Atti Soc. it. Sci. nat. Museo civ. Stor. nat. Milano, 137/1996 (I-II): 101-126, Settembre 1997 Alessandro Garassino (*) The macruran decapod crustaceans of thè Lower Cretaceous (Lower Barremian) of Las Hoyas (Cuenca, Spain) Abstract - The macruran decapod crustaceans of thè Lower Cretaceous (Lower Barre¬ mian) of Las Hoyas have already been thè subject of a study at thè beginning of thè 90s. The examined specimens were ascribed to thè species Delclosia macinelli Rabadà, 1993 (infraor- der Caridea Dana, 1852, indeterminate family) and Pseudastacus llopisi Via, 1971 (infraorder Astacidea Latreille, 1803, family Nephropidae Dana, 1852) respectively. The analysis of thè wide sample of macruran decapod crustaceans, housed in thè Autonomous University of Ma¬ drid and in thè private collection of Mr. Armando Di'az-Romeral, allowed to carry out a de- tailed morphological description of both species, by emphasizing new features previously not observed and deepening thè analysis of other features already known in thè past. Unlike thè originai description, thè study of thè examined sample has so allowed thè ascription and sy- stematic revision of thè two species: in fact Delclosia martinelli Rabadà, 1993 has been ascri¬ bed to thè family Atyidae de Haan, 1849 while Pseudastacus dopisi Via, 1971 has been ascri¬ bed to thè living genus Austrapotamobius Skorikov, 1907 (family Astacidae Latreille, 1802) on thè basis of some common features, such as thè structure of thè chela of pereiopod I, thè number of postorbitai teeth and thè structure of thè tail fan. The presence of Austrapotamo¬ bius Skorikov, 1907 in Las Hoyas outcrop represents thè first report of this genus in thè fossil record. Resumen - Los crustàceos decàpodos macruros del Cretàcico inferior de Las Hoyas (Cuenca, Espana). Los crustàceos decàpodos macruros del Cretàcico inferior de Las Hoyas (Cuenca, Espana) han sido ya objeto de estudio desde los primeros anos noventa de parte de Rabadà (1993). Los ejemplares fueron atribuidos respectivamente a la specie Delclosia martinelli Ra¬ badà, 1993 (infraorden Caridea Dana, 1852, familia indeterminada) y Pseudastacus dopisi Via, 1971 (infraorden Astacidea Latreille. 1803, familia Nephropidae Dana, 1852). E1 anàlisis del abundante muestra de crustàceos decàpodos macruros. conservados en la Universidad Autonoma de Madrid y de la colección privada del Sr. Armando Dfaz-Romeral, ha echo posi- bile la revisión y atribución sistemàtica de las dos especies: Delclosia martinelli Rabadà, 1993 ha sido asignada correctamente a la familia Atyidae de Haan. 1849, mientras que Pseudasta¬ cus dopisi Via. 1917 acaba de ser atribuida al gènero viviente Austrapotamobius Skorikov, 1907 (familia Astacidae Latreille. 1802). gratias ad alguna caracteristica comùn. còrno el ro¬ stro con un diente supraoral, un sólo diente postorbitai, la quela del pereiópodo I con un evi¬ dente escalón en el inargen interno del index que se corresponde con la articulación con el dàctilo y el telson, subdividido en dos partes con forma de una transversal. La existencia de gènero Austrapotamobius Skorikov. 1907 en el yacimiento de Las Hoyas representa su primer indicio en el registro fósil. (*) Museo Civico di Storia Naturale. C.so Venezia. 55 - 20121 Milano, Italia 102 ALESSANDRO GARASSINO Riassunto -I Crostacei decapodi macruri del Cretacico inferiore (Barremiano inferiore) di Las Hoyas (Cuenca, Spagna). I crostacei decapodi macruri del Cretacico inferiore (Barremiano inferiore) di Las Hoyas (Cuenca, Spagna) sono già stati oggetto di studio nei primi anni novanta. Gli esemplari esaminati furono attribuiti rispettivamente alle specie Delclosia martinelli Rabadà, 1993 (in- fraordine Caridea Dana, 1852, famiglia indeterminata) e Pseudastacus llopisi. Via, 1971 (in- fraordine Astacidea Latreille, 1803, famiglia Nephropidae Dana, 1852). L’analisi dell’abbon¬ dante campione di crostacei decapodi macruri, conservato all'Università Autonoma