Contributions to Zoology, 72 (2-3) 101-104 (2003) SPB Academic Publishing bv, The Hague Decapod crustaceans from the Oligocene of the Ligure Piemontese Basin, northern Italy Antonio De Angeli¹ & Sergio Marangon² 'Associazione Amici del Museo civico G. Zannato Piazza Marconi 15, 1-36075 Montecchio Maggiore 2 (Vicenza), Italy; c/o Via Anemone 8, 1-20090 Segrate (Milano), Italy Keywords: Crustacea, Decapoda, Oligocene, Italy M. Abstract species postulosus. Subsequently, new material housed in the collections of the Museo civico at Lithologically, the decapod-bearing levels of Rupelian (Oligo- Ovada and the Museo regionale di Scienze naturali cene) in the Ligure Piemontese Basin, are characterizedby age at Torino, was studied by Allasinaz (1987), who an alternation of greyish blue marls with nodular elements and described'Calappilia mainii Alassinaz, C. vicetina silt-rich, occasionally sandy, marls. The fossil studied for the and Portunus Fabiani, Calappa sp. monspeliensis present note have been collected mainly from pebblesor nodules Milne The additions in- which (A. Edwards). most recent were eroded out of the higher levels exposed of this clude rostratus & De sedimentary complex, referred to as the ‘Formazione di Mol- Cherpiocarcinus Marangon are’. These levels overli the ‘Formazioni continentali delle Brecce Angeli (Fig. 1/1) and Calappilia verrucosa A. Milne di studied al. Costa Cravara e Charrier et (1964) Pianfolco’, by Edwards (Fig. 1/2) from Cherpione (Pianfolco) (see and dated as Early Rupelian. The levels yielding brachyuran Marangon & De Angeli, 1997; De Angeli & Maran- fossils were attributed by Allasinaz (1987) to the transition bet- in Paralbunea gon, press) and galantensis from ween the ‘Formazione di Molare’ and the overlying ‘Marne di Contra Galanti (Cassinelle) (see De Angeli & Maran- Rigoroso’, and by Bianco (1985) and Balossino& Bianco (1986) to the biozone of the foraminifer Operculina complanata (De- gon, 2001). france). The faunas Introduction Currently, our knowledge of the crab fauna from Studies of crustaceans of the Pie- Piemontese decapod Ligure the Ligure Basin enables a compari- montese Basin started with Sismonda (1846, 1861), son with Oligocene faunas from elsewhere in south- who recorded the occurrence of in the brachyurans ern Europe. The genus Calappilia is represented Miocene of Torino hill. Later followed Michelotti by three species: C. verrucosa correlates with the (•861), Ristori and Crema who (1886, 1888) (1895), Rupclian of Biarritz (France) and C. vicetina, con- described additional discoveries. For levels exposed fined to the Oligocene of Vicenza (NE Italy) where at Sassello, Santa Giustina, Fornaci and Ris- Dego, coeval deposits of lagoonal origin are known which tori (1889) recorded the Pa- following species: contain several Coeloma vigil and various portunid laeocarpilius macrochelus (Desmarest), Portunus species. convexus Coeloma A. Milne Edwards, Portunus (Ristori), vigil convexus (Fig. 1/3) was based on the Panina R. aldrovandi (Ron- speciosa (von Munster), type specimen only, and external mould of a cara- zani)?, Callianassa canavari Ristori, of of which fragments pace, wax and clay casts were produced. Hoploparia some claws to the sp., assignable gen- This means that the species is comparatively poorly era Eriphia, Callianassa and Grapsus, , Pagurus, known, not all of the istinguishing features having and established the with genus Mursiopsis, type been preserved. Although it is not our intention in Downloaded from Brill.com09/26/2021 12:42:37AM via free access 102 A. De Angeli & S. Marangon - Crabsfrom the Oligocene ofLiguria I. Crabs from the 1 - & De reconstruction Fig. Ligure Piemontese Basin: Cherpiocarcinus rostratus Marangon Angeli, carapace - 2 - A. Milne reconstruction 3 Portunus (x 1.8); Calappilia verrucosa Edwards, carapace (x2.4); convexus (Ristori), carapace and in dorsal view and reconstruction (0.9); 4 - Zygopa galantensis (De Angeli & Marangon), carapace pereiopod I (holotype) (a) carapace reconstruction (b) (x3.4). the available time. The of present note to discuss this species in detail, samples at that presence P. do wish the in the of the Pie- we to note presence of a curved spine monspeliensis Rupelian Ligure on both sides of the Basin is Allasinaz noted that posterior carapace margin. montese uncertain; Allasinaz (1987) did not observe these spines in samples attributed to that species might belong to Downloaded from Brill.com09/26/2021 12:42:37AM via free access - Contributions to Zoology, 72 (2-3) 2003 103 it Ranina Z. or to a subspecies similar, ancestral species. (Florida, Netherlands Antilles, Surinam) and speciosa occurs in the Cenozoic of Germany (be- nortoni Serene & Umali (Philippines and New Cale- tween Osnabriick and Kassel) and in