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A new species of Erythrolamprus from the oceanic island of Tobago (Squamata, Dipsadidae)
expand article infoJohn C. Murphy, Alvin L. Braswell§, Stevland P. Charles|, Renoir J. Auguste, Gilson A. Rivas#, Amaël Borzée¤¤, Richard M. Lehtinen«, Michael J. Jowers»˄
‡ Field Museum of Natural History, Chicago, United States of America
§ North Carolina State Museum of Natural Sciences, Raleigh, United States of America
| Howard University, Washington, United States of America
¶ University of the West Indies, St. Augustine, Trinidad and Tobago
# Universidad del Zulia, Maracaibo, Venezuela
¤ Ewha Womans University, Seoul, Korea, South
« Department of Biology, The College of Wooster, Wooster, United States of America
» Universidade do Porto, Vairão, Portugal
˄ National Institute of Ecology, Geumgang-ro, Korea, South
Open Access

Abstract

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.

Keywords

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

Introduction

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).

The genus Erythrolamprus in the Cordillera de la Costa

Eighteen species of Erythrolamprus occur in northern Venezuela, of these, two are Pantepui species: E. trebbaui (Roze 1958a), E. ingeri (Roze 1958b). The remaining 16 species are associated with the CC either as montane species, lowland species, or species that are not restricted by elevation. Eight of the 16 species occur on the Guyana Shield and seven species of Erythrolamprus are recognized on Trinidad and Tobago: E. aesculapii (Linnaeus, 1758); E. bizona Jan 1863; E. cobellus (Linnaeus, 1758); E. melanotus (Shaw, 1802), E. ocellatus Peters, 1868; E. zweifeli (Roze, 1959); and E. reginae (Linnaeus, 1758) (Murphy et al. 2018). Both E. aesculapii and E. bizona are coral snake mimics, and each is known from a single specimen from Trinidad (but better known from elsewhere in their ranges).

Erythrolamprus ocellatus is a Tobago endemic, with a bright red dorsum and black ocelli, and is best considered an imperfect coral snake mimic, keeping in mind that there are no extant species of coral snakes on Tobago (Hodson and Lehtinen 2017). Erythrolamprus cobellus is a semi-aquatic, lowland species; while E. melanotus and E. zweifeli are forest species often associated with stream-edge habitats and mountains from sea level to at least 2,000 m. However, in Venezuela, E. zweifeli is usually associated with montane environments.

Noting significant differences in coloration, as well as distinct ventral and subcaudal counts from E. reginae, Rivas et al. (2012) returned Erythrolamprus reginae zweifeli to species status. They noted E. zweifeli differs from E. reginae in having a salt-and-pepper dorsal pattern or a more uniform olive-green or olive-brown pattern. Wallach et al. (2014) concurred and recognized the elevation of zweifeli to species level. E. reginae has a dorsum with dense pale and dark paravertebral flecking. The two species also differ in subcaudal counts (69−88 in E. zweifeli as opposed to 55−78 in E. reginae) with the ranges overlapping, but different means. Following this arrangement, E. zweifeli occurs throughout the Cordillera de Mérida and the CC in Venezuela, including Trinidad.

Natural history of Trinidad and Tobago´s Erythrolamprus

There are some ecological differences between the Trinidad and Tobago Erythrolamprus. The two poorly known coral snake mimics (E. aesculapii, E. bizona) are forest dwellers and snake predators (Campbell and Lamar 2004). Dietary differences between the two better known forest and forest-edge species are apparent. Erythrolamprus melanotus feeds on the microteiid lizards in the genus Bachia, the rain frog Pristimantis urichi, the puddle frog Engystomops pustulosus and the gecko Gonatodes vittatus, and unidentified fish have been reported. Erythrolamprus zweifeli feeds on stream frogs of the genus Mannophryne, hylid frogs, Leptodactylus validus, salamanders, lizards of the genus Ameiva, and small birds (Michaud and Dixon 1989; Murphy 1997; Esqueda et al. 2009). While the diets overlap the presence of Bachia, Gonatodes, and Pristimantis urichi in the diet of E. melanotus suggest it is hunting in more terrestrial situations in forests or at forest edges. Mannophryne in the diet of E. zweifeli suggests it is hunting along forested stream-edges. It supports the fact that E. zweifeli was the most common snake encountered during a study in a canal system used for water collection from a mountain stream located in Naiguatá, Venezuela (Silva et al. 1985; Silva and Valdez 1989).

