Leptophis haileyi (Family Colubridae)

 Size: 857 mm SVL, TL 1.4 m.  The only Trinidad and Tobago Leptophis species to have a subacuminate snout in profile, the rostral barely visible from above, and the primary temporal in contact with three or four upper labials. Tobago specimens of L. coeruleodorsus have two upper labials contacting the primary temporal with the last upper labial excluded from primary temporal contact. In L. haileyi, the last upper labial makes narrow contact with the primary temporal.  Leptophis haileyi has longitudinal dorsolateral stripes on the anterior body scale rows 2–4; nine upper labials, 2–3–4 at the loreal-prefrontal shield, 5–6 in the orbit; 5/4 lower labials at the first pair of chin shields. Similar species: L. coeruleodorsus on Tobago has eight upper labials with 2–3 contacting the loreal-prefrontal shield, 4+5 in the orbit, and two upper labials contacting the primary temporal. This species can also be distinguished from L. coeruleodorsus by its domed snout (prefrontal –internasal area), its relatively high ventral count (173), and proportionally shorter tail. The male holotype has a tail:SVL ratio (0.64) and a subcaudal count (166) that fall within the range of L. coeruleodorsus females. Distribution: Roxborough River drainage of Tobago.  

Erythrolamprus cobellus (Family Dipsadidae)

Other common names: Mapepiri mangue, mangrove snake, mangrove mapepire. Size: 572 mm SVL, tail 222 mm.  A mostly black, semi-aquatic snake with a black-brown dorsum with white flecks, the belly has transverse bands. Dorsal scales smooth in 17 rows at mid-body reduced to 15 near the vent. Rostral visible from above; nasal divided; one preocular, loreal small and single; two postoculars; seven to nine upper labials; 8−11 lower labials; ventrals 130−147; cloacal plate divided; 37−56 paired subcaudals. All other Trinidad and Tobago Erythrolamprus have longitudinal stripes; transverse bands, or dorsal blotches. Because the dorsum may be almost entirely black, it could be confused with Clelia (19 scale rows and more than 200 ventrals) or Spilotes (16 or 18 scale rows, mostly keeled, and more than 200 ventrals). Widespread in northern South America - Colombia, Venezuela, Trinidad, the Guianas, Brazil, and Ecuador. Semi-aquatic in fresh and brackish water; present in mangroves swamps, herbaceous swamps, rice paddies, associated streams. Regularly travels overland and may be seen on roads. Active late afternoon and after dark. Diet: includes a variety of small vertebrates. Reported to lay eggs in June, clutch sizes less than six eggs. 

Shaw's Black-backed Snake, Erythrolamprus melanotus nesos (Family Dipsadidae)

Other common names: Beh belle chemin (=beauty of the road), squirrel snake; on Tobago: doctor snake.
Size: 604 mm SVL, 150 mm tail. Rostral visible from above; nasal divided; one preocular, loreal small and single; two postoculars; seven to eight upper labials; seven to nine lower labials; ventrals 142−156; cloacal plate divided; 54−63 paired subcaudals. Dorsal scales smooth, contain one apical pit, and are in 17 rows that reduce to 15 posteriorly.  Similar Species: the only snake in Trinidad and Tobago with a broad black dorsal stripe five scales wide bordered with yellow or salmon on the sides; head usually olive-brown or black. Endemic to Trinidad and Tobago. A forest snake that is closely associated with streams and ponds, uses cacao plantations and other disturbed habitats. Diurnal. Diet includes small vertebrates, mostly frogs (Engystomops pustulosus, Pristimantis urichi) tadpoles, and lizards (Bachia trinitatis, Gonatodes vittatus). Clutches of 2−10 eggs have been reported between January and August.