di Ma¬ drid e nella collezione privata del Sig. Armando Dlaz-Romeral, ha reso possibile una accurata descrizione morfologica di entrambe le specie nella quale vengono evidenziati nuovi caratteri non osservati in precedenza, approfondendone altresì l'analisi di altri già conosciuti in passa¬ to. Rispetto alla descrizione originale, lo studio del campione esaminato ha reso così possibile l’attribuzione e revisione sistematica delle due specie: Delclosia martinelli Rabadà, 1993 è sta¬ ta infatti assegnata alla famiglia Atyidae de Haan, 1849 mentre Pseudastacus dopisi. Via, 1971 viene attribuita al genere vivente Austropotamobius Skorikov, 1907 (famiglia Astacidae La¬ treille, 1802) in base ad alcuni caratteri comuni, quali la struttura della chela del pereiopode I, il numero dei denti postorbitali e la struttura del ventaglio caudale. La presenza di Austropo¬ tamobius Skorikov, 1907 nel giacimento di Las Hoyas rappresenta la prima segnalazione di questo genere nel record fossile. Key words: Crustacea, Decapoda, Lower Cretaceous, Spain Introduction The Lower Cretaceous (Lower Barremian), outcropping in thè southern part of thè «Serranfa de Cuenca» about 30 km E of thè city of Cuenca (Fig. 1), consists of two sedimentary cycles: «E1 Collado» and «La Huérguina» Formations. The Las Hoyas outcrop is located inside «La Huér- guina» Formation, characterized by carbonatic deposits originated by conti- nuous accumulations of alluvional and lacustrine materials (Gómez- Fernàndez & Meléndez, 1991, Fregenal Martinez & Meléndez, 1993 and Fregenal Martinez & Meléndez, 1995). The numerous excavations, started in 1985 further to a report by Mr Armando Diaz-Romeral, an amateur naturalist, and Mr Santiago Prieto, brought to light a rich vertebrate and invertebrate fauna, typical of lacustri¬ ne environment. One of thè peculiar features of this outcrop is thè perfect state of preservation of thè discovered specimens, most of which preserve traces of soft parts and are almost always found articulated. Fig. 1 - Location of Las Hoyas outcrop (thè asterisk shows thè outcrop). THE MACRURAN DECAPOD CRUSTACEANS OFTHE LOWER CRETACEOUS 103 The tetrapods, very rare in this outcrop, include anuran amphibia and salamanders (Evans & Milner, Ms and Evans & Milner, 1995), turtles, li- zards belonging to thè genus llerdaesaurus (Barbadillo & Evans, 1995), me- tasuchian crocodiles with thè genus Lisboasciiiras (Buscalioni & Ortega, 1994 and Ortega & Buscalioni, 1995), remains of ornitomimosaurid dino- saurs, ascribed to thè genus Pelecanimimus (Pérez-Moreno et alii, 1994 and Pérez-Moreno & Sanz, 1995) and remains of birds, ascribed to thè two ge¬ nera Iberomesornis and Concornis (Sanz et alii, 1988, Sanz & Bonaparte, 1992, Sanz & Buscalioni, 1992 and Sanz & Buscalioni, 1994). The most frequent vertebrates in thè lithographic limestone are thè bony fishes (actinopterygians and sarcopterygians), subject of study of many papers (Poyato-Ariza, 1989, 1991, 1993, 1994, 1995a, 1995b, Poyato- Ariza & Wenz, 1990, Wenz & Poyato-Ariza, 1994,1995 and in press). However, thè most frequent fossils in Las Hoyas outcrop are represen- ted by crustacean remains: among these, rare and not yet described, there are copepods, probable mysidaceans, peracarids, isopods and ostracodes (Martmez-Delclòs & Nel, 1995 and Rodriguez-Làzaro, 1995); on thè con- trary, thè macruran decapod crustaceans, subject of previous papers (Ra- badà, 1990, 1993) are particularly frequent. Among thè other invertebrates, bivalves and gastropods are very rare, while insects are usually frequent (Martmez-Delclòs et alii, 1995 and Nel et alii, 1993a, 1993b, 1993c). Moreover remains of charophytes, briophytes, ferns, cicadophytes (Za- mites), gnetales (Drewria), conifers (Pagiophyllum, Brachyphyllum, Sheno- lepis, Cupressinoclcidus and Frenolepis) and angiosperms were discovered in thè outcrop. On thè contrary, trackways belonging to invertebrates (Frege- nal Martmez et