Erythrolamprus epinephalus (Cope, 1862) is widespread and polytypic, ranging from Costa Rica to Ecuador, Colombia, and Venezuela and has not been previously associated with Trinidad or Tobago. The examination of a single specimen (USNM 22069) from Tobago led Dixon (1983b) to conclude that it was Liophis (= Erythrolamprus) reginae with an atypical color pattern that resembled a Liophis (= Erythrolamprus) epinephalus population from eastern Colombia. Dixon’s remark was the only mention of E. epinephalus associated with Trinidad and Tobago. He noted the most striking difference in the Tobago animal was a dorsolateral tan stripe not present in the Trinidadian E. zweifeli.

Here, we examine the genetic divergence and morphology of a Tobago snake, previously considered part of the E. reginae group, in an attempt to understand its phylogenetic relationship to other Erythrolamprus and the biogeography in northeastern South America.

Materials and methods

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.

Molecular results

Runs showed high Effective Sample Size convergence (> 2300), indicating adequate sampling of the posterior distribution. The p-uncorrected distances between L. epinephalus from Costa Rica and E. sp. from Tobago were the highest of all terminal monophyletic clades (4.69%) indicating the high genetic divergence between both species (Appendix 5). The phylogenetic relationships of Erythrolamprus and the paraphyly of some species (E. typhlus, E. poecilogyrus, E. epinephalus, E. aesculapii) are similar to past published work (Hodson and Lehtinen 2017), suggesting the need for an in-depth systematic revision of the genus. Furthermore, the results show the paraphyly of Erythrolamprus reginae. Erythrolamprus melanotus from Trinidad and Tobago are monophyletic, and the Trinidad specimen shows no genetic differentiation from the most common Tobago haplotype. Erythrolamprus sp. from Tobago is the sister clade to E. epinephalus from Costa Rica. This clade, composed by the three species (E. melanotus + E. epinephalus+E. sp. Tobago), is strongly supported in the Bayesian analyses. The Trinidadian E. zweifeli form the sister clade to E. reginae from Guyana but are a distinct lineage.

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.

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. A UWIZM 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.

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 12th ventral, and coalesce into a stripe at about the 96th 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 50th 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.

Discussion

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.

Acknowledgements

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.

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Appendix 1

Locality data for specimens examined in this study. Coordinates represent georeferencing from Google Earth, variation from the exact collecting locality is expected.

