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Research Article
Systematics of Nothopsini (Serpentes, Dipsadidae), with a new species of Synophis from the Pacific Andean slopes of southwestern Ecuador
expand article infoRobert Alexander Pyron, Juan Manuel Guayasamin§, Nicolas Peñafiel|, Lucas Bustamante, Alejandro Arteaga
‡ The George Washington University, Washington, United States of America
§ Universidad Tecnológica Indoamérica, Quito, Ecuador
| MZUTI, Quito, Ecuador
¶ Tropical Herping, Quito, Ecuador
Open Access

Abstract

Within Dipsadinae, some recent authors have recognized a tribe Nothopsini containing the genera Diaphorolepis, Emmochliophis, Nothopsis, Synophis, and Xenopholis, on the basis of a number of putative morphological synapomorphies. However, molecular results suggest that Nothopsis, Synophis, and Xenopholis do not form a monophyletic group, while the remaining taxa are unsampled in recent molecular phylogenies. Here, DNA-sequence data for some Diaphorolepis and Synophis species are provided for the first time, as well as additional new sequences for Nothopsis and some Synophis species. Including these and other existing data for nothopsine species, previous studies showing that Nothopsini is not a natural group are corroborated. Nothopsini Cope, 1871 is restricted to Nothopsis. Diaphorolepidini Jenner, 1981 is resurrected and re-delimited to include only Diaphorolepis, Emmochliophis, and Synophis. Finally, Xenopholis remains Dipsadinae incertae sedis. Known material of Diaphorolepidini is reviewed to generate revised and expanded descriptions and diagnoses at the tribe, genus, and species level. Numerous cryptic species are likely present in S. bicolor and S. lasallei. Finally, a new population from the low-elevation cloud forests of SW Ecuador is reported upon, which is genetically and morphologically distinct from all other species, that is here named Synophis zaheri sp. n.

Keywords

Serpentes, Dipsadinae, Nothopsini, Diaphorolepis, Synophis

Introduction

Within Dipsadinae (sensu Pyron et al. 2013), Diaphorolepis, Emmochliophis, Nothopsis, Synophis, and Xenopholis were historically thought to form a monophyletic group on the basis of scutellation, osteological, histological, hemipenial, and respiratory characters (see Sheil and Grant 2001). The group has been referred to as tribe Nothopsini by some authors (Savitzky 1974; Dowling and Duellman 1978). The genera Amastridium, Chersodromus, and Ninia have also been referred to this assemblage (Wallach 1995). Alternatively, Jenner (1981) proposed a tribe Diaphorolepidini containing Diaphorolepis along with Atractus, Chersodromus, Crisantophis, Elapomorphus, Enulius, Gomesophis, Pseudotomodon, Ptychophis, and Sordellina, while Synophis was placed in Philodryadini, and Emmochliophis was not accounted for.

Most subsequent studies have considered Nothopsini to contain only Diaphorolepis, Emmochliophis, Nothopsis, Synophis, and Xenopholis (see Sheil and Grant 2001; Martinez 2011). Some of these taxa, Nothopsis in particular, bear a strong external resemblance to Asian xenodermatids such as Xenodermus (Bogert 1964). In contrast, molecular phylogenetic analyses have strongly supported Nothopsis (Vidal et al. 2010), Synophis (Sheehy 2012), and Xenopholis (Vidal et al. 2010; Pyron et al. 2011; Grazziotin et al. 2012) as dipsadines, as does hemipenial morphology (Zaher 1999). However, these genera do not form a monophyletic group within Dipsadinae in molecular phylogenies, and are widely separated in different dipsadine clades (Vidal et al. 2010; Grazziotin et al. 2012; Sheehy 2012; Pyron et al. 2013).

Thus, the tribe Nothopsini does not appear to represent a natural group, despite the putative morphological synapomorphies uniting the taxa listed above (Savitzky 1974; Ferrarezzi 1994; Wallach 1995; Martinez 2011). Contrastingly, the strength of the molecular results suggests that these likely represent convergence, at least between Nothopsis and Xenopholis. This is not surprising, given the massive ecomorphological diversification exhibited by Dipsadinae following their adaptive radiation in the Neotropics (Cadle 1984a, b, c).

However, Diaphorolepis and Emmochliophis have still not been sampled in any molecular phylogeny, and it is thus unclear where their phylogenetic affinities lie. Morphological evidence suggests that these two genera form a clade with Synophis (see Hillis 1990). Furthermore, there are multiple species of Synophis, with potentially unclear species boundaries (Bogert 1964; Fritts and Smith 1969; Sheil 1998; Sheil and Grant 2001). Here, we report on new material from Diaphorolepis, Synophis, and Nothopsis, present a new molecular phylogeny, and describe a new species of Synophis. We review current knowledge of Diaphorolepis, Emmochliophis, and Synophis, and discuss species limits in these genera. Dipsadine diversity in the Andes is clearly underestimated, and new species are still being discovered in the 21st century (e.g., Salazar-Venezuela et al. 2014; Sheehy et al. 2014; Zaher et al. 2014).