alii, 1995) and vertebrates (Fregenal Martinez & Morataìla, 1995) are very rare. Previous studies on thè macruran decapod crustaceans of Las Hoyas In thè two outcrops, «La Pedrera» and «La Cabrura», of thè Lower Cretaceous (Upper Berrisian-Lower Valanginian) of Montsec (Lleida, Bar¬ celona) a freshwater fauna was discovered, similar for many aspects to Las Hoyas association (Lower Barremian). Via (1971) ascribed 13 macruran de¬ capod crustaceans discovered in Montsec outcrops to thè two species Pseu- dcistacas dopisi (infraorder Astacidea Latreille, 1803, family Nephropidae 1852) and Oplophorus roselli (infraorder Caridea Dana, 1852, family Oplophoridae Dana, 1852). The following discovery of thè rich macruran decapod crustaceans fau¬ na in Las Hoyas outcrop allowed to carry out a comparative analysis of thè two carcinological faunae. The better state of preservation of thè examined specimens allowed Rabadà (1990, 1993) to identify in this outcrop thè same species Pseudastacus dopisi Via, 1971 and to establish instead thè new ge¬ nus Delclosia Rabadà, 1993 with thè species D. martinelli Rabadà, 1993 (in¬ fraorder Caridea Dana, 1852, indeterminate family). The following comparison between D. martinelli Rabadà, 1993 and Oplophorus roselli Via, 1971 by Rabadà, pointed out some common features, such as thè presence of small chelae in pereiopods I-IL thè subround shape of thè pleura of somite II and thè particular elongation of somite VI, which al¬ lowed to ascribe thè species by Via to thè same genus Delclosia Rabadà, 1993. 104 ALESSANDRO GARASSINO Nowadays, it is difficult to establish if D. rosei li (Via, 1971) and D. mar¬ tinetti Rabadà, 1993 are two different specific entities or whether they are synonymous, without a careful analysis of thè carcinological sample of Montsec. On thè other hand, thè originai description of thè species (Via, 1971, pag. 608; Rabadà, 1993, pag. 354) and their iconographic reconstructions (Via, 1971, fig. la; Rabadà, 1993, figs. 3, 4) show a particular morphological feature which leads us to consider them as two distinct species. In fact, D. roselli (Via, 1971) has a long and markedly upwards bent rostrum, hearing seven suprarostral teeth in thè proximal third while D. martinetti Rabadà, 1993 has a long and straight rostrum, hearing at least 25/30 small supraro¬ stral teeth along its whole length. Preservation modalities and materials The macruran decapod crustaceans examined in this study are preser- ved in light-brown densely laminate thin layers of lithographic limestone, flattened on thè layer surface. The soft consistency of thè surrounding rock makes their preparation easy. The collections belonging to thè Autonomous University of Madrid and to Mr. Armando Diaz-Romeral consist of about 1000 specimens of ma¬ cruran decapod crustaceans in different States of preservation. The prelimi- nary analysis brought to an initial selection of 83 specimens of Delclosia martinetti Rabadà, 1993 and 550 specimens of Pseudastacus llopisi Via, 1971. A final sample, thè subject of this study, has been subsequently selec- ted from this sample of 633 specimens: it consists of 50 specimens, 22 of which belonging to Delclosia martinetti Rabadà, 1993 and 28 to Pseudasta¬ cus dopisi Via, 1971. The study on thè decapod crustaceans of thè Lower Cretaceous of Las Hoyas is part of a research programme on Mesozoic macruran decapod crustaceans that thè Invertebrate Palaeontology Department of thè Museo di Storia Naturale di Milano has been carrying out for niany years on mate¬ rials from its own and other Museums’ collections. Up to now this program¬ me brought to thè description of important Italian and foreign Mesozoic faunistic assemblages, such as thè Triassic association of thè Ambilobè re- gion (NW Madagascar) (Garassino & Teruzzi, 1995), of Cene (Seriana Val- ley, Bergamo - N Italy) (Pinna, 1974), of Prati di Rest (Valvestino, Brescia - N Italy) (Pinna, 1976), of Ponte