Tobago is a small island on the southeast edge of the Caribbean Plate with a continental flora and fauna. Using DNA sequences from Genbank, new sequences, and morphological data from the snakes Erythrolamprus epinephalus, E. melanotus, E. reginae, and E. zweifeli, the species status of specimens of a Tobago snake previously considered to be Erythrolamprus reginae was assessed. Erythrolamprus zweifeli, long considered a subspecies of E. reginae, was found to be a northern Venezuela-Trinidad endemic and the sister to E. reginae. The trans-Andean species E. epinephalus is shown to be non-monophyletic while the Costa Rican lineage of E. epinephalus is weakly supported as the sister to the Tobago population. The Tobago Erythrolamprus is described as a distinct taxon based upon five specimens from four localities in lower montane rainforest. Much of the new species range includes the Main Ridge Forest Reserve of Tobago, the oldest protected forest in the Western Hemisphere. All known locations fall within a 400-ha area, and its total geographic distribution is likely to be less than 4,566 ha. The restricted distribution of this new snake makes it a likely candidate for threatened status. The new species also becomes another biogeographic link between northern Venezuela and Tobago.

cryptic species, evolutionary species concept, lowland montane rainforest, sky islands, systematics

The Cordillera de Costa (CC) is a sky island archipelago that extends 925 km in an east-west orientation from western Venezuela, across the Northern Range of Trinidad to the island of Tobago. The CC is separated from the Andes by the Yaracuy River depression, and in the east, the CC is separated from the Guyana shield by the Llanos grasslands. The Gulf of Paria separates the Peninsula de Paria from Trinidad, and Trinidad is separated by 35 km of open water from Tobago. The CC formed between the late Cretaceous and the Miocene (Sisson et al. 2005). Rising and falling sea levels, marine incursions, changing climates, and tectonic events have continually remodeled the landscape isolating and reconnecting populations of organisms.

Tobago is at the eastern edge of the CC sky island complex and is slightly more than 300 km², and its highest peak is about 576 m above sea level (ASL). The island has two physiographic regions: a flat coastal plain composed of a coral terrace in the southwest and the Main Ridge, a mass of metamorphic and igneous rocks, covered by dense tropical forest. The Main Ridge runs in a northeast-southwest direction.

Tobago’s snake fauna contains 23 species, and eleven of these belong to the Dipsadidae clade. Molecular studies on the Western Hemisphere snake clade Dipsadidae (or Dipsadinae) (Zaher et al. 2009; Vidal et al. 2010; Grazziotin et al. 2012) suggest Erythrolamprus Boie 1826 is not monophyletic unless most of the snakes formerly placed in the genera Liophis Wagler, 1830, Leimadophis Fitzinger, 1843, and Umbrivaga Roze, 1964 are included. This action increased the number of Erythrolamprus species from six, mostly coral snake mimics, to 50 species (Uetz and Jacob 2018) with a variety of color patterns and habits. Thus, Erythrolamprus became one of the most species-rich genera of Neotropical snakes. This arrangement has not been accepted by everyone (Wallach et al. 2014). Here we consider the genus Erythrolamprus in the broadest sense, including the species traditionally allocated to Leimadophis, Liophis, and Umbrivaga, acknowledging that future taxonomic changes are likely.

There is no known synapomorphy for the genus Erythrolamprus (Myers 2011). That said, members of the genus are usually less than 1.6 m in total length; nine scales are normally present on the crown; the number of dorsal scale rows is 15–19 and in some species they are reduced once, in others, they may be reduced twice posteriorly; apical pits may be present or absent on some or all of the scales; ventral counts range from 129–212; subcaudal counts range from 38–106; the temporal formula is usually 1+2; the preocular is usually single; the postoculars are usually two; upper labials are usually eight; lower labials are usually ten, and two pair of enlarged chin shields are present. Erythrolamprus ranges from Costa Rica southward to Argentina and occurs on both sides of the Andes as well as in the Lesser Antilles. Some taxa reach an elevation of 3,500 m ASL. Members of the genus have life styles that range from fossorial to terrestrial to semi-aquatic in habitats spanning rainforests, savannas, and páramo (Savage 2002).

