Ceratophrys (Lynch, 1971)

Nicoli, Laura, 2019, The fossil record of Ceratophrys Wied-Neuwied (Anura: Ceratophryidae): a revision and update of fossil South American horned frogs, Zootaxa 4658 (1), pp. 37-68 : 59-60

Ceratophrys sp. (MLP 96.V.18.12) from the archeological locality Fortín Nechochea, Buenos Aires, Argentina ( Mercadal de Barrio & Barrio 2002)

An incomplete skull (MLP 96.V.18.12) from the archeological locality Fortín Nechochea ( Fig. 1 , locality 5), in the Partido of General La Madrid in the province of Buenos Aires, Argentina, was referred Ceratophrys sp. by Mercadal de Barrio & Barrio (2002). This sequence was deposited during the middle Holocene ( Prado & Alberdi 1999, and references therein).

Osteological features. MLP 96.V.18.12 ( Fig. 6L, M ) is an incomplete skull that lacks both premaxillae and most of the maxillae. The preserved regions generally resemble the skulls of Ceratophrys . Cranial crests are absent. Only the anterior region of the left maxilla is preserved; the bone lacks a distinct pars palatina, and bears a long socket that presumably articulated the maxillary process of the premaxilla. Teeth are incompletely preserved. The squamosal otic plates are too poorly preserved to describe their original shape or extension; however, a well-developed postorbital fenestrae is evident ( Fig. 6L ). The poor preservation of the anterior part of the skull obviates description of the vomers and neopalatines.

Remarks. MLP 96.V.18.12 possesses all the possible synapomorphies of Ceratophryidae (exostosis, maxillasquamosal contact, parieto-squamosal arch, expanded squamosal otic ramus overlapping prootic, absence of pars palatina on anterior maxilla) and Ceratophrys (robust, bar-shaped maxillary processes of nasals, postorbital fenestra, premaxilla with long maxillary processes). Thus, the referral of this material to Ceratophrys is well supported, but the skull is too incomplete to evaluate characters for its specific identity.

Figures

FIGURE 1. Distributional map of extant and fossil Ceratophrys. The phylogeny of the extant species of Ceratophyrs were proposed by Faivovich et al.(2014). The numbers in circles represent the fossiliferous localities mentioned in the article: 1, Arroyo Chasicó; 2, Arroyo Tapalqué; 3, Conchillas; 4, Farola Monte Hermoso; 5, Fortín Necochea; 6, Lagoa Santa; 7, Laguna de Los Tres Reyes; 8, Mar del Plata and Miramar cities; 9, Ñuapua; 10, Olivos; 11, Puerta de Corral Quemado; 12, Quehué; 13, San Antonio and Paso Alsina; 14, Tarija. Black circles: localities where the presence of Ceratophrys was confirmed; white circles: the presence of Ceratophrys remains unconfirmed. The distributions of the extant species of Ceratophrys are represented by areas that approximately include all the reported records for each species; the distribution of most species, however, is not well known. Distributions are based on Lynch (1982) with corrections and additions from Barrio-Amorós 2004; Barrio 1980; Langone 1995; Maciel et al. 2013; Maneyro & Langone 2001; Ortiz et al. 2013; Peters 1967; Rivero 1961; Stuart et al. 2008.

FIGURE 6. Quaternary fossils attributed to Ceratophrys. A, fossil columella (MLP 86.VIII.1.5) from Laguna Los Tres Reyes Locality, province of Buenos Aires, Argentina, attributed Ceratophrys cf. ornata by Perí (1993). B, columella of C. cranwelli (FML 5475). C–G, two incomplete skulls (C–E) and a premaxilla (F, G) from Ñuapua, Bolivia, attributed to Ceratophrys cf. ornata by Vergnaud-Grazzini (1968). H–K, fossils from the Arroyo Tapalqué locality, Buenos Aires, Argentina, listed as Ceratophrys sp. by Mercadal de Barrio & Barrio (2002); H–J, MLP 86.III.25.150: squamosal (H) and right maxilla (I, J); K, MLP 86.III.25.151: frontoparietals. A,C, H, K, dorsal views; B, ventral views; D, J, lingual views; E, I, labial views. Abbreviations: as, angulosplenial; d, dentary; fp, frontoparietal; pp, premaxillary palatine process; ppa, discrete pars palatina absent; lc, lateral crest; mk, mentomeckelian; mop, material of preparation; mp, maxillary process of nasal; mpp, maxillary process ofpremaxilla; mps, socket that would receive the maxillary process of premaxilla; ncs, socket that would have received the ossification of the nasal cartilages; oc, occipital condyle; otc, otic capsule; pas, socket that would have received the ossifications of the planumantorbitale; pf, pars facialis; pof, space delimiting by the showed bone that corresponds to the postorbital fenestra; pp, pars palatina; ppa, discrete pars palatina absent; psa, portion of the bone that forms the parieto-squamosal arch; psf, parasphenoid; pt, pterygoid; ptp, pterygoid process; qj, quadratojugal; th, teeth; slw, squamosal lateral world; sop, squamosal otic plate; sf, space delimiting by the showed bone that corresponds to the subtemporal fenestra; v, vomer; vr, squamosal ventral ramus; zr, squamosal zygomatic ramus. Scale bar is 5 mm.