New York, N.Y. : American Museum of Natural History
Abstract
37 p. : ill., map ; 24 cm.Includes bibliographical references (p. 35-37)."Saphenophis, new genus, accommodates five species of South American colubrid snakes: Dromicus boursieri Jan and Sordelli (type species), Liophis atahuallpae Steindachner, Rhadinaea antioquiensis Dunn, Rhadinaea tristriatus Rendahl and Vestergren, and Saphenophis sneiderni, new species (from southwestern Colombia). These are defined and diagnosed, and placed in two species groups. No support is given a recent suggestion that the type species (boursieri) may be closely allied with some West Indian snakes (Antillophis Maglio, 1970). Saphenophis belongs with an undefined group of New World colubrid genera characterized by a usually bilobed, spinose hemipenis that is distally calyculate and noncapitate or semicapitate (but lobes not contained within single capitulum), with a deeply forked sulcus spermaticus. It is suggested that this type of hemipenis is more primitive than the single or slightly bilobated type in which the entire calyculate area is contained within a single capitulum and bifurcation of the sulcus spermaticus is reduced. Saphenophis boursieri occurs on both Pacific and Atlantic drainages; it possibly adapted to a wide range of environments in the course of vertical habitat displacement during Pleistocene glaciation. Other species of Saphenophis are thought to be isolates differentiated from stock(s) fragmented by upward displacement of montane habitats, in a drier postglacial period. Thus, evolution of some or all the species is suggested to have occurred fairly recently in the Quaternary"--P. [1]