the Lower donia). In the world wide review of fossil and Recent Miocene of Bassano del Grappa (Vicenza) and of Albuneidae and Blepharipodidae, Boyko (2002) Monfumo this illustrations (Treviso). In carapace shape, spe- presented detailed descriptions and of cies is closely similar to R. bouilleana A. Milne all known species and clear diagnoses of families Edwards from the of and He also discussed the features of.Albunea Rupelian Biarritz; on orna- genera. ment, these species may be distinguished. Palaeo- lutetiana Beschin & De Angeli from the Middle macrochelus is distributed of it in the carpilius widely geo- Eocene Vicenza, including new genus graphically, having been recorded from France to Italialbunea. In view of this, we think it advisable in rocks of Eocene and here list of and of the India, Oligocene age. to present a genera species Ristori (1889) erected the genus Mursiopsis, but superfamily Hippoidea from the fossil record: failed to present a detailed diagnosis, which he compared with Mursia and Calappilia. Glaessner Superfamily Hippoidea Latreille (1969) listed Ristori’s taxon, but did not note de- Family Blepharipodidae Boyko fining characteristics. Allasinaz (1987) was the first Genus Lophomastix Benedict to point out the affinities of Mursiopsis, distinguish- L. antique Schweitzer & Boyko (Eocene, ing it from Mursia on the basis of the more marked Washington, USA) trilobed of the and the different nature carapace form and disposition of the ornament and from Family Albuneidae Weber Calappilia on the basis of convex post-lateral bor- Genus Albunea Weber ders and the presence of a few short teeth. Cara- A. asymmetrica (Muller) (Miocene, Hungary) pace shape in Cherpiocarcinus restratus did not A. hahnae Blow & Manning (Middle Eocene, provide data for comparisons with extant taxa. Af- South Carolina, USA) cuisiana & De finities were noted with the Necrocarcininae, in A. Beschin Angeli (Lower- particular with Orithopsis bonneyi Carter from the Middle Eocene, Italy) Cenomanian of England. Paralbunea galantensis A. sp. (see Morris, 1993) (Pleistocene, Jamaica) was based on a single specimen from the Rupelian Genus Italialbunea Boyko of Galanti (Cassinelle, Alessandria). This species I. lutetiana (Beschin & De Angeli) (Middle has a carapace which is wider than long, with a Eocene, Italy) narrow front, very small rostrum (almost absent), Genus Praealbunea Fraaije the a poorly developed lateral spine on ocular cen- P. rickorum Fraaije (Maastrichtian, the Nether- ter, a sinuous anterior margin, lacking spines, and lands) with a setal field Genus Holthuis present as two narrow, oblique Zygopa bands behind the ocular sinus. The dorsal surface Z. galantensis (De Angeli & Marangon) (Early has few transverse, grained furrows, the cervical Oligocene, Italy) furrow is deepened medially, and with a divergent branchial-cardiac correlations with elsewhere groove, a very concave posterior For occurrences in margin, and pereiopod 1 ofcomparable dimensions, Europe, the brachuyrans from the Figure Piemontese with in the carpus with rounded margin, lacking a dorsal Basin, particular genera Coeloma, Palaeo- These crest. features confirm assignment to the genus carpilius, Calappilia, Ranina and Portunus are all Paralbunea. distributed widely geographically and this may be A re-examination and better of the due to a better preparation genetic adaptation to cope with carapace margins of the type specimen has now adverse conditions, related to environment rather revealed a hepatic spine, and this has led to a new than to climate. reconstruction the Other crustaceans (Fig. 1/4), and a transfer to ge- appear restricted to certain lev- nus Zygopa (De Angeli & Marangon, in press). This els. Endemic in the Figure Piemontese Basin, and genus contains the extant Z. michaelis Holthuis occurring in lagoonal strata, characterized by a high Downloaded from Brill.com09/26/2021 12:42:37AM via free access 104 A. De Angeli & S. Marangon - Crabs from the Oligocene ofLiguria supply offreshwater and several plant remains car- De Angeli A, Marangon S. in press. Contribute alia cono- scenza dei decapodi oligocenici del Bacino Ligure Pie- ried by numerous streams, are Mursiopsis postulo- montese (Italia settentrionale). Atti Soc. it. Sci. not Mus. sus, Z. galantensis and Cherpiocarcinus rostratus. civ. St. nat. Milano Glaessncr M.F. 1969. Decapoda. In: Moore RC, Teichert C (eds). Treatise on Invertebrate Paleontology, R Arthropoda _ References (4)2: R339-533, 626-628. Boulder/Lawrence: Geological Society of America/University of Kansas Press. Marangon S, De Angcli A. 1997. Cherpiocarcinus, nuovo Miasma/ A. 1987. Brachyura Decapoda oligocenici (Rupe- di brachiuro del Bacino genere (Decapoda) dell’Oligocene del Bacino Piemontese. Mus. Sci. liano) Ligure