Species Voucher Country Coordinates
epinephalus MBLUZ 1500 Venezuela 10°19'N; 72°35'W
MBLUZ 1501 Venezuela 10°19'N; 72°35'W
MBLUZ 1502 Venezuela 10°19'N; 72°35'W
MBLUZ 1503 Venezuela 10°19'N; 72°35'W
MCNC 5677 Venezuela 07°39'N; 72°21'W
MCNC 7875 Venezuela 07°29'N; 72°27'W
melanotus FMNH 61669 Colombia 07°09'N; 75°21'W
FMNH 61670 Colombia no specific locality
FMNH 121224 Colombia 04°09'N; 73°38'W
FMNH 165341 Colombia 10°26'N; 75°22'W
FMNH 165399-408 Colombia 10°26'N; 75°22'W
FMNH 165498 Colombia 10°26'N; 75°22'W
FMNH 165644 Colombia 10°26'N; 75°22'W
FMNH 165645 Colombia 10°26'N; 75°22'W
FMNH 217232 Trinidad 10°43'N; 61°17'W
FMNH 218779 Trinidad 10°43'N; 61°17'W
FMNH 49947-50 Trinidad 10°29'N; 61°28'W
FMNH 49945-46 Trinidad 10°16'N; 61°1'W
FMNH 5674 Trinidad 10°39'N; 61°30'W
FMNH 77902-03 Trinidad 10°39'N; 61°30'W
FMNH 190749 Trinidad 10°09'N; 61°30'W
FMNH 49938-44 Trinidad 10°34'N; 61°15'W
FMNH 69778 Venezuela 10°28'N; 67°07'W
reginae AMNH 3595 “Guiana” no specific locality
USNM 164210 Guyana 8°12'N; 59°46'W
USNM 164208 Guyana 8°12'N; 59°46'W
FMNH 30959 Guyana 10°29'N; 61°28'W
FMNH 30962 Guyana no specific locality
UMMZ 53901 Guyana no specific locality
UMMZ53912 Guyana no specific locality
UMMZ 53968 Guyana no specific locality
UMMZ 53969 Guyana no specific locality
AMNH 17680 Guyana 6°47'N; 58°09'W
FMNH 56149 Peru 4°36'S; 74°10'W
FMNH 40234 Peru 11°48'S; 70°48'W
AMNH 8132 Suriname 5°51'N; 55°12'W
AMNH 4436 Venez. or Brazil no specific locality
pseudoreginae USNM 539191 Tobago 11°17'N; 60°35'W
UWIZM.2016.22.45 Tobago 11°17'N; 60°36'W
UWIZM 91621 Tobago 11°16'N; 60°37'W
USNM 325089 Tobago 11°17'N; 60°36'W
USNM 228069 Tobago 11°17'N; 60°36'W
Erythrolamprus sp. USNM 549328 Guyana 05°17'N; 60°45'W
zweifeli FMNH 215827 Trinidad 10°43'N; 61°17'W
FMNH 217226-27 Trinidad 10°43'N; 61°17'W
FMNH 219615 Trinidad 10°43'N; 61°17'W
USNM 17757-58 Trinidad 10°43'N; 61°17'W
FMNH 49957-58 Trinidad 10°28'N; 61°28'W
UWIMZ 2010.12.110 Trinidad 10°43'N; 61°25'W
UWIMZ 2010.12.201 Trinidad 10°45'N; 61°26'W
UWIMZ 2010.12.108a, b Trinidad 10°16'N; 61°1'W
UWIMZ 2010.12.107 Trinidad no specific locality
UWIMZ 2010.12.109 Trinidad no specific locality
USNM 252682-83 Trinidad 10°45'N; 61°17'W
USNM 286922 Trinidad 10°30'N; 61°16'W
AMNH 137503 Venezuela 10°01'N; 67°17'W
AMNH 98260 Venezuela 10°06'N; 63°06'W
USNM 217197 Venezuela 02°37'N; 66°19'W
FMNH 120986 Venezuela 10°01'N; 67°17'W
FMNH 204477 Venezuela 10°01'N; 67°17'W
UMMZ 124225 Venezuela 10°01'N; 67°17'W
UMMZ 124227-33 Venezuela 10°01'N; 67°17'W
UMMZ 128390 Venezuela 10°01'N; 67°17'W
USNM 217198 Venezuela 10°15'N; 68°21'W
USNM 196332 Venezuela 10°13'N; 66°25'W
AMNH 67877 Venezuela 10°06'N; 63°06'W
AMNH 29317 Venezuela 10°09'N; 64°17'W
AMNH 29332 Venezuela 10°29'N; 66°07'W
AMNH 29317 Venezuela 10°22'N; 63°17'W
FMNH 17833-36 Venezuela 10°22'N; 63°17'W
AMNH 29332 Venezuela 10°09'N; 64°17'W

Appendix 2

Morphometric data and sex for specimens of Erythrolamprus species examined. Key: m = male, f = female; j = juvenile; SVL = snout vent length mm; tail mm; D1–3 dorsal scale rows at anterior, midbody, and posterior body); V = ventral scales; S = subcaudal scales; nd = no data.

