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Rev. Biol. Trop., 49(2): 715-764, 2001 www.ucr.ac.cr www.ots.ac.cr www.ots.duke.edu ATaxonomic Reevaluation of Phrynops (Testudines: Chelidae) with the description of two new genera and a new species of Batrachemys. William P. McCord1, Mehdi Joseph-Ouni2 and William W. Lamar3 1 East Fishkill Animal Hospital, Hopewell Junction, New York 12533 USA; Fax: 845-221-2570; e-mail: [email protected] 2 EO Wildlife Conservation and Artistry; Brooklyn, New York 11228 USA; www.eoartistry.com; e-mail: [email protected] 3 College of Sciences, University of Texas at Tyler, 3900 University Blvd. Tyler, Texas, 75799, USA; Fax: 903-597- 5131; email:[email protected] Abstract: Relationships among turtle species loosely categorized within the South American genus Phrynops are explored. Three once recognized genera (Batrachemys, Mesoclemmys and Phrynops) that were demoted to sub- genera, and then synonymized with Phrynops, are demonstrated to warrant full recognition based on morphomet- ric analysis, skull osteology, and mitochondrial and nuclear gene sequencing. Mesoclemmys is resurrected from the synonymy of Phrynops as a monotypic genus including M. gibba. The genus Rhinemys, previously a synonym of Phrynops, is resurrected for the species R. rufipes. Ranacephala gen. nov. is described to include the species R. hogei. The genus Batrachemys is resurrected from the synonymy of Phrynops and includes B. dahli, B. nasuta, B. raniceps, B. tuberculata, and B. zuliae. The taxon vanderhaegei is placed in Bufocephala gen. nov. The genus Phrynops is redefined to include the taxa P. geoffroanus, P. hilarii, P. tuberosus, and P. williamsi. Cladistic analy- sis of morphological data supports this taxonomy. A new species of Batrachemys is described from the western Amazon region, and is distinguished by having facial markings in juveniles, a relatively wide head, and a flattened shell. The new species, B. heliostemma sp. nov., is sympatric with and most similar to the recently resurrected form Batrachemys raniceps in the upper Amazonian region of Peru and adjacent Brazil, Ecuador, Venezuela, and Colombia. Lastly, morphometric data from living and museum specimens of all species of Batrachemys are pre- sented. Key words: Turtles, Pleurodira, chelid, genera, South America, toadhead, Iquitos, systematics. “Turbulent” well describes the taxonomic We herein give a chronological account- history of the New World Pleurodira. Phrynops ing of the taxonomic history specifically of the (sensu lato) is a chelid genus endemic to South turtles listed under Phrynops (sensu lato). America that includes the toadheads, a group Starting with his monograph of the Testudines, of species whose inter-relationships have been Schweigger (1812) described the first three uncertain. With the exception of the Phrynops toadheads, Emys geoffroana, Emys nasuta and geoffroanus complex, most species are poorly Emys gibba. Noticing clear differences known, rare, or limited in distribution (Iverson, between the South American side-necked 1992). The toadheads (first defined by Gray, species in the genus Emys and their congeners, 1855, for the “Toad-Headed Hydraspis, H. the Australian side-necked turtles, Fitzinger raniceps sp. nov.”) have a sinuous and per- (1826), advised by Oppel, erected the new plexing history. Multiple synonyms and poorly genus Chelodina for the Australian forms, with recorded field data abound in the literature Emys longicollis of eastern Australia as the (i.e., Wermuth and Mertens 1977). generotype. 716 REVISTA DE BIOLOGÍA TROPICAL Apparently unaware of Fitzinger’s work, Wagler’s work, that genus name was used erro- Bell (1828) proposed the genus Hydraspis to neously (e.g., Siebenrock 1904, 1909; include all side-necked turtles. The generotype Luederwaldt 1926) for many of the South was also Testudo (Emys) longicollis, and it was American chelids, including the toadheads as diagnosed as having a depressed head and well as taxa currently assigned to Platemys and body; projecting nose and narrow nostrils; a Acanthochelys. Since Hydraspis was clearly a long and “extensile” neck; and an anteriorly junior synonym of Chelodina (same gen- broad first vertebral scute. erotype; Chelodina has precedence), Stejneger In 1830, Wagler described the monotypic (1909) again corrected the problem by syn- genus Phrynops for the Brazilian species Emys onymizing Hydraspis under Chelodina. geoffroana Schweigger (1812). He also creat- Like Boulenger, Stejneger (1909) also ed the genus Rhinemys to subsume four other observed that Schweigger’s (1812) Emys species then assigned to Emys: E. rufipes Spix nasuta was distinct from the species then (1824), E. gibba Schweigger (1812), E. nasuta included in Phrynops. Since E. rufipes was Schweigger (1812) and