Neotropical Racer, Mastigodryas boddaerti (Family Colubridae)

Juvenile

Size: 877 mm SVL, 1187 mm TL, can reach 1.4 m; hatchlings 250 mm. Dorsal scale rows 17 at mid-body, reduced to 15 posteriorly; each scale has a pair of apical pits, otherwise smooth. Rostral visible from above; nasals divide, nostril large; loreal rectangular; one preocular; two or three postoculars;  upper labials 8−10, lower labials 8−10; ventrals 179−196; divided cloacal plate; 106−124 divided subcaudals; eyes large. A lateral stripe on scale rows 4–5. Juveniles are red brown with about 72 white dorsal cross bands, each bordered with black. The colors change to olive green or olive brown with maturity. The combination of 17 rows of dorsal scales with apical pits, a loreal, a vertebral scale row that is not enlarged, and five lower labials in contact with the first chin shield, will separate the species from all other Trinidad and Tobago snakes, except for the two other species of Mastigodryas. The Tobago Racer, M. dunni, is restricted to that island and has an extra stripe on scale rows 1−2. The Yellow-necked Racer may be found (not confirmed) on both Trinidad and Tobago and potentially sharing habitat with this species and M. dunni and it has a stripe on the anterior body that spans scale rows 3−4−5.  A common, fast moving, ground dwelling, forest snake often in leaf litter but it will enter grassy areas at forest-edge and ponds. Diurnal. Diet includes insects, frogs, lizards, nestling birds, rodents, and reptile eggs. A study on a Brazilian population found lizards made up 74% of the diet, followed by mammals and frogs; it also reported female’s take a wider range of prey than males, and female feed when carrying eggs. Females deposit eggs in May. Other common names: Boddaert's tropical racer, grass machete, couesse grass snake.

Erythrolamprus zweifeli (Family Dipsadidae)

Size: 509 mm TL, maximum total length may approach 800 mm.  Rostral visible from above; divided nasal; single loreal; single preocular; two (occasionally one) postocular; seven to nine upper labials; 8–10 lower labials; 137–146 ventrals; divided anal plate; 61–80 paired subcaudals; dorsal scales are smooth, in 17 rows at midbody reduce to 15 posteriorly. Dorsum can be olive green with each scale edged with black or a uniform brown above; crown with a black blotch; black stripe posterior to the eye; tail with black stripe on each side, venter red-pink or cream with black checkering on some scutes. The two color morphs of this snake make it somewhat confusing: the “salt & pepper morph” is readily distinguished from all T&T snakes at a glance, and the brown –green morph may be confused with Leptodeira (19 dorsal scale rows) or Mastigodryas (170 or more ventrals), but this species has a red and black belly not found in either of these species. Trinidad Erythrolamprus well as other colubrid snakes. A forest and forest-edge snake; often in the vicinity of streams. Diurnal. Diet includes frogs (hylid frogs, Leptodactylus sp., Mannophryne trinitatis, Scinax rubra), lizards (Ameiva atrigularis), and small birds. When disturbed neck is flattened to form a small, narrow hood.

Tobago Racer, Mastigodryas dunni (Family Colubridae)

Size: 776 mm SVL, 881 mm TL, hatchlings 240 mm. Identification: Dorsal scale rows 17 at mid-body, reduced to 15 posteriorly; each scale has a pair of apical pits, otherwise smooth. Rostral visible from above; nasals divide, nostril large; loreal rectangular; one preocular; two or three postoculars;  upper labials 8-10, lower labials 8-10; ventrals 185−196; divided cloacal plate; 119−124 divided subcaudals; eyes exceptionally large. The dorsum is blue-gray, a light, indistinct  stripe present on scale rows 1-2, a more distinct stripe present on rows 4-5, laterally coloration becomes lighter, including light labials; the venter is white-pink with some blotches; the underside of the tail may be flecked with gray. It is likely that the juveniles are blotched with cross bands like M. boddaerti and that the colors change to an blue-gray with maturity. The combination of dorsal scales in 17 rows at mid body, scales with apical pits, a loreal, a vertebral scale row that is not enlarged, and five lower labials in contact with the first chin shield, and two lateral stripes one scale row 1–2 and a second on rows 4–5 should separate the species from all other Trinidad and Tobago snakes, except the other two species of Mastigodryas . The Tropical Racer, M. boddaerti is restricted to Trinidad, but the Yellow-necked Racer, M. amarali, is not confirmed from  the islands. The two may be distinguished by a stripe on the anterior body that spans scale rows 3−4−5 in the Yellow-necked Racer, and only rows 4-5 in this species. Known only from Tobago and Little Tobago Islands. A forest and forest-edge species. Diurnal. Diet probably similar to the Tropical Racer, but it has not been studied.

Ratonel, Pseudoboa neuwiedii (Family Dipsadidae)

Other common names: roulea, mapepire velour, ratonera, moon snake, brown snake.