Museum Voucher Species Sex svl tail D1 D2 D3 V S
MBLUZ 1500 epinephalus ? 335 88 d 17 17 15 153 51+
MBLUZ 1501 epinephalus ? 330 112 17 17 15 155 75
MBLUZ 1502 epinephalus ? 280 95 17 17 15 153 69
MBLUZ 1503 epinephalus f 340 19 17 17 15 157 67
MCNC 5677 epinephalus m 355 112 17 17 15 144 65
MCNC 7875 epinephalus m 345 120 17 17 15 146 65
FMNH 165402 melanotus f 332 90 17 17 15 142 54
FMNH 49946 melanotus f 291 61 17 17 15 144 57
FMNH 49947 melanotus f 230 52 17 17 15 139 53
FMNH 49950 melanotus f 307 77 17 17 15 nd nd
FMNH 190749 melanotus f 305 72 17 17 15 142 54
FMNH 165644 melanotus m 358 92 17 17 15 149 55
FMNH 165498 melanotus m 325 97 17 17 15 144 54
FMNH 165407 melanotus m 350 85 17 17 15 147 55
FMNH 49949 melanotus m 271 76 17 17 15 147 56
FMNH 77903 melanotus m 275 76 17 16 15 152 58
FMNH 69778 melanotus m 370 72+ 17 17 15 154 nd
FMNH 121224 melanotus m 282 81 17 16 15 149 57
FMNH 61670 melanotus nd 310 81 17 17 15 151 55
AMNH 4436 reginae f 355 128 17 17 15 144 74
UMMZ 53912 reginae f 420 117 17 17 15 133 79
UMMZ 53969 reginae f 415 nd 17 17 15 136 nd
USNM 164210 reginae f 428 nd 17 17 15 139 nd
AMNH 3595 reginae f 443 nd 17 17 15 136 nd
FMNH 40234 reginae j 128 44 17 17 15 147 74
AMNH 17680 reginae m 313 120 17 17 15 137 73
AMNH 8132 reginae m 445 nd 17 17 15 142 nd
FMNH 30959 reginae m 443 d 17 17 15 139 nd
FMNH 56149 reginae m 419 117 17 17 15 145 55
UMMZ 53901 reginae m 428 186 17 17 15 139 78
UMMZ 53968 reginae m 474 210 17 17 15 135 75
USNM 164208 reginae m 308 nd 17 17 15 136 nd
FMNH 30962 reginae nd nd nd 17 17 15 129 68
USNM 539191 pseudoreginae f 408 nd 17 17 15 148 nd
USNM 228069 pseudoreginae f 347 129 17 17 15 143 76
USNM 539191 pseudoreginae f 408 nd 17 17 15 148 nd
FLMNH 91621 pseudoreginae m 420 119 17 17 15 146 nd
FLMNH 91621 pseudoreginae m 420 119 17 17 15 146 nd
USNM 325089 pseudoreginae m 408 158 17 17 15 154 79
USNM 549328 Erythrolamprus sp. m 361 117 17 17 15 148 64
AMNH 137503 zweifeli f 456 167 17 17 15 146 83
FMNH 17836 zweifeli f 380 165 17 17 15 138 82
FMNH 204477 zweifeli f 454 180 17 17 15 142 85
UMMZ 128390 zweifeli f nd nd 17 17 15 141 nd
