Dipsas klebbai, 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

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 : 95-98

Dipsas klebbai sp. n. Figs 1l, m, 15, 16

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

Proposed standard English name.

Klebba’s Snail-Eater

Proposed standard Spanish name.

Caracolera de Klebba

Holotype.

MZUTI 5412 (Figs 15, 16), adult male collected by Phillip Torres on April 28, 2016 at Pacto Sumaco, province of Napo, Ecuador (S0.66377, W77.59895; 1556 m).

Paratypes.

DHMECN 568, adult female collected by Thomas Begher on 1980 at Borja, province of Napo, Ecuador (S0.42054, W77.84104; 1717 m). MCZ 164674-75, two adults of undetermined sex collected by Giovani Onore on June 01, 1983 at Río Azuela, province of Napo, Ecuador (S0.148693, W77.65463; 1402 m). MHNG 2220.035, 2220.056, 2250.063, 2250.064, one juvenile female and three adult males, respectively, collected by Giovani Onore on 1984 at El Chaco, province of Napo, Ecuador (S0.33763, W77.80957; 1595 m). MHNG 2220.038-039, adult female and adult male, respectively, collected by Giovani Onore on November 1984 at San Rafael, province of Napo, Ecuador (S0.09669, W77.58995; 1464 m). MHNG 2220.04, 2220.041, adult females collected by Giovani Onore on May 1984 at El Reventador, province of Napo, Ecuador (S0.04480, W77.52858; 1476 m). MZUTI 63, adult male collected by Alejandro Arteaga on August 08, 2011 at Yanayacu, province of Napo, Ecuador (S0.60042, W77.89053; 2110 m). MNHG 2529.029, adult female collected by Eugen Kramer on February 22, 1992 at Napo province, Ecuador. QCAZ 12488, collected by Pablo Medrano on March 02, 2015 at Río Quijos, province of Napo, Ecuador (S0.45224, W77.94249; 1929 m). QCAZ 12600, collected by Pablo Medrano on March 27, 2014 at Santa Rosa, province of Napo, Ecuador (S0.39630, W77.82343; 1113 m). QCAZ 13124, collected by Fabián Vallejo on November 21, 2014 at Las Palmas, province of Napo, Ecuador (S0.54691, W77.87762; 1903 m). QCAZ 14281, adult male collected by Andrea Narváez on December 02, 2016 at La Bonita, province of Sucumbíos, Ecuador (N0.47209, W77.54661; 1953 m). QCAZ 1496, collected on October 18, 1992 at Sardinas, province of Napo, Ecuador (S0.38484, W77.83782; 1641 m). QCAZ 1605, adult male collected by Victor Utreras on February 04, 1992 at 2 km E Borja, province of Napo, Ecuador (S0.41543, W77.83032; 1608 m). QCAZ 250, adult male collected at El Reventador, province of Napo, Ecuador (S0.04480, W77.52858; 1476 m). QCAZ 358-59, collected on January 10, 1984 at Cascada de San Rafael, province of Napo, Ecuador (S0.10354, W77.58337; 1246 m). QCAZ 4500, collected by Estefanía Boada on August 01, 2011 at Hostería Cumandá, province of Napo, Ecuador (S0.45249, W77.88071; 1856 m). QCAZ 9696, collected by Steven Poe on August 04, 2009 at 2.3 km N of turnoff to Baeza, province of Napo, Ecuador (N0.45236, W77.88212; 1840 m). USNM 386323, adult female col lected on February 24, 1979 at Río Azuela, province of Napo, Ecuador (S0.148693, W77.65463; 1402 m). ZSFQ D304, female collected by Jean-Marc Touzet and Diego F. Cisneros-Heredia at Cascada de San Rafael, province of Napo, Ecuador (S0.10007, W77.58034; 1182 m).

Diagnosis.

Dipsas klebbai is placed in the genus Dipsas based on phylogenetic evidence (Fig. 3), and the absence of a labial that is noticeably higher than other labials and in contact with the postocular, primary and secondary temporals. The species differs from all described species of Dipsas based on the following combination of characters: (1) 15/15/15 smooth dorsals with enlarged vertebral row (1.5-1.8 times as wide as adjacent rows); (2) one loreal and one preocular in contact with orbit; (3) 9-11 supralabials with (usually) 4th to 6th contacting orbit; (4) one pair of infralabials in contact behind symphysial; (5) 181-201 ventrals in males, 187-194 in females; (6) 99-123 divided subcaudals in males, 98-106 in females; (7) dorsal and ventral ground color light brown with various degrees of fine black speckling and 27-36 dark brown to black, cream-edged oblong blotches that are longer that interspaces and become smaller towards the tail (Fig. 2m, n); on first half of body, the dark bands meet ventrally to form full body rings; on second half they fail to meet ventrally; head black with different degrees of whitish edging on the labial scales, and a thin (1-2 scales long) cream to light brown irregular nuchal collar; dorsal blotches usually incomplete ventrally, extending far onto ventrals and occasionally fusing midventrally; cream edges of neighboring blotches fused in first 6-9 blotches; (8) 401-749 mm SVL in males, 525-630 mm in females; (9) 169-330 mm TL in males, 209-240 mm in females.

