XX (2S7\IS.2>) 



Bull. nat. Hist. Mus. Lond. (Zool.) 68(2): 123-130 



Issued 28 November 2002 



The skull of the Uropeltinae (Reptilia, 

 Serpentes), with special reference to the otico- 

 occipital region 



OLIVIER RIEPPEL 



Department of Geology, The Field Museum. 1 400 S Lake Shore Drive, Chicago, IL 60605-2496, U.S.A. e-mail: 

 rieppel@fieldmuse.um. org 



HUSSAM ZAHER 



Universidade de Sao Paulo, Institute de Biociencias, Departamento de Zoologia, Rua do Matao, Travessa 14, 

 Cidade Universitaria, 05508-900, Sao Paulo, SP, Brazil 



SYNOPSIS. The skull anatomy ot'uropeltines is reviewed, and new data is presented on the highly derived otico-occipital region. 

 A phylogenetic analysis of uropeltine interrelationships using parsimony is performed using characters derived from skull 

 structure. The basal position of the genus Melanophidium is confirmed; Pseudotyphlops is a relatively derived uropeltine. in spite 

 of its relatively large size. The monophyly of the genera Melanophidium and Rhinophis requires further testing. 



INTRODUCTION 



MATERIAL EXAMINED 



Uropeltinae (Nopcsa 1923. The name is here used as by Kluge 1991, 

 Fig. 4; see also Cundall et al. 1993) remain an enigmatic group of 

 basal alethinophidian snakes. This is largely due to their burrowing 

 habits and restricted distribution, and the consequent scarcity of 

 material available in public repositories. We have studied the 

 uropeltine skulls from the collections of The Natural History Mu- 

 seum, London, which permitted us to review the highly derived skull 

 structure in this monophyletic clade of snakes. 



The first detailed description of a uropeltine skull was given by 

 Baumeister (1908) in a monograph on the genus Rhinophis. Peculi- 

 arities of the cranio-vertebral joint in the group were dealt with by 

 Williams ( 1 959), Underwood ( 1 967), and Hoff stetter & Gasc ( 1 969). 

 Some aspects of the skull of uropeltines were described by Rieppel 

 (1977. 1978, 1983), Bellairs & Kamal (1981), and Wever (1978), 

 but none of these studies addressed details of the morphology of the 

 otico-occipital complex. The lower jaw of uropeltines was described 

 by Rieppel & Zaher (2000). In their detailed analysis of the cranial 

 anatomy and phylogenetic relationships of Anomochilus, Cundall & 

 Rossman (1993), and Cundall et al., (1993), comment on various 

 aspects of the skull structure of uropeltines, and their functional as 

 well as phylogenetic significance. In particular. Cundall & Rossman 

 (1993; see also Cundall & Greene 2000) recognized a fundamen- 

 tally different design of skull adaptation to burrowing habits in 

 scolecophidians and uropeltines (Fig. 1 ). The phylogenetic relation- 

 ships of uropeltines within snakes were discussed in cladistic terms 

 by Cundall et al. (1993), Scanlon & Lee (2000), andTchernov etal, 

 (2000). Only one study has appeared so far that dealt with uropeltine 

 interrelationships, based on microcomplement fixation techniques 

 (Cadle et al. 1990). In this paper, we review the skull anatomy of 

 uropeltines, adding new detail to previous descriptions (Rieppel 

 1977, 1978) and providing new data on the detailed morphology of 

 the otico-occipital complex. These morphological characters are 

 used in a phylogenetic analysis of uropeltine interrelationships, 

 which will be compared to the results obtained by Cadle et al. 

 (1990). This study is presented in honor of Dr. Garth Underwood, 

 who more than 20 years ago introduced the senior author to the study 

 of the skull of 'henophidian' snakes. 



The present study is based on the investigation of the skull of the 

 following taxa (generic names used in the manuscript refer only to 

 the specimens here listed), arranged as outgroup taxa and in-group 

 (uropeltine) taxa. 



Institutional abbreviations 



BMNH, British Museum (Natural History), now The Natural His- 

 tory Museum; FMNH. Field Museum of Natural History, now The 

 Field Museum. 



Outgroup taxa: Anilius scytale (FMNH 35683); Cylindrophis 

 maculatus (BMNH 1930.5.8.48); Cylindrophis ruffits (FMNH 

 179033); Boa constrictor (FMNH 22435, 22438); Calabaria 

 reinhardtii (FMNH 31372); Candoia aspera (FMNH 13915); 

 Candoia h. australis (FMNH 22997); Lichanura roseofusca (FMNH 

 31565); Python molurus (FMNH 223198); Tropidophis pardalis 

 (FMNH 233). 



In-group taxa: Melanophidium punch/turn (BMNH 1930.5.8.119); 

 Melanophidium wynaudense (BMNH 1930.5.8.124-125); Platy- 

 plecturus madurensis (BMNH 1930.5.8.111); Plecturus perroteti 

 (BMNH 1930.5.8.105); Pseudotyphlops philippinus (BMNH 

 1978.1092); Rhinophis drummondhayi (BMNH 1930.5.8.67-68); 

 Rhinophis sanguineus (BMNH 1930.5.8.59); Teretrurus rhodo- 

 gaster (BMNH 1930.5.8.98); Uropeltis woodmansoni (BMNH 

 1930.5.8.73-74); 



Abbreviations used in the figures 



ang, angular; bo, basioccipital; com, compound bone; d, dentary; 

 ec, ectopterygoid; f, frontal; Is, laterosphenoid; m, maxilla; n, nasal; 

 oc, otic capsule; op-eo, opisthotic-exoccipital; p, parietal; pi, pala- 

 tine; pm, premaxilla; po.vc, posterior opening of Vidian canal; prf, 

 prefrontal; pro, prootic; pro.c, prootic canal; pro.r, preorbital ridge; 

 pt, pterygoid; q, quadrate; sm, septomaxilla; so, supraoccipital; sp, 

 splenial; tr.f.r, transverse frontal ridge; v, vomer; II, optic foramen; 

 V,, trigeminal foramen (maxillary branch); V 3 , trigeminal foramen 

 (mandibular branch); VII, facialis foramen; X, jugular foramen; 

 XII, hypoglossal foramen. 



© The Natural History Museum, 2002 



