichthys (MGB-49.761 and IPS-54.939).Specimens of the latter genus are described here (Fig. 7).Some specimens are articulated and some are disarticulated.All remains are preserved in a finely laminated, ochre-grey clayish limestone layer.This locality corresponds to the Laminated Limestone unit of the up-Laminated Limestone unit of the upper carbonate unit of the Muschelkalk facies.Its age is basal Carnian, as revealed by the palynomorph assemblage found at the Odèn site in the transition between this unit and the Keuper facies (Calvet et al., 1993) A preliminary description of two specimens (MGB-49.761and IPS-54.939) is provided here.Specimen MGB-49.761represents a nearly complete lower jaw in dorsal view, with an approximate size of 40 mm length (Fig. 7).The dentition can be observed on the dentary, Jeroni.Surprisingly, no vertebrate remains have been described from this area in the past and only Wurm (1913) noted the presence of unidentified fish scales.Recently, several fish specimens (some of them almost complete) have been collected in the Sant Jeroni locality, and are described below.The assemblage is dominated by perleidiformes actinopterygians (Fig. 6), but specimens representing other groups are under study.All remains come from the upper carbonate unit of the Muschelkalk facies, supposed to be coeval (late Ladinian) with the Alcover sites by Via-Boada and colleagues (1977).SYSTEMATIC PALEONTOLOGY OSTEICHTHYES Huxley, 1880 ACTINOPTERYGII Cope, 1887 PERLEIDIFORMES Berg, 1937 Perleidiformes indet.
The total body length of these fusiform specimens (CE-RAM-R001 to CERAM-R020) ranges from 40 to 55 mm.The specimens are covered by thick ganoid scales with a denticulated posterior margin.The skull represents 20% of the total body length.The width of the gape is moderate.The opercular is much larger than the subopercular and the preopercular is almost vertical and shows an expanded dorsal process of typical perleidid shape (Brough, 1931;Tintori and Sassi, 1992;Tintori and Lombardo, 1996).Although present, the number of branchiostegal rays cannot be assessed with confidence due to the poor preservation of the specimens.Most of the elements of the orbital series cannot be well distinguished (Fig. 6).
The upper jaw is composed of a moderately-sized maxilla and a small premaxilla, while the lower jaw is wedgeshaped with conical-pointed teeth (Fig. 6).
The pectoral fins are composed of at least 10 lepidotrichia; the pelvic fins are at the level of the 9 th or 10 th longitudinal scales row, and bear 7 or 8 lepidotrichia; the dorsal fin is placed between the 20 th and the 27 th scales row.It consists of at least 12 lepidotrichia and is triangular in outline.The anal fin is similar in shape, has at least 10 lepidotrichia and occurs between the 17 th and the 19 th scales row.The caudal fin is almost symmetrical and consists of 30 lepidotrichia, with 7 or 8 epaxial rays and a very short axial scaly lobe (Fig. 6).The squamation comprises 37-38 tranversal scales rows, and the scales are mostly deep, except in the caudal region where they are rather rhomboid (Fig. 6).
All characters described here suggest perleidiform affinities.However, it is necessary to note that the diagnostic characters of this group have been exhaustively discussed in the literature (Brough, 1931;Schaeffer, 1955; agnostic characters of this genus have been emended and revised (Mutter et al., 2008;Wu et al., 2009, in press).Unfortunately, most of these characters are not preserved in the specimens recovered from the Odèn locality.The general morphology of the snout (long, slender and acuminate), and the dentition (series of conical teeth) allows us to assign them, at least, to the Saurichthyidae, showing close affinities to the lower jaw of a large Saurichthys consisting of one row of 34 teeth, on each side, intercalated with more numerous tiny teeth.These teeth are bluntconical in shape, and are slightly curved backwards.The main teeth do not exceed 0.75 mm in height and measure 0.4 mm in diameter.