Size: 870 mm SVL, 215 mm tail; 1085 mm TL. Rostral slightly upturned, visible from above; loreal single; one or two preoculars; two postoculars; eight upper labials; 6–8 lower labials; 195–201 ventrals; single cloacal plate; and 74–97 single subcaudals; dorsal scales smooth in 17 or 19 rows at midbody. Adult snakes are red-brown or pink-brown with a darker brown-black head; Young red or pink above with a dark head and a cream collar that fades with age. Each dorsal scale with a dark spot enlarging with age; venter uniform cream. Adults are a uniform salmon color with a dark head. Juveniles have been confused with its close relative Clelia clelia; both species have hatchlings and juveniles that are pink-red to bright red with a black head, light colored band, followed by a black band.  However, the uniquely shaped upturned rostral and single subcaudals, will separate Pseudoboa from Clelia. Oxyrhopus petolarius, may be banded or a uniform black, but it lacks the up-turned rostral and has divided subcaudals. A widespread species, from Panama and Colombia eastward to Suriname, and south to Brazil; widely distributed on both Trinidad and Tobago.  Forest, savanna; common in most habitats, including: agricultural areas, gardens, yards, and plantations. Crepuscular, nocturnal. Diet includes: any appropriately sized vertebrate killed with a combination of constriction and venom; Ameiva atrigularis seems to be a frequently taken prey species; and they have been suggested to be nest predators. May actively forage on the ground or hunt from ambush in low vegetation.  Clutches of 3–9 eggs laid in leaf cutting ant nests in July, September, January, and February. Venom: Anecdotal evidence suggests this snake’s venom may be quite toxic to both mammals and reptiles; it usually does not attempt to bite when picked-up but it should be handled with care.

Cutlah, Phrynoax polylepis (Family Colubridae)

Size: 870 mm SVL, 1235 mm TL, may exceed 2135 mm TL, hatchlings 255 mm. Identification:  Adults a uniform olive green with some, but not all scales keeled in 21 or 23 rows at mid-body reduced to 15 rows posteriorly, and upper labials 4-5-6 in the orbit. Young (<495 mm TL) have crescent-shaped blotches that form cross bands on the dorsum.  Rostral visible from above; nasals single; loreal single; one preocular; two postoculars;  seven upper labials,10−11 lower labials; ventrals 193−203; cloacal single; divided subcaudals 156−181 in males 125−126  in females; dorsal scales smooth with apical pits. Perhaps most easily confused with snakes of the genus Chironius which have 10 or 12 dorsal scales at mid-body; and with Spilotes sulphureus which has a black and yellow dorsum and upper labials 4−5 on the orbit. Ranges from Columbia to the Guianas, including Trinidad, and southward into the Amazon basin. An arboreal snake of forest and forest-edge habitats. Diurnal and crepuscular. Diet: Actively forages for nestling birds and eggs; probably a specialized nest predator; but will also prey on lizards and mammals. Defense: Cryptic behavior includes kinking its body into a shape that resembles a liana to avoid detection; behavior includes inflate its forebody, gape its mouth, actively striking, and vibrating its tail when disturbed. 

Slug-eating Snake, Sibon nebulata (Family Dipsadidae)

Other common names: Mapepire corde violin, fiddle string mapepire; cloud snake, cloudy snake.