Museum material examined (Appendix 1) included 105 specimens of five Erythrolamprus species. Snakes were examined for external morphological data; scale nomenclature follows Dixon (1983a, b). Museum acronyms are as follows:

AMNH American Museum of Natural History

FMNH Field Museum of Natural History

EBRG Museo de la Estación Biológica de Rancho Grande

UMMZ University of Michigan Museum of Zoology

USNM National Museum of Natural History

UWIZM University of the West Indies Zoology Museum

MBLUZ Museo de Biología, Universidad del Zulia

MCNC Museo de Ciencias Naturales, Caracas

Locality data was converted into coordinates using Google Earth. Measurements of the body and tail lengths were taken to the nearest millimeter; ventral scale count methods follow Dowling (1951). The anal plate and terminal scutes were not included in the number of ventrals or subcaudals. The dorsal scale row counts were made about ten ventrals behind the head, at mid-body, and about ten ventrals anterior to the vent. Values for paired head scales are given in left/right order. Scales were measured to the nearest 0.1 mm with the aid of a digital caliper and dissection microscope. Total length (TTL) and tail length (TL) measurements were taken to the nearest mm by carefully stretching the specimens along a ruler or placing a measuring tape along the length of the animal (Appendix 2). Statistical analyses were done with Excel-QI Macros (alpha = 0.05). Ventral and subcaudal counts were compared using ANOVA (Appendix 3).

DNA extraction, purification, and amplification protocols follow Jowers et al. (2013). Two mitochondrial gene fragments, 12S rDNA (primers 12Sa and 12Sb; Kocher et al. 1989), 16S rDNA (primers 16SL and 16SH; Palumbi 1996) and a nuclear gene fragment, c-mos (primers G73 and G74; Saint et al. 1998) were amplified. The lengths of the sequences were: 12S rDNA, 343 base pairs (bp); 16S rDNA, 425 bp; c-mos, 564 bp. We sequenced four Erythrolamprus melanotus (GenBank accession numbers are shown in Appendix 4) from Trinidad (n = 1), Tobago (n = 3), two E. zweifeli from Trinidad, and a new undescribed Erythrolamprus sp. from Tobago. We downloaded all Erythrolamprus sequences for the same loci from Genbank and used Xenodon histricus as the outgroup (Hodson and Lehtinen 2017).

Seaview v.4.2.11 (Gouy 2010) was used for preliminary alignments of sequences and were aligned thereafter in MAFFT (Katoh et al. 2002), and phylogenetic analyses were conducted using the concatenated mitochondrial and nuclear (12S+16S rDNA+c-mos) alignment (with a length of 1332 bp) using a partitioned model of substitution by gene fragment. The most appropriate substitution model for each gene partition was determined by the Bayesian Information Criterion (BIC) in PartitionFinder v.2 (Lanfear 2012). The best-fitting models for the ribosomal and c-mos fragments were as follows: 12S rDNA + 16S rDNA (TRN+I+G), c-mos first and second codon positions (TrNef+I) and c-mos third codon position (HKY). Phylogenetic relationships between taxa were inferred using the Bayesian Inference (BI) optimality criterion under the best fitting substitution model for each gene partition. MrBayes Huelsenbeck et al. (2001) was used with default priors and Markov chain settings, and with random starting trees. Each run consisted of four chains of 30 million generations, sampled every 1,000 generations. Runs were evaluated for convergence and mixing by observing and comparing traces of each parameter in Tracer v.1.6 (http://beast.bio.ed.ac.uk/tracer) (Rambaut et al. 2014). We considered effective sampling size (ESS) values > 200 to be good indicators of parameter mixing. Phylogenetic relationships (Figure 1) were also estimated using a Maximum Likelihood (ML) approach, as implemented in the software RAxML v7.0.4 (Silvestro and Michalak 2010), under the best partition scheme under the GTR model. All analyses were performed using the CIPRES platform (Miller et al. 2010). P-uncorrected distances were calculated in MEGA V7 (Kumar et al. 2016) under complete deletion of gaps and missing data.

Figure 1. 

Bayesian inference tree of Erythrolamprus species from Genbank MtDNA 12S+16SrDNA+c-mos sequences (1332 bp). Red stars indicate Bayesian inference and ML posterior probabilities (> 95%) and bootstrap (> 70%) support values above and below nodes, respectively. Clade in orange shows E. zweifeli, in green E. melanotus, and in blue E. pseudoreginae sp. n. (AF158433) is from French Guiana, and E. reginae (JQ598983) is from Brazil.