UMMZ 124232 zweifeli f 375 144 17 17 15 144 nd
UMMZ 1288390 zweifeli f 402 162 17 17 15 141 84
USNM 17757 zweifeli f 471 187 17 17 15 143 76
USNM 252683 zweifeli f 236 nd 17 17 15 140 nd
USNM 217197 zweifeli f 434 167 17 17 15 134 72
USNM 252683 zweifeli f 236 nd 17 17 15 140 nd
UWIZM 2010.12.109 zweifeli f 245 nd 17 17 15 nd nd
UWIZM 2010.12.107 zweifeli f 355 152 17 17 15 139 79
UWIZM 2010.12.201 zweifeli f 401 158 17 17 15 143 79
UWIZM 2010.12.109 zweifeli f 245 nd 17 17 15 nd nd
FMNH 17833 zweifeli j 172 63 17 16 15 140 80
FMNH 17835 zweifeli j 152 56 17 17 15 144 85
UMMZ 124229 zweifeli j 305 117 17 17 15 139 83
UMMZ 124230 zweifeli j 184 67 17 17 15 141 80
UMMZ 124227 zweifeli j nd nd 17 17 15 142 84
UMMZ 124231 zweifeli j 185 62 17 17 15 145 nd
UWIZM 2010.12.108b zweifeli j 136 45 17 17 15 134 75
AMNH 29317 zweifeli m 365 152 17 17 15 145 79
AMNH 29332 zweifeli m 297 114 17 17 15 151 76
AMNH R-29317 zweifeli m 369 148 17 17 15 143 82
AMNH 29332 zweifeli m 322 115 17 17 15 142 74
AMNH 67877 zweifeli m 361 148 17 17 15 149 82
FMNH 17834 zweifeli m 384 101+ 17 15 15 141 nd
FMNH 217226 zweifeli m 340 139 17 17 15 138 77
FMNH 219615 zweifeli m d nd 17 17 15 142 nd
FMNH 49957 zweifeli m 398 174 17 15 15 145 79
FMNH 49958 zweifeli m 456 nd 17 17 15 145 nd
FMNH 215827 zweifeli m 354 155 17 16 15 140 78
FMNH 217227 zweifeli m 367 157 17 15 15 141 nd
FMNH 120986 zweifeli m 386 143 17 17 15 142 83
FMNH 215827 zweifeli m 354 155 17 16 15 140 78
FMNH 217227 zweifeli m 367 157 17 15 15 141 nd
UMMZ 124233 zweifeli m 394 163 17 17 15 142 83
UMMZ 124225 zweifeli m 363 149 17 17 15 144 80
UMMZ 124228 zweifeli m 415 135+ 17 17 15 143 nd
USNM 17758 zweifeli m 349 nd 17 17 15 142 nd
USNM 252682 zweifeli m 370 160 17 17 15 141 83
USNM 286922 zweifeli m 165 55 17 17 15 149 80
USNM 196332 zweifeli m 430 170 17 17 15 145 78
USNM 217198 zweifeli m 509 203 17 17 15 140 75
USNM 252682 zweifeli m 370 160 17 17 15 141 83
USNM 286922 zweifeli m 165 55 17 17 15 149 80
AMNH 98260 zweifeli nd 492 nd 17 16 15 144 nd
UWIZM 2010.12.108a zweifeli nd 360 nd 17 17 15 146 nd
UWIZM 2010.12.110 zweifeli nd 373 157 17 15 15 138 80