Only postcranial elements were previously reported in the literature from this site, and assigned to the actinopterygian Saurichthys (Lehman, 1964).Recently, the di- specimens from the Middle Triassic Monte San Giorgio site described by Rieppel (1985).Vilanova de la Sal area (Lleida Province), Pyrenean basin: Some fish remains and a partially articulated sauropterygian skeleton were collected in this new site.The fishes are housed in the Institut d'Estudis Ilerdencs (IEI-VvS-4929P to VvS-4939P).Preliminary observations of the ichthyofauna suggest the presence of Eosemionotus and Peltopleurus, the latter being the most frequent.A detailed study of the sauropterygian specimen (Fig. 8) is beyond the scope of this paper, so it will be only briefly described here.This new site is located in the Laminate Limestone unit of the upper carbonate unit of the Muschelkalk facies.It is dated by its palynological content as basal Carnian (Calvet, 1996).SYSTEMATIC PALEONTOLOGY SAUROPTERYGIA Owen, 1860 EOSAUROPTERYGIA Rieppel, 1994PACHYPLEUROSAURIA Nopcsa, 1928 Pachypleurosauria gen. et sp. indet.The specimen is contained in four slabs (IPS -51362ad) conforming to a partial skeleton of a small tetrapod.The first slab was found ex-situ; further search in the original position.The left ilium is also present.The left femur is almost complete; it lacks only part of the distal epiphysis.The shorter tibia and fibula are not connected to the femur but are close to its distal epiphysis.At least three metatarsals and probably the astragalus and calcaneum are present, although they are not preserved in their original position.Two gastral ribs with the same morphology as that in IPS-51362b are preserved in this slab, together with some additional bones that cannot be identified due to preservation nature.The fourth slab IPS-51362d only preserves a rather small isolated gastral rib.
We cannot use diagnostic cranial characters to refer the specimen to Pachypleurosauria because the skull is lacking.Two observable synapomorphies on the postcranial skeleton are the lack of expansion of the sacral ribs and the reduction of the process-like dorsal iliac blade of the ilium (Rieppel, 2000).The humerus is the strongest bone in the limb skeleton.It is constricted medially and only weakly curved, resembling the general pachypleurosaurian pattern (Rieppel, 1989), as does the less developed femur (Lin and Rieppel, 1998).Moreover, a number of three sacral vertebrae have been reported as characteristic of pachypleurosaurs, while lariosaurs are supposed to have four or five sacral vertebrae (Cheng et al., 2004).However, the inclusion of Keichousaurus (with 3 sacral vertebrae) within pachypleurosaurs (Young, 1958) has been rejected by Holmes et al. (2008), and thus this character should be taken with caution as diagnostic for pachypleurosaurs.The shape of the pubis, ilium, ischium and coracoid, and the general proportions of the postcranial suggest pachypleurosaurian affinities for the specimen.
The presence of pachypleurosaurs in the studied area is restricted to one badly preserved specimen from the Lower Muschelkalk of the Congost area (Sanz, 1983).
same area allowed the finding of three additional in-situ slabs, at the same level and close to each other.The high degree of skeletal articulation (only a few bones are slightly displaced), the lack of duplicated bones, and the size of the remains preserved on the different slabs suggest they belong to a single individual.The slab IPS-51362a contains seven vertebrae (probably cervical) in lateral view.IPS-51362b shows the left side of the anterior part of the trunk, with 11 partial dorsal vertebrae (represented only by the neural spines; centra are not preserved) and at least five ribs.The left coracoid and part of the left clavicle are also present.The left forelimb is almost complete although irregularly preserved, with the humerus highly damaged.The distal part of the radius is underlying the well-preserved ulna.At least one carpal is present, together with three metacarpals, two short phalanges and two or three much shorter phalanges.An isolated, V-shaped mid-gastral rib occurs near the left manus.IPS-51362c contains four presacral, three sacral, and 15 caudal vertebrae.The neural spine is visible in lateral view in the last four preserved caudal vertebrae.The neural arches as a whole are slightly taller than the corresponding centra, and the neural spine is slightly posteriorly directed.At least one long dorsal rib is exposed on the right side.The small ilium presents a reduced dorsal iliac blade, and its small size and the position of the ribs suggest that it only received three sacral ribs with unexpanded ends.Only the proximal epiphysis of the right femur is present, contacting the right ilium, with the rest preserved as a shallow impression.The right ischium and pubis are preserved.The obturator foramen forms a slit in the posterior margin of the pubis, and the ischium is also weakly notched (as reported for small specimens of Serpianosaurus [Rieppel, 1989]).
Considering the left part of the body, one long and several short left ribs are preserved, displaced from their However, some specimens from Alcover referred to Lariosaurus by Sanz (1983) were later argued to be pachypleurosaurs by Rieppel and Hagdorn (1998).