Giurino (Imagna Valley, Bergamo - N Italy) (Garassino & Teruzzi, 1993) and of Carnia (Udine, NE Italy) (Garassino, Teruzzi & Dalla Vecchia, 1996); thè Lower Jurassic fauna of Osteno (Luga¬ no Lake, Como - N Italy) (Pinna, 1968,1969; Garassino & Teruzzi, 1990; Te¬ ruzzi, 1990 and Garassino, 1996) and thè Cretaceous assemblages of Trebi- ciano (Trieste, NE Italy) (Garassino & Ferrari, 1992), of thè Lebanese out- crops (Garassino, 1994), of Vernasso (Udine, NE Italy) (Garassino & Teruz¬ zi, 1995), of Pietraroia (Benevento, S Italy) (Bravi & Garassino, in press), of Petina (Alburni Mounts, Salerno - S Italy) (Bravi & Garassino, in press) and of Torrente Cornappo Valley (Udine, NE Italy) (Garassino, in press). Acronyms. LH: Las Hoyas; ADR: Armando Diaz-Romeral Collection 105 THE MACRURAN DECAPOD CRUSTACEANS OFTHE LOWER CRETACEOUS Abbreviations R - rostrum Ex - exopodite E - eye di - diaeresis t - telson P - propodus Pt - protopodite D - dactylus En - endopodite I - index SYSTEMATICS Infraorder Caridea Dana, 1852 Family Atyidae de Haan, 1849 Genus Delclosia Rabadà, 1993 Delclosia martinelli Rabadà, 1993 Figs. 2,3,10,11 1993 - Delclosia martinelli - Rabadà, p. 356, Fig. 3,Tab. 1 Diagnosis. Subrectangular carapace; long rostrum with at least 25 forwards protuded suprarostral teeth; pereiopods I-II hearing very small chelae; pereiopods III-V longer than thè preceding ones; somite II with su¬ bround pleura overlapping that of somites I and III; somite VI strongly elongate; exopodite with diaeresis. Material. 144 specimens in different States of preservation belong to thè collection of thè Autonomous University of Madrid; 22 complete speci¬ mens were studied in detail in order to deepen thè analysis on this species, which adds new data to thè originai description by Rabadà (1993), based on a sample of only 9 specimens. 21 specimens are preserved in lateral view and 1 in dorsal view. LH98, LH206, LH219, LH1122, LH1351, LH1852, LH1855, LH2646, LH2875, LH2923, LH2974, LH3026, LH6948, LH13043, LH13256, LH13323, LH13567, LH14209, LH14294, LH14360, LH14361, LH14362 Description. It is a small-sized caridean with thin and completely smooth exoskeleton, 1.5 to 3 cm in length. Carapace. In lateral view, thè carapace (Fig. 2) has a subrectangular shape and gets slightly narrow toward thè anterior margin for thè slight cur¬ vature of thè ventral margin. The dorsal margin is straight, while thè poste- rior margin, strengthened by a thin marginai carina, is slightly sinuous, with a slight concavity in thè lower third, partially covering somite I. The ventral margin has a curvilinear trend. The dorsal margin extends into a long and straight rostrum hearing many identical and forwards protuded suprarostral teeth. Rabadà (1993, p.358) pointed out in thè examined specimens thè pre- sence of a rostrum with 30 small suprarostral teeth. From thè analysis of thè whole sample and above all thè sample used for this study, it is difficult to observe and quantify thè number of suprarostral teeth because of thè fragi- lity of thè rostrum which is usually broken or badly preserved. Neverthe- less, thè analysis of nine specimens (LH98, LH219, LH1351, LH2974, LH1852, LH13043, LH13256 and above all LH1122 and LH1855) confir- 106 ALESSANDRO GARASSINO med thè presence of at least 25 small identical and forwards protuded su- prarostral teeth, arranged along thè whole rostrum, which seems to be strengthened by a thin longitudinal median carina extending from thè base to thè distai extremity. The ocular incision is narrow and shallow and thè antennal and pterygostomial angles are not very marked. No traces of groo- ves, carinae and spines can be observed on thè surface of thè carapace. Abdomen. The abdomen shows thè typical, almost right-angle curvatu¬ re of carideans between somites III-IV. Somites I-V have a subrectangular shape and uniform length. Somite II has a strongly subround pleura over- lapping that of somites I and