E. radiolata Mikan the generotype for Rhinemys, and Rhinemys (1820). had been synonymized with Phrynops by Realizing that Wagler had not designated Gray (1844), E. nasuta required a new nomi- a generotype for Rhinemys, Fitzinger (1843) nal genus. Thus, Stejneger (1909) proposed specifically chose the species E. rufipes as the the genus Batrachemys with B. nasuta as the type. Emys rufipes Spix (1824) was not the generotype, although he provided no descrip- oldest species in the genus Rhinemys, being tive characteristics. preceded by E. nasuta Schweigger (1812:298) Stejneger’s (1909) revision was apparent- and E. gibba Schweigger (1812:299). But, as ly unavailable to Siebenrock (1909), who still “first reviewer,” Fitzinger had the right to recognized Hydraspis as the genus for South choose whichever of Wagler’s four Rhinemys American toadheads of the Phrynops geof- species he deemed appropriate. It is possible froanus complex (P. geoffroanus, P. tuberosus, that his decision was based on the fact that E. P. rufipes and P. wagleri) and used the generic rufipes has the most prominent nose of the designation of Rhinemys for the Batrachemys toadheads then being considered (Rhinemys nasuta complex (at that time, using specimens translates to “nose-turtle”). of “R. nasuta” from Suriname to Bolivia and Gray (1844) believed that R. rufipes and various localities of the upper Amazon region). P. geoffroyana (=P. geoffroanus) were con- By the mid-twentieth century, the three generic. Since international nomenclatorial genera – Batrachemys, Phrynops and rules permit the first reviser to select the valid Mesoclemmys, were still in use. The monotyp- genus in the case of two generic names pro- ic genus Mesoclemmys held M. gibba; posed on the same date, despite the fact that Phrynops included P. geoffroanus geoffroanus, Rhinemys appeared prior to Phrynops (Wagler P. g. tuberosus, P. g. hilarii and P. rufipes; and 1830: 134 vs. 135) in the same publication, Batrachemys included B. nasuta, B. tubercula- Gray synonymized Rhinemys under Phrynops. ta and B. dahli (Wermuth and Mertens, 1961; Further examination of toadheads by Gray Pritchard, 1967). (1873a) led him to describe the monotypic In their description of a new toadhead genus Mesoclemmys for the species Rhinemys from Bolívar, Colombia, Zangerl and Medem gibba. This genus was considered valid until (1958) questioned the need for three genera of assigned subgeneric status by Zangerl and toadheads. They suggested that the traits sup- Medem (1958). posedly diagnostic of the three genera were in Subsequent to Bell’s (1828) description of fact substantial enough only for subgeneric Hydraspis, during the nineteenth and twentieth division under the priority (oldest) name centuries, and despite both Gray’s and Phrynops (see also Lescure and Fretey 1975). INTERNATIONAL JOURNAL OF TROPICAL BIOLOGY AND CONSERVATION 717 Their decision was based heavily on the relationships (but see Shaffer et al. 1997, and unpublished work of Williams and Vanzolini. Gaffney and Meylan 1988, for other details on Bour (1973; see also Bour and Pauler, chelid phylogeny). Wermuth and Mertens 1987) considered the subgenera so poorly (1977) expressed concern regarding the recog- diagnosed as to warrant full synonymy under nition of subgenera within Phrynops, noting the Phrynops, an arrangement followed by unstable subgeneric differences, such as the Vanzolini et al.. (1980) and Rhodin et al.. variable neural bone arrangements. (1982). Ernst and Barbour (1989) mentioned Although inconclusive, the monophyly of the subgenera, but followed Bour (1973) in not the genus Phrynops (sensu lato) seemed to be recognizing them. However, some authors supported by the “early” genetic data of Frair (e.g., Winokur and Legler 1974; Freiberg (1980, 1982) and Reed et al. (1991). Using mito- 1975; Albrecht 1976; Gaffney 1979; Winokur chondrial DNA sequencing, morphological and 1982; Lema 1994; and Cabrera 1998) retained paleontological approaches, Schaffer et al. Batrachemys as a full genus in their works. (1997) provided hypotheses of chelonian phy- Pritchard (1967, 1979) and Pritchard and logeny that show both the family Chelidae and Trebbau (1984) recognized the three contro- the genus Phrynops (sensu lato) to be mono- versial subgenera. They diagnosed the sub- phyletic. However, in an effort to resolve the genus Mesoclemmys largely on morphological conflicting taxonomic proposals, Seddon et al. characters: small chin barbels (=barbels); the (1997) sequenced 411 mitochondrial 12S rRNA presence of zero to five often discontiguous nucleotides of 16 representative species within neural bones, never contacting the nuchal the 11 recognized chelid genera. Analysis using (proneural) bone; less than thirty cm in shell parsimony and neighbor-joining algorithms length;