Appendix 3

(A) compares the single factor ANOVA results for ventral counts and (B) compares the single factor ANOVA results for subcaudal counts. Statistically significant results that resulted in the rejection of the null hypothesis are in bold.

A. ventrals
zweifeli pseudoreginae
p = 0.003
zweifeli df = 53
p = 0.00 p = 0.00
reginae df = 59 df = 15
B. subcaudals
zweifeli pseudoreginae
p = 0.350
zweifeli df = 7
p = 0.004 p = 0.230
reginae df = 38 df = 36

Appendix 4

Material used for molecular analysis and GenBank numbers. Key: * sequenced in this study.

Species Museum voucher Locality 12S 16S c-mos
Erythrolamprus aesculapii ROM 47474 Guyana - KY986512 KY986488
IBSP 74046 Brazil GQ457795 GQ457736 GQ457856
MNHN 1996.7896 French Guiana AF158462 AF158531 GQ895814
Erythrolamprus almadensis LSUMZ H-6558 Unknown KY986517 KY986497
MCP < BRA > 6528 ? JQ598808 JQ598871 JQ598979
Erythrolamprus atraventer IBSP 74342 ? JQ598809 JQ598872 JQ598980
Erythrolamprus bizona LSUMZ H-6360 Costa Rica KY986513 KY986493
Erythrolamprus breviceps MNHN 1996.7879 French Guiana AF158464 AF158533
Erythrolamprus ceii FML 14973 ? JQ598810 JQ598873 JQ598981
Erythrolamprus cobella ROM 28372 Guyana KY986514 KY986489
Erythrolamprus cursor MNHN 1887.0120 Martinique JX905307 JX905311
Erythrolamprus epinephalus LSUMZ H-1547 Peru KY986515 KY986487
None Costa Rica GU018158 GU018176
Erythrolamprus jaegeri IBSP 59252 ? GQ457809 GQ457749 GQ457869
Erythrolamprus juliae SBH 194227 Dominica AF158445 AF158514
Erythrolamprus melanotus RML 0266 Tobago KY986510 KY986492
Erythrolamprus miliaris ROM 22837 Guyana KY986511 KY986494
MZUSP 14137 ? JQ598811 JQ598874 JQ598982
None French Guiana AF158409 AF158480
Erythrolamprus mimus LSUMZ H-6398 Honduras KY986508 KY986496
ICP 1105 Costa Rica GU018157 GU018175
Erythrolamprus ocellatus CAS 245326 Tobago KY986518 KY986490
Erythrolamprus poecilogyrus LSUMZ H-6972 Argentina KY986516 KY986491
FML 15916 ? JQ598812 JQ598875
Erythrolamprus reginae IBSP 72733 ? JQ598813 JQ598876 JQ598983
MNHN 1996.7846 French Guiana AF158433 AF158501
Erythrolamprus typhlus LSUMZ H-17725 Brazil KY986509 KY986495
IBSP 70643 ? GQ457811 GQ457751 GQ457871
None French Guiana AF158410 AF158481
Xenodon histricus MZUSP 13265 ? GQ457753 GQ457873
Erythrolamprus pseudoreginae* UWIZM.2016.22.45 Tobago MK287470 MK287477 MK287484
Erythrolamprus melanotus* UWIZM.2011.19.14 Tobago MK287471 MK287481
UWIZM.2011.25 Trinidad MK287472 MK287478 MK287485
UWIZM.2016.22.51 Tobago MK287473 MK287479 MK287486
UWIZM.2012.27.26 Tobago MK287474 MK287480 MK287487
Erythrolamprus zweifeli* CAS245114 Trinidad MK287475 MK287482 MK287488
UWIZM.2014.14 Trinidad MK287476 MK287483 MK287489