Morphological results

Figure 2 shows the similarities in the architecture of the scales when Erythrolamprus are viewed in profile. They all have a single preocular, two postoculars, and eight upper labials; the second and third upper labials are in contact with the loreal, the fourth and fifth border the orbit, and the temporal formula is 1+2. Figure 3 compares the crowns and chins of four of these species (including E. zweifeli from three different populations). They all share nine plate-like scales on the crown in similar proportions and two pair of enlarged chin-shields. Figure 4 illustrates the distribution of the five species in northern South America, Trinidad, and Tobago.

Figure 2. 

A comparison of the five members of the Erythrolamprus reginae group. A E. reginae for Guyana (FMNH 30959) B E. zweifeli from Venezuela (FMNH 204477) C E. melanotus from Tobago (UWIZM.2012.42.19) D E. pseudoreginae sp. n. from Tobago (FLMNH 91621) E E. epinephalus from Venezuela (MBLUZ 1502).

Figure 3. 

A comparison of the scale arrangements on the crowns and ventral heads of the Erythrolamprus taxa under discussion. A E. pseudoreginae sp. n. from Tobago B E. epinephalus from Venezuela MBLUZ 1501 (dorsal view) and 1500 (ventral view) C, D Salt and pepper morph of E. zweifeli from Trinidad and Venezuela E An olive-brown morph of E. zweifeli Trinidad, FMNH 215827 F A melanistic morph of E. zweifeli from Venezuela EBRG 2745.

Figure 4. 

Geographic distribution of the five species of Erythrolamprus under discussion in this paper. A The distribution of the species of Erythrolamprus under discussion in northern Venezuela and Trinidad and Tobago B More detailed view of the distribution on Trinidad and Tobago C Tobago with the known localities for E. pseudoreginae sp. n. Note that two of the markers closely overlap. Key: black stars = E. zweifeli from Cordillera de Costa in Venezuela and the island of Trinidad; green circles = E. epinephalus from the Cordillera de Mérida, Venezuela. Note that these markers denote the closest population to Tobago based on Roze (1966). Specimens examined came from several different locations. Purple stars = E. reginae from the Guianas including Orinoco Delta in Venezuela; red stars = E. melanotus from Venezuela, Trinidad, and Tobago; blue star = Erythrolamprus pseudoreginae sp. n. on Tobago.

Comparisons and summaries of the meristic characters for taxa under consideration are given in Table 1. Ventral counts for all Erythrolamprus taxa under consideration have ranges that overlap, although they have different means, some of which are significantly different. The ranges for the subcaudal counts are similar. The Tobago E. pseudoreginae sp. n. can be separated from E. melanotus but not the other taxa. The results of single factor ANOVAs are presented in Appendix 2. Some support the separation of E. zweifeli from E. reginae, E. zweifeli from the Tobago E. pseudoreginae sp. n., and E. reginae from the Tobago E. pseudoreginae sp. n.

Table 1.

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A comparison of the meristic and color pattern data for the five taxa in Erythrolamprus in the Trinidad and Tobago area. Key: * based on our counts for Venezuelan specimens.

	E. melanotus	E. reginae	E. zweifeli	E. pseudoreginae sp. n.	E. epinephalus
Number of specimens	12	14	44	5	6
stripe on rows	4–5	3–4	3–4	3–4–5	variable
ventral range	139–154	129–147	134–157	143–154	144–157*
mean ventrals ± SD	146.66 ± 4.36	138.35 ± 4.71	142.54 ± 3.98	147.5 ± 3.35	151.33 ± 3.38
subcaudal range	53–58	68–79	72–85	76–79	65–75*
mean subcaudals ± SD	55.2 ± 1.4	72.0 ± 7.14	79.9 ± 4.20	77.5 ± 1.5	68.2 ± 3.38
postocular stripe	present	indistinct	present	indistinct	variable
ventral color	yellow	yellow to pale orange, usually with black checks	red with black checks, some ventrals solid black	uniform yellow to red with scattered fine speckling	variable
apical pit present	yes	yes	no	yes	yes

Substantial genetic differences (0.047) (Appendix 5) and relatively minor morphological differences (different means for ventral counts, distinctive coloration, the absence of apical pits on dorsal scales) and its geographic isolation support the description of the Tobago population as a new species. Figure 5 compares the color morphs of Erythrolamprus zweifeli found in Trinidad and Venezuela with Erythrolamprus reginae from Guyana. Figure 6 illustrates E. pseudoreginae sp. n.

Figure 5. 