Materials

Molecular phylogeny

Work in Ecuador was carried out under permit number MAE-DNB-CM-2015-0017. We obtained tissue samples of Diaphorolepis wagneri (3 specimens), Synophis bicolor (3), S. calamitus (1), S. lasallei (1), a new Synophis species (2), and Nothopsis rugosus (1), via fieldwork in Ecuador. The specimens are deposited at the Museo de Zoología at the Universidad Tecnológica Indoamérica (MZUTI; Tables 1, 2). We also obtained a tissue loan of the holotype of S. calamitus from Ecuador (KU 197107; Hillis 1990) from the University of Texas at Austin.

Morphometric data for specimens of Diaphorolepidini species examined or from literature. Codes are: MT=maxillary teeth; IL=infralabials; SL=supralabials; PO=postoculars; V=ventrals; SC=subcaudals; D1-3=dorsal scale rows at neck, midbody, and vent; SVL=snout-vent length (mm); TL=tail length (mm). Museum codes are given in Sabaj-Perez (2013). Includes data from ReptiliaWebEcuador (Torres-Carvajal et al. 2014).

Species Collection MT IL SL PO V SC D1 D2 D3 SVL TL Sex
Diaphorolepis laevis NMW 14860 16 10 8/9 2 157 84 19 19 17 350 145 -
Diaphorolepis wagneri AMNH 49179 23 10 8 3 194 138 21 19 17 290 153 M
Diaphorolepis wagneri GML 4-00014 25 10 9 2 197 133 21 19 17 355 187 F
Diaphorolepis wagneri KU 75682 24 10 9 2 196 136 21 19 17 311 142 F
Diaphorolepis wagneri MECN 2937 - - 9 3 181 133 19 19 17 276 129 M
Diaphorolepis wagneri MZUTI 3322 - 11 8 2 189 141 19 19 17 332 167 F
Diaphorolepis wagneri MZUTI 3752 - 11 8 1 189 134 21 19 17 447 257 M
Diaphorolepis wagneri MZUTI 3901 - 13 9 3 195 131 19 19 17 524 259 F
Diaphorolepis wagneri NMW 18915 - 13 9 2 191 137 21 19 17 307 146 M
Diaphorolepis wagneri ZSM 2708/0 25 12 9 2 193 98 21 19 17 484 200 F
Emmochliophis fugleri UIMNH 78795 16 8 8 2 140 97 19 19 19 - - M
Emmochliophis miops BMNH 1946.1.12.30 13 8 8 1 145 93 19 19 19 251 134 F
Eastern Andes
Synophis aff. bicolor FHGO 9186 - 11 9 2 164 105 19 17 17 379 184 M
Synophis aff. bicolor MZUTI 3529 - 11 8 2 163 106 19 19 17 407 202 M
Synophis aff. bicolor MZUTI 4180 - 11 9 2 152 100 19 19 18 457 214 M
Synophis aff. bicolor UMMZ 91550 24/27 11 9 2 160 103 - 19 17 529 235 F
Synophis aff. bicolor UMMZ 91551 - - 8 2 161 105 - 19 17 535 230 F
Synophis aff. bicolor UMMZ 91552 - - 8 2 166 106 - 19 17 153 61 F
Western Andes
Synophis aff. bicolor BMNH 1940.2.30.31 - - 8 2 162 118 21 19 17 408 241 M
Synophis aff. bicolor CAS 23612 - - 8 2 166 100 - 19 17 186 80 F
Synophis aff. bicolor MCZ R-164530 - 11 9 2 164 116 - 19 17 367 208 -
Synophis aff. bicolor QCAZ 10453 - 11 8 2 - - - - - - - -
Synophis aff. bicolor TCWC 66209 - 11 8 2 160 96 21 19 17 - - -
Synophis aff. bicolor UMMZ 185812 - 10 8 2 165 105 - 19 17 144 66 -
Synophis aff. bicolor UMMZ 185813 - 10 8 2 162 122 - - - 257 147 -
Synophis cf. bicolor MHUA 14133 >23 12 8 2 193 127 - 19 - - - M
Synophis cf. bicolor MHUA 14577 24 11 8 2 190 131 19 19 17 - - -
Synophis cf. bicolor MLS2072 - 11/10 8 2 184 127 - 19 17 407 210 M
Synophis bicolor MECN 6732 - 9 8 2 174 138 19 17 17 361 236 M
Synophis bicolor MECN 6733 - 9 8 2 174 132 19 19 17 406 245 M
Synophis bicolor MECN 8076 - 9 8 2 183 135 19 17 17 376 233 M
Synophis bicolor MZUT 257 16 9 8 2 180 136 - 19 17 - - -
Synophis bicolor MZUTI 4175 - 11 8 2 174 143 19 19 17 365 245 M
Synophis bicolor UTA R-55956 - 9 8 2 176 129 - 19 17 - - -
Synophis calamitus KU 164208 - 9 8 1 163 125 21 19 17 142 73 -
Synophis calamitus KU 197107 - 9 7 1 166 110 21 19 17 149 74 F
Synophis calamitus MZUTI 3694 - 11 9 2 166 118 23 19 17 462 265 M
Synophis calamitus QCAZ 11931 - 9 8 1 - - - - - - - -
Synophis lasallei FMNH 81313 24 - - 2 154 112 - 21 - 292 158 F
Synophis lasallei EPN S.974 - - - 2 156 116 - 21 - 175 90 M
Synophis lasallei EPN S.975 24 - - 2 155 119 - 21 - 354 201 M
Synophis lasallei FHGO 6489 - 11 8 2 147 111 23 21 21 153 86 M
Synophis lasallei FHGO 8340 - 11 8 2 153 88 21 19 17 415 199 M
Synophis lasallei MCZ R-156873 - 11 7 1 147 115 - - - 412 206 -
Synophis lasallei MECN 11250 - 10 8 2 153 98 21 19 17 412 196 F
Synophis lasallei MECN 11262 - - 8 2 154 118 21 21 17 306 145 M
Synophis lasallei MECN 2220 - 10 8 2 165 117 19 19 17 294 146 M
Synophis lasallei MLS/CJSP - - - 2 144 101 - - - 300 170 M
Synophis lasallei MZUTI 4181 - 11 9 2 156 29 21 21 19 272 42 M
Synophis lasallei USNM 233061 - 11 9 2 156 124 - 21 - 285 160 M
Synophis lasallei USNM 233062 - 11 8 2 153 126 - 22 20 360 200 -
Synophis lasallei USNM 233063 - 11 8 2 151 86 23 21 19 308 197 M
Synophis lasallei USNM 233064 - 11 8 2 151 - - 21 19 270 150 -
Synophis plectovertebralis UVC 11580 - 8 8 1 144 91 19 19 17 212 100 M
Synophis plectovertebralis UVC 11858 - 7 7 1 147 79 19 19 17 196 76.5 F
Synophis zaheri MZUTI 3353 - 8 8 2 166 112 19 19 17 351 184 M
Synophis zaheri MZUTI 3355 - 9 8 2 169 111 19 19 17 372 194 M

