A Review of the Frogs of the Hyla bistincta Group

A Review of the Frogs of the Hyla bistincta Group

In the mountainous regions of Middle America there are several groups of hylid frogs that inhabit mountain streams. Some of these groups, such as Plectrohyla and Ptychohyla, have been elevated to generic rank, whereas others are retained in the large and complex genus Hyla. In the mountains of Mxico five species of hylids that seem to compose a phyletic unit are herein referred to as the Hyla bistincta group. Since 1955 I have been accumulating specimens of, and data on, this group with the result that all specimens known to me, including the types of all named taxa, have been studied. Detailed observations have been made on the ecology and life histories of three of the species; the other two species are known to me only from preserved specimens. The five species comprising the Hyla bistincta group are moderate-sized hylids having rather blunt heads and robust bodies. The fingers are long and have little webbing (Fig. 1). The skin of the dorsum is thick and glandular, but not tuberculate. An anal sheath is present. The skull is rather broad, flat, and solidly roofed. The ethmoid is broad, curved downward laterally, and solidly sutured to the frontoparietal. The nasals are broad, sutured for their entire width with the ethmoid, and broadly in contact medially. The premaxillaries are in contact medially; each has a long, flat nasal process. The quadratojugal is absent, and the maxillary tapers to a point posteriorly. There is no squamosal-maxillary connection. The maxillary and premaxillary teeth are rather long, bifid, and moderately spatulate. Some teeth on the premaxillary and anterior part of the maxillary are hooked. The vomerine teeth are spatulate and bifid. A broad, flat, ossified prepollex is present but does not project as a spine. The known tadpoles have ventral mouths, tooth-rows, two or more rows of labial papillae, and long tails with low fins. [Pg 473] As thus defined the Hyla bistincta group can be distinguished from all other groups of Middle American frogs by the combination of absence of the quadratojugal, non-projecting prepollex, long fingers with little webbing, and stream-inhabiting tadpoles having tooth rows and two or more rows of labial papillae. ......Buy Now (To Read More)

Product details

Ebook Number: 32653
Author: Duellman, William Edward
Release Date: Jun 2, 2010
Format: eBook
Language: English