A, B Variations in the olive color morph of Erythrolamprus zweifeli from Trinidad (photographs by Michael Patrikeev) C the middle photo shows the “salt and pepper” morph that occurs at higher elevation (photograph by JCM). Both color morphs are included in our molecular sample D E. zweifeli Rancho Grande, Parque Nacional Henri Pittier, Luis A. Rodriguez J. E the Royal Snake, Erythrolamprus reginae from Kaiteur, Guyana (photograph by P Kok).

Figure 6. 

Erythrolamprus pseudoreginae. AUWIZM 2016.22.45, holotype B–D FLMNH 91621 from Gilpin Trace, on Tobago’s Main Ridge. B Profile. Of the four specimens examined this was the only one that had nine upper labials (on one side only) C The posterior lateral stripe bordered by a dorsal light stripe D Venter mostly uniform with patches of scattered pigment.

Erythrolamprus pseudoreginae sp. n.

http://zoobank.org/B5FAE467-C240-4EBB-9DA5-B3D44998757E

Figures 2D, 3A, 6

Liophis sp. Hardy 1982: 86.

Liophis reginae [ssp.] Dixon 1983b: 12.

Material

Holotype.UWIZM.2016.22.45 collected 13 June 2016 by Alvin L. Braswell and Renoir J. Auguste on Gilpin Trace Trail, 8.5 km NNW Roxborough, St. John, Tobago (~11°16'55"N; 60°37'12"W, about 493 m ASL) at 0900 hrs. Paratypes. TOBAGO: St John: FLMNH 91621 Gilpin Trace Trail, 5.3 mi NNW Roxborough, 11°16'N, 60°37'W collected on 17 July by Kurt Auffenberg. USNM 228069 south of Charlotteville, at first creek crossing on Pigeon Peak Trace 11°17'N, 60°36'W collected 12 May 1979 at (14:00 hrs) by Dave Stephens; USNM 325089 NW of Roxborough on Gilpin Trace, ca. 0.5 mi from its junction with Roxborough-Bloody Bay Road, collected 11 November 1992; USNM 539191 approx. 6 km (airline) NNW of Roxborough, 0.5 mi from upper entrance of Gilpin Trace and Roxborough - Parlatuvier Road, 11°17'N, 60°35'W collected 11 July 2000.

Diagnosis

Ventrals 143–154; subcaudals 76–79; second pair of chin shields longest; some anterior dorsal scales have an apical pit; lateral stripe on scale rows 3–4–5, dark stripe (row 3) and a pale stripe (rows 4–5) on posterior body and tail, the black stripe continues to the forebody as a series of black spots on scale row three; and the ventral surface has scattered flecks of pigment toward mid-body. Otherwise, the belly is uniform cream with fine speckling in preserved material, and red in life, tail uniform cream in preservative, red in life.

Description of the holotype

UWIZM.2016.22.45, an adult male, 525 mm total length, 148 mm tail; tail 28% of SVL. Rostral barely visible from above, broader than tall; internasals paired, shorter than prefrontal; frontal pentagonal; parietals longer than frontal; four post parietals; nasal divided, first lobe does contact the second labial; loreal subrectangular, higher than long, contacts upper labials 2–3; preocular single, T-shaped, contacts upper labials 3–4; postoculars 2/2, upper largest; temporals 1+2, primary temporal contacts upper labials 6–7/6–7; upper labials 8/8; 4–5 in orbit; lower labials 4/5 contact anterior chin shields, total of nine in contact with both pairs; lower labials 9/10; three gular scales; dorsal scales are smooth, some have a single apical pit, they are in 17 rows at mid body and reduced to 15 rows anterior to the cloaca; 146 ventrals; 77 subcaudals.

In life the crown is dark moss green with black spots, the upper labials are cream, with a dark stripe on the upper edge that runs from nasal to orbit, and widens posteriorly onto the temporals. Dorsal spots on scale rows 2–3 about two ventrals apart, start above the 12^th ventral, and coalesce into a stripe at about the 96^th ventral and extend posteriorly to the tip of the tail; lateral stripe mostly on scale row three on body, goes onto scale row one on tail. About one-third down the body, about ventral 40, scale rows 1−4 blue-gray, row five is brown, row six and above blue-gray; except for the mossy green on the anteriormost dorsal surface for about 40 ventrals. Ventral surface mostly uniform yellow to orange with light mottling starting about the 50^th ventral; tail has a mid-line zigzag stripe.