Appendix 5

Table of p-uncorrected distances computed in MEGA7 (under a complete deletion option) of all species shown in Figure 2. The order of specimens from top to bottom follows Figure 2. Erythrolamprus pseudoreginae is marked in bold type and the genetic distance of its closest species (E. epinephalus) as recovered from the phylogenetic tree is shown in bold type and marker with a square.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37
1 Xenodon histricus
2 E. poecilogyrus (Argentina) 0.053
3 E. ceii (FML 14973) 0.059 0.006
4 E. poecilogyrus (FML 15916) 0.059 0.006 0
5 E. miliaris (French Guiana) 0.059 0.021 0.026 0.026
6 E. miliaris (MZUP 14137) 0.056 0.023 0.029 0.029 0.032
7 E. miliaris (Guiana) 0.056 0.023 0.029 0.029 0.032 0
8 E. typhlus (Brazil) 0.041 0.026 0.032 0.032 0.029 0.026 0.026
9 E. reginae (IBSP 72733) 0.044 0.023 0.029 0.029 0.029 0.023 0.023 0.018
10 E. reginae (French Guiana) 0.053 0.026 0.032 0.032 0.023 0.035 0.035 0.023 0.021
11 E. zweifeli (CAS245114 Trinidad) 0.053 0.032 0.038 0.038 0.035 0.041 0.041 0.029 0.032 0.026
12 E. zweifeli (2014.14 Trinidad) 0.053 0.032 0.038 0.038 0.035 0.041 0.041 0.029 0.032 0.026 0
13 E. breviceps (French Guiana) 0.053 0.009 0.015 0.015 0.018 0.026 0.026 0.023 0.023 0.029 0.029 0.029
14 E. epinephalus (Peru) 0.053 0.009 0.015 0.015 0.012 0.021 0.021 0.018 0.018 0.023 0.029 0.029 0.006
15 E. epinephalus (Costa Rica) 0.085 0.053 0.059 0.059 0.059 0.062 0.062 0.053 0.059 0.07 0.07 0.07 0.05 0.047
16 E. pseudoreginae (2016.22.45 Tobago) 0.067 0.023 0.029 0.029 0.026 0.035 0.035 0.032 0.032 0.038 0.041 0.041 0.021 0.015 0.047
17 E. melanotus (2016.22.51 Tobago) 0.056 0.023 0.023 0.023 0.032 0.029 0.029 0.032 0.029 0.041 0.038 0.038 0.021 0.021 0.047 0.029
18 E. melanotus (2012.27.26 Tobago) 0.056 0.023 0.023 0.023 0.032 0.029 0.029 0.032 0.029 0.041 0.038 0.038 0.021 0.021 0.047 0.029 0
19 E. melanotus (2011.19.14 Tobago) 0.056 0.023 0.023 0.023 0.032 0.029 0.029 0.032 0.029 0.041 0.038 0.038 0.021 0.021 0.047 0.029 0 0
20 E. melanotus (2011.25 Trinidad) 0.056 0.023 0.023 0.023 0.032 0.029 0.029 0.032 0.029 0.041 0.038 0.038 0.021 0.021 0.047 0.029 0 0 0
21 E. melanotus (Tobago) 0.056 0.023 0.023 0.023 0.032 0.029 0.029 0.032 0.029 0.041 0.038 0.038 0.021 0.021 0.047 0.029 0 0 0 0
22 E. atraventer (IBSP 74342) 0.065 0.021 0.026 0.026 0.032 0.035 0.035 0.044 0.038 0.041 0.038 0.038 0.021 0.026 0.07 0.041 0.041 0.041 0.041 0.041 0.041
23 E. jaegeri (IBSP 59252) 0.076 0.029 0.035 0.035 0.032 0.032 0.032 0.044 0.038 0.038 0.044 0.044 0.026 0.026 0.067 0.035 0.044 0.044 0.044 0.044 0.044 0.029
24 E. almadensis (MCP<BRA>6528) 0.067 0.023 0.029 0.029 0.026 0.029 0.029 0.032 0.038 0.038 0.044 0.044 0.026 0.021 0.05 0.026 0.041 0.041 0.041 0.041 0.041 0.029 0.023
