Cerrophidion

Robert C. Jadin, Eric N. Smith & Jonathan A. Campbell, 2011, Unravelling a tangle of Mexican serpents: a systematic, Zoological Journal of the Linnean Society 163, pp. 943-958 : 953

CERROPHIDION CAMPBELL & LAMAR, 1992

Type species: Bothriechis godmanni Günther, 1863 , by subsequent designation of Campbell & Lamar (1992).

Etymology: The generic name comes from the Spanish cerro, meaning mountain, an allusion to the habitat, and the Greek ophidion, meaning small snake (Campbell & Lamar, 1992).

Content: The genus Cerrophidion contains three species: Cerrophidion godmani , Cerrophidion petlalcalensis , and Cerrophidion tzotzilorum . These species occur in pine-oak and cloud forests from Veracruz (Mexico) southward through the highlands of Central America to Panama (Campbell, 1985; Campbell & Lamar, 2004: maps 79, 80) with a vertical distribution from c. 1400–3491 m.

Common name: Middle American montane pitvipers.

Definition and diagnosis: Rostral wider than high, front surface flat; three preoculars, upper largest, entire, and squarish, lower forming posterior border of pit and excluded from orbit; single, large, flat, plate-like supraocular above eye; seven to 11 supralabials; eight to 12 infralabials; canthals and internasals relatively large and flat; two to seven intersupraoculars; crown of head covered with variably sized, flat or keeled scales; keeling prominent in parietal area; second supralabial discrete from prelacunal; supralabial and subocular series in contact or separated by single row of scales; 19–23 (mode 21) middorsal dorsal scale rows; mid-dorsal scales at midbody moderately slender and pointed; 120–150 ventrals; 22–36 undivided subcaudals; tail spine straight, moderately long.

Lateral edge of nasal broadly expanded, bone roughly quadrangular; frontal bones mostly flat, dorsal surface with slightly elevated margins, longer than wide; postfrontal large, not reaching frontal; transverse distance of postfrontal greater than its distance along parietal bone; posterolateral edges of dorsal surface of parietals forming low to moderately distinct raised ridge continuing posteriorly on parietal as low ridge; junction between parietal and prootic rounded to almost flat; squamosal extending to level posterior to posterior edge of exoccipital; ectopterygoid about same length as expanded, flattened base of pterygoid (posterior to the articulation with ectopterygoid) with flat shaft gradually tapering posteriorly; dorsal surface of parietal roughly triangular to sometimes rounded; three to five palatine teeth; seven to 18 pterygoid teeth; eight to 16 dentary teeth; pterygoid teeth extending just posterior to level of articulation of pterygoid with ectopterygoid in C. godmani , but not reaching this far back in congeners; maxillary fang relatively short, being about equal in length to height of maxilla; fang at rest extending to level of about middle of supralabial 5 or suture between supralabials 5–6 (mostly after Campbell & Lamar, 2004).