Variation: The smallest specimen measured 347 mm SVL with a 129 mm tail; the largest specimen 420 mm SVL with a 119 mm damaged tail. Dorsal scale rows 17–17–15. Ventrals range from 143–154 (n = 5, X = 147.5, SD = 3.35); subcaudals 76–79 (n = 2, X = 77.5, SD = 1.5). Upper labials eight or nine, 2–3 contact loreal, 4–5 border the orbit (one specimen has 5–6 bordering the orbit on one side), the tallest can be seventh, (or eight if nine labials are present); the sixth labial is the largest in the area. Loreal is quadrangular to pentagonal. Lower labials 9–10; first four or five contact the anterior chin shields. Longest pair of chin shields is the second. Eye diameter is greater than eye-nostril distance. The dark posterior lateral stripe is usually on scale rows 2–3–4, but one specimen has it on scale rows 2–3 only.

Color in life. The following is based on the holotype (Figure 6) and a color photograph in Brown (2013). Crown and face olive brown, upper labials white, a short black subocular stripe extends from the nasal scale under the eye and posteriorly to the last labial. Immediately behind the head, the interstitial skin is yellow; dorsum brown with an indistinct vertebral stripe and scales partially edged with black pigment most obvious on posterior two-thirds of the body. First three scale rows are blue-gray and separated from brown dorsum by a row of black spots.

Color in alcohol. Head, body, and tail dark blue to brown with a black stripe on the posterior lateral body that becomes a series of dark spots extending anteriorly on the body. The belly is a uniform cream with fine speckling of pigment.

Comparisons

Erythrolamprus pseudoreginae sp. n. differs from E. zweifeli in the presence of apical pits on some dorsal scales, an almost uniform yellow to red venter, and a dark stripe on the posterior body on scale rows 3–4 bordered above by a pale stripe on scale row five. The new species lacks the well-defined postocular stripe that runs from the postocular scales across the temporals to a point just above the rictus in most E. zweifeli. In E. zweifeli the postocular stripe may also have a pale dorsal border.

Erythrolamprus pseudoreginae sp. n. differs from all populations of E. epinephalus in having more than 75 subcaudal scales, except for some Venezuelan and Colombian populations. The E. epinephalus populations with more than 75 subcaudals have a dorsal or ventral pattern that includes transverse bars, black checks, or a pattern with irregular black spots on the outer edges of the ventral scales that may extend onto the first row of dorsal scales (Dixon 1983a, Escalona 2017).

The new species differs from Erythrolamprus reginae in having a uniform venter (E. reginae) has yellow to orange venter with black checks, and a dark stripe on the last fourth of the body on scale rows 3–4 which is not bordered by a pale stripe. Erythrolamprus pseudoreginae sp. n. has uniform yellow to red ventral surface and a very distinctive, pale posterior lateral stripe on row five above the black stripe on rows 3–4 that extends anteriorly as a row of dark spots. Erythrolamprus reginae has fewer ventrals and a lower mean ventral count than E. pseudoreginae sp. n.

The pattern will readily distinguish it from the two coral snake mimics (Erythrolamprus aesculapii and E. bizona) which are on Trinidad but not Tobago. The endemic Tobago Red Snake, E. ocellatus, has a bright red dorsum with black ocelli. The semi-aquatic Erythrolamprus cobellus has a uniform dark green or black dorsum and is known from Trinidad but not Tobago. The absence of a black stripe five scale rows wide on the vertebral line separates it from Shaw’s Black Back Snake, E. melanotus, a species known from both islands.

Distribution

It occurs in northeastern Tobago and appears to be restricted to the forested ravines along the crest of the Main Ridge (Fig. 4). Tobago’s Main Ridge is about 16 km long and covered with lower montane rain forest on schist soil above 224 m ASL. The ridge crest reaches elevations of 487–576 m ASL and forms steep terrain with deep gullies and fast-moving streams. The area receives about 318 cm of rainfall per year, and no month receives less than 10 cm (Beard, 1944). Tobago’s Main Ridge Forest Reserve is the oldest protected forest in the Western Hemisphere (since April 1776) and encompasses 3958 hectares. At this writing, five specimens of Erythrolamprus pseudoreginae sp. n. are known, all of which came from the northeast end of the Main Ridge. The locality and elevation data available suggest it occurs within an area of about 400 ha at elevations between 430–500 m ASL. Three types of rainforest occur on Tobago: lowland rainforest covers 4,844 ha, lower montane rainforest covers 4,566 ha, and xerophytic rainforest covers 937 ha (Helmer et al. 2012). All of the localities for E. pseudoreginae sp. n. fall within the lower montane rainforest, suggesting its maximum area of occupancy may be 4,566 ha, if it is restricted to that forest type.