25 E. almadensis (LSUMP H–6558) 0.056 0.023 0.029 0.029 0.026 0.029 0.029 0.026 0.032 0.038 0.044 0.044 0.026 0.021 0.05 0.029 0.035 0.035 0.035 0.035 0.035 0.035 0.029 0.018
26 E. juliae (Dominica) 0.065 0.021 0.026 0.026 0.023 0.026 0.026 0.029 0.029 0.035 0.041 0.041 0.018 0.012 0.047 0.021 0.026 0.026 0.026 0.026 0.026 0.026 0.026 0.021 0.026
27 E. cursor (Martinique) 0.059 0.015 0.021 0.021 0.023 0.032 0.032 0.029 0.029 0.035 0.035 0.035 0.012 0.012 0.05 0.026 0.021 0.021 0.021 0.021 0.021 0.026 0.038 0.032 0.032 0.012
28 E. typhlus (IBSN7070643) 0.079 0.044 0.044 0.044 0.047 0.056 0.056 0.053 0.059 0.059 0.053 0.053 0.041 0.041 0.056 0.044 0.041 0.041 0.041 0.041 0.041 0.044 0.05 0.038 0.044 0.035 0.038
29 E. typhlus (French Guiana) 0.076 0.035 0.035 0.035 0.038 0.047 0.047 0.044 0.05 0.05 0.05 0.05 0.032 0.032 0.053 0.041 0.035 0.035 0.035 0.035 0.035 0.047 0.047 0.041 0.047 0.026 0.032 0.032
30 E. cobella (Guyana) 0.059 0.015 0.021 0.021 0.023 0.032 0.032 0.029 0.029 0.035 0.029 0.029 0.006 0.012 0.047 0.023 0.023 0.023 0.023 0.023 0.023 0.026 0.032 0.032 0.032 0.023 0.018 0.041 0.032
31 E. aesculapii (Brazil) 0.062 0.032 0.038 0.038 0.041 0.044 0.044 0.041 0.047 0.041 0.041 0.041 0.029 0.035 0.07 0.038 0.05 0.05 0.05 0.05 0.05 0.038 0.038 0.035 0.038 0.041 0.041 0.059 0.05 0.035
32 E. ocellatus (Tobago) 0.056 0.026 0.032 0.032 0.041 0.032 0.032 0.035 0.041 0.041 0.041 0.041 0.029 0.029 0.065 0.032 0.044 0.044 0.044 0.044 0.044 0.038 0.038 0.029 0.038 0.029 0.035 0.053 0.038 0.035 0.012
33 E. aesculapii (French Guiana) 0.065 0.032 0.035 0.035 0.041 0.038 0.038 0.041 0.041 0.047 0.053 0.053 0.029 0.029 0.073 0.038 0.05 0.05 0.05 0.05 0.05 0.044 0.044 0.041 0.044 0.041 0.041 0.07 0.056 0.035 0.023 0.023
34 E. aesculapii (Guyana) 0.062 0.029 0.032 0.032 0.038 0.035 0.035 0.038 0.038 0.044 0.05 0.05 0.026 0.026 0.07 0.035 0.047 0.047 0.047 0.047 0.047 0.041 0.041 0.038 0.041 0.038 0.038 0.067 0.053 0.032 0.021 0.021 0.003
35 E. bizona (Costa Rica) 0.059 0.018 0.023 0.023 0.032 0.035 0.035 0.032 0.038 0.038 0.038 0.038 0.015 0.021 0.065 0.035 0.035 0.035 0.035 0.035 0.035 0.029 0.035 0.035 0.035 0.032 0.026 0.056 0.041 0.021 0.021 0.021 0.026 0.023
36 E. mimus (Costa Rica) 0.059 0.018 0.023 0.023 0.032 0.035 0.035 0.032 0.038 0.038 0.038 0.038 0.015 0.021 0.065 0.035 0.035 0.035 0.035 0.035 0.035 0.029 0.035 0.035 0.035 0.032 0.026 0.056 0.041 0.021 0.021 0.021 0.026 0.023 0.006
37 E. mimus (Honduras) 0.059 0.018 0.023 0.023 0.032 0.035 0.035 0.032 0.038 0.038 0.038 0.038 0.015 0.021 0.065 0.035 0.035 0.035 0.035 0.035 0.035 0.029 0.035 0.035 0.035 0.032 0.026 0.056 0.041 0.021 0.021 0.021 0.026 0.023 0.006 0