Comparisons.

Dipsas klebbai is compared to species previously subsumed under D. peruana : D. latifrontalis , D. palmeri , and D. peruana . From D. latifrontalis (Fig. 1n) and D. palmeri (Figs 1r, s), it differs in having longer oblong to rectangular body blotches up to 7-13 vertebral scales long (vs. fewer than 8 vertebral scales long in D. latifrontalis and D. palmeri ) that are also longer than the interspaces (Fig. 1l, m). Specimens of D. klebbai can be separated from specimens of D. peruana , with the exception of BMNH 1946.1.2078, based on the presence of the following characteristics (condition of D. peruana in parentheses): posterior body blotches twice to four times as long as interspaces (vs. posterior body blotches ca. equal in length or marginally longer than interspaces); interspaces never completely obscured by black pigment (vs. completely melanized in some specimens); dorsal surface of head black (vs. dark brown with dingy cream reticulations); dorsal body blotches fused ventrally on the first half of the body (vs. rarely fused); longest body blotch at least 7 vertebral scales long (vs. longest body blotch 4-7 vertebral scales long). Genetic divergence in a 684 bp long fragment of the mitochondrial Cytb gene between D. klebbai and D. palmeri is 8.2-9.2%, whereas intraspecific distances are less than 1.1% in both species. For the same fragment, the distance between D. klebbai and D. peruana is 10.7-11.0%.

Description of holotype.

Adult male, SVL 608 mm, tail length 262 mm (43% SVL); head length 20.3 mm (3% SVL) from tip of snout to commissure of mouth; head width 12.7 mm (62% head length) taken at broadest point; snout-orbit distance 5.4 mm; head distinct from neck; snout short, blunt in dorsal and lateral outline; rostral 4.0 mm wide, broader than high; internasals 2.6 mm wide, as broad as long; prefrontals 3.9 mm wide, broader than long, excluded from entering orbit by preocular; supraocular 4.3 mm long, broader than long; frontal 4.5 mm long, hexagonal, in contact with prefrontals, supraoculars, and parietals; parietals 6.6 mm long, longer than broad; nasal divided, in contact with first two supralabials, loreal, prefrontal, internasal, and rostral; loreal 2.6 mm long, slightly longer than high, entering orbit; eye diameter 4.5 mm; pupil semi-elliptical; one preocular; two postoculars; temporals 2+2; ten supralabials, 5th and 6th contacting orbit; symphysial separated from chinshields by the first pair of infralabials; 14 infralabials, 2-7 contacting chinshields; anterior pair of chinshields longer than broad, posterior pair broader than long; dorsal scales in 15/15/15 rows, smooth, without apical pits; 188 ventrals; 116 divided subcaudals; cloacal plate single.

Natural history.

At night (21h53-02h13), specimens of Dipsas klebbai have been found active during or after light rain on arboreal vegetation 50-500 cm above the ground in a variety of environments ranging from primary montane cloud forests and evergreen montane forests to silvopastures and forest borders, occasionally close to rivers. By day, individuals have been found hidden underground in pastures or among shrubs in rural gardens, or coiled on leaves at 300 cm above the ground. At dusk, after warm days, individuals of Dipsas klebbai have been seen crossing roads. QCAZ 13124 laid six eggs on December 2014. Five eggs were found inside a rotten trunk at El Chaco, province of Napo Ecuador.

Distribution.

Endemic to the eastern slopes of the Ecuadorian Andes in the provinces of Napo and Sucumbíos at elevations between 1246 and 2120 m (Fig. 4).

Etymology.

Named after Casey Klebba, in recognition of his appreciation of and passion for Andean wildlife, and his invaluable support of AA’s field expeditions to remote areas of Ecuador. After a visit to Peru in 2011, Casey became an active supporter of conservation and scientific projects in Ecuador.

Conservation status.

All known localities of occurrence for Dipsas klebbai fall within the limits or within the buffer zone of the following protected areas: Parque Nacional Cayambe Coca, Parque Nacional Sumaco Napo Galeras, Reserva Ecológica Antisana, and Reserva Ecológica Cofán Bermejo. Furthermore, the species is common in degraded environments, which suggests a degree of tolerance for habitat modification. For these reasons, and because it does not meet the criteria (IUCN 2001) for qualifying in a threatened category, we here list it as Least Concern following IUCN guidelines.

Remarks.

In their revision of Dipsas peruana , Harvey and Embert (2008) included specimens of D. klebbai . However, they found no characters that could diagnose these specimens from the rest of Ecuadorian and Peruvian specimens of D. " peruana " in order to establish species boundaries. They also grouped the then valid D. boettgeri , D. latifrontalis , and D. polylepis under D. peruana . The authors were right to point out that the different populations cannot be separated based on characters of lepidosis. However, they did not include molecular data in their analyses, and also failed to notice the geographically structured differences in the length of the body blotches and their relationship to the length of the interspaces.