Dipsas latifrontalis (Boulenger, 1905)

Arteaga, Alejandro, Salazar-Valenzuela, David, Mebert, Konrad, Penafiel, Nicolas, Aguiar, Gabriela, Sa ́ nchez-Nivicela, Juan C., Pyron, R. Alexander, Colston, Timothy J., Cisneros-Heredia, Diego F., Yanez-Munoz, Mario H., Venegas, Pablo J., Guayasamin, Juan M. & Torres-Carvajal, Omar, 2018, Systematics of South American snail-eating snakes (Serpentes, Dipsadini), with the description of five new species from Ecuador and Peru, ZooKeys 766, pp. 79-147 : 101-102

Dipsas latifrontalis (Boulenger, 1905)

Leptognathus latifrontalis Boulenger, 1905: 561. Holotype BMNH 1946.1.20.98, a female from Aricagua, state of Mérida, Venezuela.

Dipsas peruana Harvey & Embert, 2008: 79 (part).

Proposed standard English name.

Broad-fronted Snail-Eater

Proposed standard Spanish name.

Caracolera frentona

Diagnosis.

Dipsas latifrontalis differs from all described species of Dipsas based on the following combination of characters: (1) 15/15/15 smooth dorsals with moderately enlarged vertebral row; (2) one loreal and one preocular in contact with orbit; (3) 8-10 supralabials with 3rd to 6th contacting orbit; (4) one pair of infralabials in contact behind symphysial; (5) 192 ventrals in one male (CVULA 7883), 194 in the female holotype; (6) 109 divided subcaudals in the single male, 95 in the female holotype; (7) dorsal and ventral ground color bronze (light brown in juveniles) with 32-36 dark reddish brown to black, circular to vertically elliptical blotches that are longer than interspaces and white to cream edged on first half of body; head grayish brown to black with different degrees of whitish edging on the labial scales, and with or without a thin (1-2 scales long) dingy white irregular nuchal collar; dorsal blotches extending marginally onto ventrals and occasionally fusing on the anterior part of the body; (8) 800 mm SVL in the holotype female; (9) 220 mm TL in the holotype female.

Comparisons.

Dipsas latifrontalis is compared to species previously subsumed under D. peruana : D. palmeri , D. peruana , and the herein described D. klebbai . From D. palmeri , it differs in having the first 9-10 dorsal blotches edged with white or cream, vs. the first 19-35 in D. palmeri . The only known adult of D. latifrontalis photographed in life has bronze interspaces (Fig. 1n), a coloration not seen in any adult of D. palmeri (see also Remarks below). From D. klebbai , it differs in having shorter blotches (longest blotch up to 6-8 vertebral scales long) that are circular (instead of oblong) and that are only longer than the interspaces on the first half of the body. From D. peruana , it differs in having dorsal blotches in posterior half of the body shorter than interspaces, and in lacking melanized interspaces in adult individuals.

Distribution.

Known only from two localities in the Venezuelan Andes and one in the Northern Colombian Andes at elevations between 1000 and 1400 m (Fig. 4).

Remarks.

Neither Peters (1960) nor Harvey and Embert (2008) examined the holotype of Dipsas latifrontalis , and they used Boulenger (1905) description to assign specimens of D. palmeri and D. peruana , respectively, to D. latifrontalis . We examined pictures of the holotype of D. latifrontalis from the BMNH, provided to us by César L. Barrio-Amorós. In coloration, the holotype is nearly identical to the uncollected adult presented in Figure 1n (San Isidro, Barinas province, Venezuela), with faint cream edging restricted to blotches 1-9, and indistinct blotches on the posterior part of the body. The previously only known photograph of a D. latifrontalis is of a juvenile from the same location as the specimen in Figure 1n ( Rivas et al. 2012).

All Dipsas latifrontalis depicted in Lotzkat et al. (2008) and Natera-Mumaw et al. (2015) refer to a different species related to the D. incerta group, except for the holotype of D. latifrontalis BMNH 1946.1.20.98 (formerly 1905.5.31.76).