Comprehensive DescriptionRead full entry
Diagnosis: Medium-sized body, 39.6 mm to 46.4 mm SVL. Tail is slender and longer than the body (46.5-63.9 mm tail length, tail:body ratio of 1.35), with a slight constriction at the base. Snout is truncate with the upper jaw protruding beyond the lower. Large nostrils, located near the angles of the snout. Limbs are quite long, with toes overlapping a distance of 2 costal folds when appressed. Toes are spatulate and are webbed, with Toe I both reduced and enclosed in webbing; in contrast, each outer digit has one phalanx free from the webbing. This species has 12 or 13 costal grooves. Vomerine teeth are present in 2 arched series with 8 to 13 teeth in each series. Males have posterior maxillary teeth, like C. multidentata but unlike C. chiropterus. This species can be distinguished from C. multidentata by having 12 costal grooves, Finger II longer than Finger IV, longer legs, a shorter head, and more vomerine teeth. It can be distinguished from C. chiropterus by having limbs that overlap when adpressed, proportionately longer front legs, more extensive foot webbing, a proportionately longer, more slender, and less basally constricted tail, longer and more widely separated vomerine tooth series, and (as previously mentioned) by C. mosaueri males having posterior maxillary teeth (Woodall 1941).
Description: Head has a truncated oval shape when viewed from above. Snout is truncate, with the upper jaw projecting beyond the lower jaw. Nares are large. Snout swollen below nostrils. Vomerine teeth are present in two curved series (13-10), with the distance separating the series equal to 2/3 the choanal diameter. Parasphenoid teeth are present in two distinct series, separated from vomerine teeth by 2x the choanal diameter, and with the series widening and diverging slightly at the posterior. Premaxillary-maxillary teeth number 31-25, and males have posterior maxillary teeth. Mandibular teeth number 34-38. Gular fold is well-defined, extending up the sides of the neck to join a median longitudinal groove. Males have a mental gland underneath the chin. Larger specimens have 12 costal grooves and smaller ones have 13 costal grooves. The costal grooves approach the dorsal midline but do not meet there, whereas they are continuous across the belly. Limbs are long; the overlap for adpressed toes is equivalent to two costal folds. Fingers are flattened. Relative finger length is 3>2>4>1, with finger I strongly reduced and fully embedded in the webbing. The tail is rounded in cross-section, has a slight constriction at the base, and is longer than the body, with the ratio of tail length to body length being 1.35. Vent is surrounded with papillae.
Preserved specimens are uniformly dark brown on the dorsum and nearly uniform light tan on the venter, with only a few pigment granules visible ventrally on the chest and under the limbs and tail (Woodall 1941).
This species was first described by Woodall (1941), as Oedipus mosaueri. Woodall (1941) thought this species was closely related to Chiropterotriton multidentatus (then known as Oedipus multidentata) and Darda (2004) thought that it might be conspecific with C. multidentatus.
The specific epithet was given in honor of Dr. Walter Mosauer, a herpetologist and professor at UCLA, who specialized in the study of Mexican amphibians and reptiles. C. mosaueri was collected during his final field expedition (Woodall 1941).