Natural History

Erythrolamprus pseudoreginae sp. n. is diurnal, all of the specimens with time of collection data were found in the morning or afternoon. Nothing is known about the diet and reproduction of this snake. Its close relatives have been reported to eat anurans, and it likely preys upon small ground-dwelling frogs.

Conservation

Given the restricted distribution of this snake as well as the fact that most, if not all, of its distribution lies within the oldest protected forests in the Western Hemisphere it may be assumed that it is well protected. However, as the climate changes the microclimate found in the lowland montane rainforest may be expected to change and potentially make the local environment inhospitable for this species and the other endemic taxa found here.

Etymology

The epithet pseudoreginae was chosen because prior investigators considered this snake to be Liophis reginae. We suggest Tobago Stream Snake as the common English name for this snake.

Erythrolamprus pseudoreginae becomes the fifty-first species in the genus, and the eleventh member of the Tobago herpetofauna closely associated with the Main Ridge. The list of Main Ridge species includes the frogs Mannophryne olmonae, Pristimantis charlottevillensis, P. turpinorum, Hyalinobatrachium orientale; the lizards Bachia cf. flavescens, Gonatodes ocellatus, Anolis cf. tigrinus; and the snakes Atractus fuliginosus, Erythrolamprus ocellatus, and Leptophis haileyi.

Most of the Main Ridge endemic species seem to have their closest living relatives in the Costal Ranges of Venezuela as opposed to the more proximal island of Trinidad or the Guiana Shield. The Coastal Range endemic Mannophryne riveroi is the sister to M. olmonae (Manzanilla et al. 2009, Lehtinen et al. 2011). Tobago’s Pristimantis charlottevillensis appears to be most closely related to P. terraebolivaris and members of the Pristimantis conspicillatus group (Hedges et al. 2008). Jowers et al. (2015) proposed a Pliocene land bridge connection between Tobago and Venezuela to explain the presence of Hyalinobatrachium orientale on Tobago and northeast Venezuela. An alternative explanation is that Tobago was accreted to Venezuela on its movement to its current position.

With this study, only 21 of the 51 named Erythrolamprus species have been included in molecular studies; thus, the tree contains only 41% of the known species in the genus. Therefore, its topography is likely to change with additional taxa from more locations. Erythrolamprus reginae and E. epinephalus are polytypic and given their distributions and morphological variation they represent a considerable challenge to resolving the lineages found within these taxa. Some of the color patterns have evolved multiple times in the different lineages and when combined with the conserved morphology, separating these taxa by morphology becomes a conundrum. It seems likely that some of the currently recognized subspecies will be found more closely related to lineages other than the one they are currently assigned.

The phylogenetic analyses suggest part of E. reginae is the sister to E. zweifeli. The results show for the first time the Trinidadian E. melanotus, has no genetic divergence from the most common haplotype from Tobago. This lack of differentiation suggests some recent or ongoing gene flow between islands. The position of E. ocellatus from Tobago suggests that it forms a highly divergent lineage to the remaining Tobago´s Erythrolamprus and may indicate a different time of colonization.

We would like to thank all of the institutions and curators who provided us with specimens, work space, and literature resources: American Museum of Natural History (AMNH), David Kizirian; Museo de la Estación Biológica de Rancho Grande (EBRG), Edward Camargo; Florida Museum of Natural History (FLMNH), Max Nickerson, Kenneth Krysto; Field Museum of Natural History (FMNH), Alan Resetar; Milwaukee Public Museum (MPM), Robert W. Henderson; University of Michigan Museum of Zoology (UMMZ), Greg Schneider; National Museum of Natural History (USNM), Jeremy Jacobs, Kevin de Queiroz, Kenneth Tighe, Robert Wilson; Museo de Ciencias Naturales, Caracas (MCNC), Hyram Moreno; University of the West Indies Museum of Zoology (UWIZM) Mike G. Rutherford. Luis A. Rodríguez J. (serpientesdevenezuela.net) provided photos of E. epinephalus from Venezuela We would also like to offer our sincerest thanks to Tom Anton and Gabriel Haas for lab and field assistance and Nathalie Aall for Figure 1. The field work and collecting was done under permits from the Wildlife Section Forestry Division in St Joseph, Trinidad issued to John C Murphy, Richard M Lehtinen, and Mike G Rutherford and permits from the Tobago House of Assembly in Scarborough, Tobago issued to Mike G Rutherford and John C Murphy between the years 2010 and 2017.