Synophis zaheri, Pyron, R. Alexander, Guayasamin, Juan M., Penafiel, Nicolas, Bustamante, Lucas & Arteaga, Alejandro, 2015

Pyron, R. Alexander, Guayasamin, Juan M., Penafiel, Nicolas, Bustamante, Lucas & Arteaga, Alejandro, 2015, Systematics of Nothopsini (Serpentes, Dipsadidae), with a new species of Synophis from the Pacific Andean slopes of southwestern Ecuador, ZooKeys 541, pp. 109-147 : 114-115

Taxon classification Animalia Squamata Colubridae

Synophis zaheri sp. n. Figs 3, 5, 8

Holotype.

MZUTI 3353 (Fig. 3A), an adult male collected on 30 December 2013 at ~2200h by Alejandro Arteaga, Lucas Bustamante, Rita Hidalgo, Daniel Mideros, and Diana Troya, in the vicinity of Buenaventura Reserve ( Fundación Jocotoco), near Piñas, El Oro Province, SW Ecuador, 874m above sea level (-3.65, -79.76; Fig. 5), in a narrow band of cloud forest on the Pacific versant of the Andes.

Paratype.

MZUTI 3355 (Fig. 3B), adult male collected a few minutes after the holotype, a few meters away.

Etymology.

Named after the preeminent Brazilian herpetologist Hussam El-Dine Zaher, for his innumerable contributions to South American herpetology and snake systematics.

Diagnosis.

Synophis zaheri can be differentiated from Diaphorolepis by an unmodified vertebral scale row with a single weak keel (versus a laterally expanded vertebral scale row, bicarinate or smooth); from Emmochliophis by the presence of a loreal (versus absence); from Synophis bicolor by having 166-169 ventrals (versus 174-183) and 111-112 subcaudals (versus 129-143); from Synophis aff. bicolor by having 8 or 9 infralabials (versus 10 or 11) and lighter brown dorsal coloration in life (versus darker black); from Synophis cf. bicolor by having 166-169 ventrals (versus 184-193), 111-112 subcaudals (versus 127-131), and 8 or 9 infralabials (versus 10-12); from Synophis calamitus by having two postoculars (versus one typically) and internasals in contact (versus divided typically); from Synophis lasallei by having 166-169 ventrals (versus 144-165), 19 dorsal scale rows at midbody (versus 21-23 typically), 8 or 9 infralabials (versus 10 or 11), and by having the anteriormost dorsal scale rows smooth (versus keeled); and from Synophis plectrovertebralis by absence of a nuchal collar (versus presence) and two postoculars (versus one).

Description.

Small-sized snakes (351-372mm SVL, 184-194mm TL) with slender bodies and head distinct from neck. Eye large (>1/3 head height), bulbous, and black in life, with pupil not easily distinguishable from iris. Pupil round in preservative (though this may be an effect of fixation). Dorsum coloration grayish-brown with iridescent sheen in life and preservation, no light-colored nuchal collar in adults, and posterior supralabials mostly pigmented (>50%). Ventral coloration primarily bright yellowish-white, extending onto margins of ventral scales and supralabials. Posterior one-third of ventral surface anterior to vent becomes increasingly mottled, and ventral surface of tail color of dorsum. Squamation pattern includes 166-169 ventral scales, 111-112 subcaudals, 19-19-17 dorsal scale rows (scale-row reduction of 2 rows past midbody), anal single, no apical pits, mid-body dorsal scales with weak single keel (first few dorsal scale-rows smooth), vertebral scale row not enlarged, nuchal scales smooth, 8 supralabials, 8 or 9 infralabials, 2 postoculars, loreal present, nasal undivided, fused prefrontals, internasals in contact, and rostral concave. Condition of the vertebrae, which are heavily modified in Emmochliophis and Synophis ( Fritts and Smith 1969; Savitzky 1974; Hillis 1990) unknown, pending skeletal preparation or micro- CT scanning. Everted hemipenes are slightly bilobed, semicalyculate, and semicapitate, relatively stout and bulbous, covered in large spines or hooks, similar to that of Diaphorolepis and Synophis aff. bicolor and Synophis lasallei ( Bogert 1964; Zaher 1999; Martinez 2011). Both specimens were active by night in primary evergreen foothill forest, with canopy cover between 70 and 100%. The holotype MZUTI 3353 was found on the ground, whereas the paratype MZUTI 3355 was found 50 cm above the ground in a bush. Neither were found close to water, but were active after a rainy day.

In light of this new species and the updated material we have located and examined (Tables 1, 2), we have prepared updated accounts for the tribe and the other species. Hopefully, these will serve as useful descriptive summaries for taxonomic boundaries, species delimitation, and the assignment of new specimens and populations to species-level groups. We focus primarily on the external morphological characters that will be of greatest use for identifying specimens in the field and from preserved collections. In some cases, more detailed information can be found in the original descriptions cited. The tribe name Diaphorolepidini was introduced in the PhD thesis of Jenner (1981), for which availability as a published work is ambiguous. We conservatively continue to credit the name to her, rather than treat it as unavailable and re-describe it ourselves.