III. The pleurae of thè other somites are roun- ded and strengthened by a thin marginai carina. The posterior margin of so¬ mite III is slightly sinuous, while that of somites IV-V is posteriorly projec- ting. Somite VI is strongly elongate, reaching twice thè length of thè other somites. The telson has a triangular shape and pointed distai extremity. The uropods, lacking any ornamentation, have thè same length, a rounded distai extremity and are not longer than thè telson. The exopodite shows a roun¬ ded diaeresis. Cephalic appendages. Badly preserved in almost all specimens. The eye is supported by a short eye-stalk. The antennulae consist of three articula: thè lst and thè 2nd are thin and elongate, while thè 3rd is short and stocky. It is impossible to assess thè length of thè antennular flagella. The scapho- cerite has a triangular shape and pointed distai extremity. The carpocerite of thè antennae has a subrectangular shape. A flagellum, almost as long as thè body, is articulated to it. Thoracic appendages. They are preserved only in eight specimens (LH219, LH1855, LH2875, LH2974, LH13043, LH14209, LH14294, LH14361). The 3rd maxilliped is not preserved. Pereiopods I-II, with thin articula, have very small chelae with internai dactylus. Pereiopods III-V, with thin and elongate articula, have a terminal dactylus and are about 1/3 longer than thè first two pairs of pereiopods. Abdominal appendages. They are visible in almost all specimens. The pleopods consist of a subrectangular sympodite to which two elongate mul- tiarticulate flagella are articulated. R Fig. 2 - Delclosia martinelli Rabadà, 1993, carapace reconstruction, line drawing. 107 THE MACRURAN DECAPOD CRUSTACEANS OFTHE LOWER CRETACEOUS Fig. 3 - Delclosia martinetti, Rabadà, 1993, reconstruction. Observations Carideans are very rare in thè tossii record and their morphological features are not well known because of their poor state of preservation. The most ancient genera known to date, Acanthinopus Pinna, 1974 and Leiothorcix Pinna, 1974, were discovered in thè Calcare di Zorzino (Norian, Upper Triassic) of Bergamo Prealps (Cene, Seriana Valley - Bergamo, N Italy) (Pinna, 1974). Another form, Pinnacaris Garassino & Teruzzi, 1993, was described in thè Arginiti di Riva di Solto (Sevatian, Upper Norian- Lower Rhaetian, Upper Triassic - depending on thè authors) of Ponte Giu¬ rino (Imagna Valley - Bergamo, N Italy) (Garassino & Teruzzi, 1993). Glaessner (1969) ascribed to Jurassic only thè genus Udorella Oppel, 1862 (family Udorellidae Van Straelen, 1924). The same author ascribed al- so three incertae sedis Jurassic genera to carideans: Blaculla Miinster, 1839, Hefriga Miinster, 1839 and Udora Miinster, 1839. We presently know four species of Cretaceous carideans. Martins-Neto & Mezzalira (1991a) found a few specimens of carideans in thè Crato Member of Santana Formation (Lower Cretaceous) of Brazil. The perfect state of preservation of these specimens allowed thè authors to describe thè new genus Beurlenia (family Palaemonidae Rafinesque, 1815) with thè species B. araripensis. Roger (1946) described thè new species Notostomus cretaceus on a sample of five specimens found in thè Santonian (Upper Cretaceous) of Sahel Alma (Lebanon). This species was thè subject of a recent review by Garassino (1994), who ascribed thè species by Roger to thè new genus Odontochelion (family Oplophoridae Dana, 1852). Bravi & Garassino (in press) recently described on a sample of 14 spe¬ cimens of thè Lower Albian (Lower Cretaceous) of Pietraroia (Benevento, S Italy) thè new genus Parvocaris with thè species P. samnitica n.sp. (inde¬ terminate family), while three specimens of thè Middle Albian (Lower Cre- 108 ALESSANDRO GARASSINO taceous) of Petina (Alburni Mounts, Salerno - S Italy) were ascribed to thè new genus Alburnia with thè species A. petinensis n. sp. (family Palaemoni- dae Rafinesque, 1815). Garassino & Ferrari (1992) reported thè