Discussion: Paleogeography and vertebrate palaeontology
Integrating vertebrate palaeontology with other disciplines (e.g.stratigraphy) can be a powerful tool to upgrade paleogeographic maps.Using the maximum consensus of several paleogeographic reconstructions of the Iberian Peninsula and southern Europe during the Late Permian and the Triassic (Garrido-Mejías and Villena-Morales, 1977;Sopeña et al., 1988;Ziegler, 1990;López-Gómez et al., 2002;Vera, 2004;Sopeña et al., 2009;Linol et al., 2009), and the results obtained from the vertebrate localities above described, we propose six maps corresponding to the Iberian area during six different intervals of time (Fig. 9), in order to discuss vertebrate finds and their palaeobiogeographic significance during the analyzed time span.We include the number of each locality, as referred to in the material and methods chapter, so that they can be correlated with the figures (Figs. 1, 9).

Late Anisian (Fig. 9D)
The continental environments that characterized the Iberian Peninsula during the early-middle Anisian, changed into shallow marine at its end, because of the Muschelkalk transgression progressed from east to west (Linol et al., 2009).This environmental-lithological change from mudflats to evaporitic sabkhas (Calvet and Marzo, 1994;López-Gómez et al., 2002) is recorded in several areas.The Congost area (6) in the northeastern Iberian Peninsula yielded vertebrate localities with fossil fishes and fragmentary remains of pachypleurosauroid sauropterygians (Llopis-Lladó, 1942;Sanz, 1983).Additionally, indeterminate bones were collected in the Olesa de Montserrat area (5) (See above).These two are the only localities yielding direct vertebrate remains to date.

Early Triassic (Fig. 9B)
Sedimentation during both the Permian and the Triassic occurred in braided river settings under arid climates (Arche and López-Gómez, 2006;Linol et al., 2009).The palynomorph (Díez et al., 2005) and vertebrate records indicative of an Early Triassic age are not found in the Iberian Peninsula.The causes for this fact could be the presence of a stratigraphic hiatus and/or the existence of arid environments that prevented optimal conditions for life and the preservation of organic remains (Bourquin et al., 2007).