Size: 440 mm SVL; 158 mm tail; total length about 1 meter. Identification: A medium sized, gray to brown blotched snake with a mottled pattern; body slightly compressed, slender forebody, wide head, large eyes. Smooth dorsal scales in 15 rows, not reduced posteriorly; the vertebral row is slightly enlarged (scales about 1.5 times wider than lateral scales). Rostral barely visible from above, nasals divided, loreal contacts the orbit; preocular usually absent; postoculars two; upper labials 7−8, 4−5 or 5−6 in orbit, 2−3−4 usually contact the loreal; lower labials 8-10; ventrals 169−182 in Trinidad and Tobago specimens, not sexual dimorphic, subcaudals in males 89−113, in females 84−90. Three pairs of chin shields, the first pair in contact with five or six lower labials.  The only Trinidad and Tobago snake with 15 rows of smooth scales rows at midbody, a slightly enlarged row of vertebral scales, and a mental groove. The dorsum is usually gray with 36−41 brown to black blotches. Most easily confused with Dipsas trinitatis which lacks the mental groove; and with Imantodes cenchoa, an extremely slender snake with 17 scale rows at mid-body. This is a widespread species, ranging from Veracruz and Nayarit, Mexico, to Brazil and Ecuador. S. n. nebulata occurs in the northern portion of this range, including Trinidad, Tobago and the Bocas. Habitat: Forests and forest edge; may be found on the ground, but mostly arboreal, climbing several meters above in vegetation; frequently found along streams. It will also use second forest and agricultural areas.  Biology: Nocturnal. May spend daylight hours coiled in epiphytic plants or on the ground in leaf litter. Diet: snails and slugs; this snake is not as specialized as Dipsas for feeding on snails, but it does have elongated maxillary teeth directed medially in the horizontally plane, a character associated with gastropod predation. This is perhaps the most frequently encountered snake during the wet season.  Reproduction: Females lay 3−9 eggs from May through September. Predation by the crab Eudaniela garmani has been reported. 

Brown Vine Snake, Oxybelis aeneus (Family Colubridae)

Size: 1010 mm SVL, 1668 mm TL, may reach 2 m; hatchlings 200 mm; tail 54-77% SVL. Identification: A slender, vine snake with a sharply pointed snout, no loreal scale, 17 scale rows at mid-body, reduced to 13 scale rows posteriorly, and a uniform gray-brown dorsal pattern. Other Trinidad and Tobago vine snakes (genus Leptophis) have 15 scale rows at mid-body and a loreal scale and while Imantodes has 17 scale rows at mid-body, it has a blunt head, a blotched pattern and an enlarged row of vertebral scales. Rostral not visible from above; nasals single; one or two preocular; one to three postoculars; 7−9 upper labials,7−9 lower labials; ventrals 179−192; divided cloacal plate; divided subcaudals 171−192 in males 156-181 in females; dorsal scales smooth. Distribution: Widespread in the Neotropics, present on Trinidad and Tobago. Habitat: An arboreal, forest and forest-edge snake that uses scrub and agricultural areas. It sleeps off the ground on the vegetation. Biology: Diurnal. Diet is mostly lizards, but frogs and small birds are also eaten. Reproduction: Clutches of 3–6 eggs are laid in May-June.

False Coral Snake, Oxyrhopus petolarius (Family Dipsadidae)

Size: 725 mm TL, maximum total length about 1.1 m. Identification: Rostral barely visible from above; nasal single; loreal elongate and single; one or two preoculars; two postoculars; 7–8 upper labials; 8–9 lower labials; 199–204 ventrals; cloacal plate single; 81–86 subcaudals. Dorsal scales smooth in 19 rows (occasionally 17) at midbody. Most specimens black with red annuli which do not extend onto the venter, however may be uniform black, may also have crossbars reduced to large spots; venter uniform cream. The only T&T snake with 19 (or 17) rows of smooth dorsal scales, a single cloacal plate, a single nasal, and usually a banded pattern of red and black, but may be entirely black on dorsum. Hatchlings completely red with a black head. Habitat: Forest, savanna, secondary growth. Biology: Nocturnal. Diet includes small mammals, lizards, and snakes. Reproduction: Clutches of 5–10 eggs.

Coffee Snake, Ninia atrata (Family Dipsadidae)

Size: 300 mm SVL, 85 mm tail; may reach 490 mm in total length. Identification: The only Trinidad and Tobago snake with a collar making and uniform blue-black color pattern on the dorsum; the venter is immaculate. The collar may be orange, white, or pink, and it may be absent in some specimens, particularly old adults. Scales are keeled and in 19 rows. Rostral visible from above; nasal single; loreal single; preocular absent (fused with loreal); one postoculars; six or seven upper labials; six or seven lower labials; ventrals 147−158; cloacal plate single; 48−59 paired subcaudals. Distribution: A widespread snake, ranging from Honduras and Costa Rica to Ecuador and Venezuela. It also occurs on Trinidad and Tobago and the species is widespread on both islands. Habitat: Forests, urban gardens from sea level to the highest peaks on the islands. Biology: Nocturnal. Diet includes slugs (gastropods). Predators include coral snakes. Other common names: collared snake, ring neck snake, white-collared snake