presence of only one speci¬ men of caridean in thè Senonian (Upper Cretaceous) ofTrebiciano (Trieste, NE Italy) without ascribing it to a known family, genus and species. Garas¬ sino & Teruzzi (1995) recently reported thè probable presence of a new ca¬ ridean form in thè Upper Hauterivian-Lower Barremian (Lower Creta¬ ceous) ofVernasso (Udine, NE Italy). At present, only four genera of carideans are known in thè Tertiary de¬ posita Four species belong to thè genus Bechleja Housa, 1956, a tipical form of freshwater deposits: B. rostrata Feldmann et alii, 1981 from thè Eocene of thè Green River Formation (Wyoming, USA); B. inopinata Housa, 1956 from thè Oligocene of thè Czechoslovakia; B. bahiaensis (Beurlen, 1950) and B. robusta Martins-Neto & Mezzalira, 1991 from thè Oligocene of Bra- zil (Beurlen, 1950; Housa, 1956, Feldmann et alii, 1981; Martins-Neto & Mezzalira, 1991 b). In thè Miocene deposits of N Caucasus (Russia) thè three genera Pa- laemon Weber, 1795, Pasiphaea Savigny, 1816 and Bannikovia Garassino & Teruzzi, 1996 were described, with thè species P. mortuus Smirnov, 1929, P. mortila Smirnov, 1929 and B. maikopensis Garassino & Teruzzi, 1996 (Smir¬ nov, 1929; Garassino & Teruzzi, 1996) respectively. Patricelli et alii (in press) recently ascribed a sample of over 40 comple¬ te and fragmentary specimens to thè new species Palaemon vesolensis (fa¬ mily Palaemonidae Rafinesque, 1815), found in thè Paleocene deposits of Vesole Mount (Salerno, S Italy). On thè grounds of what described, thè genus Delclosia Rabadà, 1993 with thè species D. martinelli Rabadà, 1993 not only represents thè only fre¬ shwater caridean known to date in thè Cretaceous deposists, but it also re¬ presents one of thè few caridean forms known to date that can be ascribed with certainty to a known family by some characters. In fact, thè review of this species pointed out some characters, partly described by Rabadà (1993) already, such as thè rostrum with 25-30 suprarostral teeth, pereiopods I-II shorter than pereiopods III-V, propodus of pereiopods III-V slightly wider than carpus, and dactylus of pereiopods III-V very short. These characters allow to ascribe thè studied specimens to tha family Atyidae de Haan. 1849, thus confirming thè previous uncertain ascription suggested by Rabadà (1993). At present, thè family Atyidae de Haan, 1849 is known in thè fossil re¬ cord by five genera, one of which of uncertain Cretaceous age, Atyoida Beurlen, 1950, and four of Tertiary age. Caudina Leach, 1816, Atya Milne Edwards, 1837, Atyaephyra de Brito Capello, 1867 and Dugastella Bouvier, 1912. Since thè knownledge on Beurlen's genus is restricted to a few cha¬ racters, it is difficult not only to compare it with thè species D. martinelli Rabadà, 1993, but also to ascribe it with certainty to carideans. At present, four subfamilies belong to thè family Atyidae de Haan, 1849: Atyinae de Haan, 1849, Caridellinae Holthuis, 1986, Paratyinae Holthuis, 1986 and Typhlatyinae Holthuis, 1986 (Holthuis, 1994), all indù- THE MACRURAN DECAPOD CRUSTACEANS OFTHE LOWER CRETACEOUS 1 09 ding freshwater forms. Il is very difficult to ascribe thè Spanish species lo one of these subfamilies, because thè main characters of D. martinelli Ra- badà, 1993, such as thè rostrum with many suprarostral teeth, pereiopods I- II shorter than thè others and thè exopodite with diaeresis, are common to almost all genera belonging to these subfamilies. Moreover, thè lack of mo¬ re specific diagnostic characters, such as thè number of gills and thè presen- ce or absence of exopodite on pereiopods I-III, that can be observed in thè living specimens but not in thè fossi! ones, rules out every opportunity of sure attribution. Infraorder Astacidea Latreille, 1803 Family Astacidae Latreille, 1802 Genus Austropotcìmobiiis Skorikov, 1907 Austropotamobius llopisi (Via, 1971) Figs. 4,5,6,7,8,9,12,13 1971 - Pseudastacus llopisi - Via, p. 608, Figs. 2,2a 1984 - Pseudastacus llopisi - Via, Barale et alii, p. 279 1988 - Pseudastacus llopisi - Via, p. 350, Fig. 339H 1988 - Pseudastacus llopisi - Via, Sanz et ahi, p. 615 1993 - Pseudastacus llopisi - Via, Rabadà, p. 347, Figs. 1,2 Diagnosis. Subrectangular carapace with a deep cervical groove exten- ding into a not very marked antennal groove; long rostrum with one supra¬ rostral tooth in thè proximal third; only one postorbitai tooth at thè base of thè rostrum; chelae of pereiopod I with a marked step in thè proximal part of thè index at thè level of thè articulation with thè dactylus; subrectangular telson, longitudinally subdivided into two parts, with a strong spine in thè lower part of thè lateral margins and with a Y-shaped dorsal carinae System; exopodite with diaeresis. Material. Over 800 complete and fragmentary specimens belong to thè collection of thè Autonomous University of Madrid and to thè private col- lection of Mr. Armando Dfaz-Romeral; 28 almost complete specimens most of which in perfect state of preservation were studied in detail in order to deepen thè analysis on this species. This analysis has allowed to point out not only some characters not observed by Rabadà (1993), but also to de- scribe again other characters badly described in thè originai description. 21 specimens are in dorsal view, 5 in lateral view and 2 in ventral view. LH097, LH101, LH143, LH171, LH191, LH212, LH400, LH401, LH1179, LH2072, LH2097, LH2453, LH2468, LH2513, LH2708, LH2733, LH2894, LH13125, LH13586, LH14011, LH14233. LH14268, LH14295, LH14363, ADR18, ADR82. ADR NC1, ADR NC2 The following specimens were used for thè new description of thè spe¬ cies: LH212, LH401, LH1179, LH2894, LH14268, LH14363, ADR18, ADR82, ADR NC1, ADR NC2 Description. It is a medium-sized astacidean, with strong and strongly tubercolate exoskeleton, 2 to 6 cm in length. 110 ALESSANDRO GARASSINO Fig. 4 - Austropotamobìus llopisi (Via, 1971), carapace reconstruction in dorsal view (A) and in lateral view (B), line drawing. Carapace. The carapace (Fig. 4A), in dorsal view in thè larger part of thè specimens, has a subtrapezoidal shape and it narrows slightly near thè deep ocular incision. The lateral margins are rounded, while thè posterior margin is anteriorly not very arcuate. The carapace (Fig. 4B), in lateral view, has a subrectangular shape and it gets slightly narrower toward thè anterior margin for thè slight curvature of thè ventral margin. The dorsal margin is straight and bends near thè deep cervical groove, it originates in thè median part of thè dorsal margin and it slightly degrades toward thè antennal re- gion, with a not very marked antennal groove. The posterior margin, strengthened by a thin marginai ridge, is sinuous, with a slight concavity in thè lower third. The dorsal margin extends into a long rostrum, with a poin- ted distai extremity and with only one suprarostral tooth in thè distai part. The subrostral teeth are lacking. The rostrum is strengthened by a toothless thin median carina. A strong forwards protruded postorbitai tooth is pre- sent at thè base of thè rostrum. The narrow and deep ocular incision ends with a strong antennal spine. The pterygostomial angle is not very pronoun- ced. The branchiocardiac, postcervical and hepatic grooves are lacking. The carapace surface is strongly tubercolate. Abdomen. The somites, strengthened by a thin longitudinal median ca¬ rina, are of even length, are subrectangular in outline and narrow caudally. The dorsal surface of thè somites is slightly tubercolate. Somite VI has two strong tubercles at thè level of thè articulation margin with thè telson. The tail fan (Fig. 5) is well preserved in most specimens. The telson is subrectan¬ gular in shape, has a rounded distai extremity and is crossed by a Y-shaped thin dorsal carinae System: thè longitudinal median carina extends along thè Fig. 5 - Austropotamobius llopisi (Via, 1971), tail fan reconstruction, line drawing.