Early-middle Anisian (Fig. 9C)
This time interval is characterized by the predominance of fluvial deposits with development of palaeosols that gradually change into marine deposits with the Muschelkalk transgression (Linol et al., 2009).Palynomorph assemblages and macrofloral remains are common and their study in the Iberian Peninsula and the Balearic Islands (Díez et al., 2005) allows the dating of the rocks.Tetrapod ichnofaunas recovered in the northeastern part of the Iberian Peninsula (specially in the Montseny Area) occur in continental settings (such as fluvial deposits), presenting a predominance of the "lacertoid" Rhynchosauroides, over other ichnogenera such as the crurotarsal Chirotherium, Isochirotherium, Rotodactylus, Procolophonichnium, and Synaptichnium, the two last ones being the less common.These footprints could be considered as characteristic of the global late Olenekian -early Anisian chirothere-dominated footprint fauna.
The osteological record from the Catalonian basin is especially important, yet as to date it is the unique basin from the Iberian Peninsula that yields direct vertebrate remains (bones and teeth) from this age.The vertebrate fauna from those fluvial deposits consists of temnospondyl amphibians (capitosaurs) associated with much rarer archosauriforms and procolophonoid remains as in La Mora site in the Montseny area (4) (Gaete et al., 1993(Gaete et al., , 1996;;Fortuny et al., 2009).This supports the idea of archosauriforms and procolophonoids being potential trackmakers.However, no footprint evidence can be referred to amphibians to date.In addition, these fauna may be similar with upper Buntsandstein fauna recovered in the German basin.
Several early-middle Anisian tetrapod-bearing localities are reported from other sites of the Iberian Peninsula.Tetrapod footprints are known from Moncayo sites (Zaragoza) (17) (Navas, 1906;Leonardi, 1959), Molina work is required to evaluate these faunal similarities.
5.6.Carnian (Fig. 9F) The fall of the sea level was the main trend from late Ladinian until the first steps of the Carnian.In general terms, during the Carnian there was abundant sedimentation of evaporites (Ortí, 2004).Nevertheless, it is possible to find lower-middle Carnian vertebrate-bearing sites with clear marine influence, representing coastal environments (Knoll, 2004;Quesada et al., 2009).
To summarize the palaeobiogeographical data, the Permian vertebrates occur in alluvial deposits whereas the Early Triassic vertebrate localities are unknown, maybe for the presence of stratigraphic hiatus and/or for the presence of arid ambients.The major part of the Anisian was characterized by the presence of terrestrial fauna, which is consistent with the fluvial deposits that existed during this stage in the greatest part of the Iberian area.This tendency changed by late Anisian times with the beginning of a transgression, resulting in the evolution to shallow marine and coastal environments.This correlates with a change of the faunal composition, including tetrapod footprints in inter-and supratidal carbonate flats and fishes and sauropterygians in fully marine ambients.Later, the Ladinian presented a wide diversity of marine environments (e.g.shore, lagoons, tidal flats, reefs…); the vertebrate fauna is dominated by fishes and marine reptile taxa.However, moderate sea level downfalls resulted locally in the presence of nonmarine environments where tetrapod footprints were preserved.Finally, the Late Triassic vertebrate fauna is represented by fishes and sauropterygians recorded in coastal environments.

Ladinian (Fig. 9E)
The marine conditions settled in the Iberian region during the late Anisian and persisted during the whole Ladinian (López-Gómez et al., 2002), and there was a wide diversity of coastal and marine depositional environments (shores, lagoons, tidal flats, reefs, etc.).Ladinian vertebrates in northeastern Iberian Peninsula are especially well known in the classical localities of Alcover (7), traditionally considered as originated in a shallow, lagoonal basin within an extended reef complex (Hemleben and Freels, 1977;Alafont and Sanz, 1996;Rieppel and Hagdorn, 1998).Further work is needed to detail the depositionary environment and vertebrate fauna from Móra d'Ebre-Camposines (Tarragona) (9) and Collbató sites (Barcelona) (8).

Summary and conclusions
The Permian and Triassic vertebrates from the Catalonian and Pyrenean basins of the Iberian Peninsula are ana Valdiserri, Alba Vicente, Manel Méndez and Jordi Pasques, who made possible the prospecting and the excavations.

References
Alafont, L. S., (1992) ) the data discussed in the present work reveals the importance to compare the faunas recovered in the Iberian Peninsula with the German basin in order to discuss its possible similarities.In addition, here we demonstrate the potential of Iberian material and provides good perspectives for future work, by means of a more extensive and detailed study of these rather unknown faunas.

Acknowledgements
Our special thanks go to Antoni Lacasa and Javier Lozano (Institut d'Estudis Ilerdencs), Jaume Gallemí (Museu de Geologia de Barcelona) and Sebastià Calzada (Museu Geologic del Seminari Conciliar de Barcelona) for the access to the collections under their care and for providing interesting information about the sites; we are deeply indebted to Francisco Martínez-Paul, who kindly provided the pachypleurosaur specimen; to Lluís Ferrer-Condal, Jordi Galindo, Josep Magrans, Jordi Tritlla, Mariano Marzo and Rafel Mirabal for providing important information about the vertebrate findings; to Fabio M. Dalla Vecchia, Raoul Mutter, Andrea Tintori and Cajus Diedrich who read an early draft and made useful comment which surely improved the present manuscript; the quality of this manuscript was improved with the comments of the reviews of Alfredo Arche and Spencer Lucas as well as the editor José López-Gómez.Judit Marigó improved the English text; and last but not least, our thanks to the field crews, especially Isabel Vila, Di-