Tantilla atriceps (Gunther) 

 Homalocranium atriceps GunthQT, 1895: 146. 



Syntypes.— British Museum of Natural History (BMNH) 1946.1.8.81-82 (original 

 numbers 89.7,3.36-37, respectively), both males, obtained in 1889 from W. Taylor. 



Type-locality. — "Nuevo Leon, Mexico." 



Distribution. — Low, moderate, and intermediate elevations in southeastern Chihuahua, 

 southern Coahuila, northwestern Nuevo Leon, northern San Luis Potosi, northern and eastern 

 Durango, and northeastern Zacatecas, Mexico, with apparently disjunct populations in 

 Tamaulipas, Mexico, and southern Texas 



Systematic references. — Cole and Hardy (1981, 1983a). 



Remarks. — Cole and Hardy (1981) demonstrated that T. atriceps and T. hobartsmithi are 

 sibling species, differing from one another in the structure of the hemipenis. Other features 

 used to distinguish between these two species (number of postoculars, contact or lack thereof 

 between mental and anterior chinshields) do not consistently do so (Robert G. Webb, in litt.). 

 In addition, some specimens of T. nigriceps cannot be distinguished convincingly from these 

 two sibiling species in areas of sympatry (Cole and Hardy, 1981). Thus, details of the 

 systematic and distributional relationships among these three species remain to be elucidated. 



Tantilla bairdi Stuart 

 Tantilla bairdi Stuart, 1941: 1. 



Holotype. — University of Michigan Museum of Zoology (UMMZ) 89223, adult female, 

 collected by L. C. Stuart, 17 May 1940. 



Type-locality. — Two km NE Finca Chichen (10 straight line km S Coban) on Chameico 

 trail, ca. 1550 m, Depto. Alta Verapaz, Guatemala. 



Distribution. — Moderate and intermediate elevations (1524-1550 m) of the Caribbean 

 versant of central Guatemala. 



Systematic references. —(Wilson, 1982b, 1985a, 1985e). 



Remarks. — A second specimen of this taxon was reported by Wilson (1985a). 



Tantilla bocourti (Gunther) 

 Homalocraniiim bocourti Gunther, 1895: 149 (see Remarks). 

 Tantilla bocourti bocourti: Smith and Laufe, 1945: 348. 



Lectotype.— British Museum of Natural History (BMNH) 1946.1.8.70 [formerly BMNH 

 94.10.2.1], obtained on exchange from Museum National d'Histoire Naturelle, Paris (formerly 

 MNHNP 3694), aduh male, collected by Dr. Alfredo Duges, date of collection unknown (see 

 Remarks). 



Type-locality. — "Guanajuato, Mexico," restricted to city of Guanajuato by Smith and 

 Taylor (1950). 



Distribution. — Low to intermediate elevations of the Pacific versant from northeastern 

 Sinaloa southeastern to Guanajuato and Puebla, Mexico (including the Tres Marias Islands), 

 and southward to central Guerrero, Mexico; also on the Atlantic versant in Hidalgo, Puebla, 

 and central Veracruz, Mexico. 



