Proctoporus, TSCHUDI

Doan, Tiffany M. & Castoe, Todd A., 2005, Phylogenetic taxonomy of the Cercosaurini (Squamata: Gymnophthalmidae), with new genera for species of Neusticurus and Proctoporus, Zoological Journal of the Linnean Society 143 (3), pp. 405-416 : 412

PROCTOPORUS TSCHUDI

Type species: Proctoporus pachyurus Tschudi, 1845: 161 .

Proctoporus pachyurus group: Uzzell, 1970: 4.

Definition: Tongue with imbricate, scalelike papillae. Head scales smooth without striations or rugosities: single frontonasal, frontal, and interparietal; paired frontoparietals and parietals; prefrontals absent; nostril pierced in a single nasal; nasals not in contact. Eyelids developed, lower with an undivided translucent disc. Posterior gulars squarish. Limbs pentadactyl; digits clawed. Dorsal scales quadrangular, elongate, keeled, juxtaposed, forming transverse series only. Ventrals large, smooth, quadrangular, juxtaposed, forming regular longitudinal and transverse series. Femoral pores present in males, sometimes absent in females; preanal pores absent in both sexes. Tail cylindrical.

Diagnosis: Proctoporus differs from members of subfamily Alopoglossinae by having its tongue covered in imbricate, scale-like papillae instead of oblique plicae ( Harris, 1994), from Gymnophthalminae by having moveable eyelids, from Rhachisaurinae by having external ear openings and from Ecpelopinae by lacking prefrontal scales. Within Cercosaurinae (sensu Castoe et al., 2004) , Proctoporus differs from all genera except Pholidobolus , Riama , and Petracola by lacking prefrontal scales. It differs from Riama by having an entire palpebral eye disc, from Petracola by having keeled dorsal scales and from Pholidobolus by having juxtaposed dorsal scales.

Content: Proctoporus s.s. includes five species ( Table 1 ).

Distribution: Proctoporus occurs in the Andes of the Peruvian departments of Apurimac, Ayacucho, Cusco, Junín, and Puno, and the Bolivian departments of Cochabamba, La Paz, and Santa Cruz.

Remarks: Recent field-work recovered specimens and tissues (for molecular analysis) of P. pachyurus , for which no such material had previously been available. Preliminary molecular sampling using the mitochondrial gene ND4 revealed that Proctoporus s.s. as described here is a monophyletic group that includes P. pachyurus and an undescribed lineage (T. M. Doan, T. A. Castoe, & Arizábal, unpubl. data).

Based on phylogenetic analyses of morphological characters, Doan (2003a) stated that, due to the lack of monophyly of the P. pachyurus group, the character of an undivided palpebral disc should not be considered a synapomorphy and was likely a pleisiomorphic character. In contrast to that study, molecular evidence strongly supports the monophyly of this group and we believe that the undivided palpebral disc is a valid synapomorphy for the genus Proctoporus s.s., despite the fact that a single specimen of P. bolivianus (AMNH R-150695) was found with a divided palpebral disc ( Wiens & Servedio, 2000).

Although Tschudi (1845) did not provide an etymology for the name Proctoporus , the name presumably refers to the preanal pores that he reports for the type species P. pachyurus . However, neither the type species, nor any other members of the genus Proctoporus s.s. have preanal pores ( Uzzell, 1973; pers. obs.). Thus, the name erroneously describes a character that these species do not possess.