We isolated total DNA from liver tissue or tail tips by proteinase K digestion in lysis buffer, followed by protein precipitation with guanidine thiocyanate solution and final DNA precipitation using isopropyl alcohol. We used the following pairs of primers to amplify and sequence four mitochondrial genes (12S, 16S, CYTB, ND4) and one nuclear locus (CMOS): Snake_12S_F (5’-AAACTGGGATTAGATACCCCACTAT-3’), Snake_12S_R (5’-GTRCGCTTACCWTGTTACGACT-3’), Snake_16S_F (5’-CGCCTGTTTAYCAAAAACAT-3’), and Snake_16S_R (5’-CCGGTCTGAACTCAGATCACGT-3’) from Kessing et al. (1989); Snake_Cytb_F (5’-GACCTGTGATMTGAAAACCAYCGTTGT-3’) and Snake_Cytb_R (5’-CTTTGGTTTACAAGAACAATGCTTTA-3’) from Burbrink et al. (2000); Snake_ND4_F (5’-CACCTATGACTACCAAAAGCTCATGTAGAAGC-3’) and Snake_ND4_R (5’-CATTACTTTTACTTGGATTTGCACCA-3’) from Arévalo et al. (1994); and Snake_cmosFs77 (5’-CATGGACTGGGATCAGTTATG-3’) and Snake_cmosRs78 (5’-CCTTGGGTGTGATTTTCTCACCT-3’) from Lawson et al. (2005).

We set up PCR reactions to a total volume of 25 µL containing MgCl2 2–3 mM, dNTPs 200 µM, 0.2 µM of each primer (0.8 µM in the case of ND4) and 1.25 U (16S and Cytb) or 0.625 U (ND4 and c-mos) of Taq DNA polymerase (Invitrogen). Thermocycling parameters consisted of an initial three-minute step at 94 °C; 25 to 30 cycles of 45–60 sec at 94 °C, 45 (16S and c-mos) or 60 (ND4 and Cytb) sec at 53–60 °C, 1 (16S and c-mos) or 2 (ND4 and Cytb) min at 72 °C; and a final extension of 7 min at 72 °C. We used 1.5% agarose gels to visualize the PCR products and QIAquick PCR purification Kit (QIAGEN) to remove unincorporated primers and dNTPs from every PCR reaction before they were sent to Macrogen Inc. for sequencing.

We combined these new data with the publically available sequences for Nothopsis and Xenopholis (Vidal et al. 2010; Grazziotin et al. 2012). We obtained additional sequences of S. bicolor from the Museu de Zoologia da Universidade de São Paulo (MHUA 14577 [Museo de Herpetología de la Universidad de Antioquia], from Colombia: 12S, 16S, CYTB, and CMOS) and the University of Texas, Arlington (UTA-R 55956 from Ecuador: CYTB and ND4).

We then included all publically available dipsadine species sampled for these genes. This matrix contains 24% missing data (‘-’), but these have been shown not to have deleterious effects on taxon placement and support in previous analyses (e.g., Pyron et al. 2011). Data were aligned using MAFFT (Katoh and Standley 2013) under the default parameters in Geneious 7.1.9 (Biomatters Ltd.). We determined the optimal partitioning strategy using PartitionFinder (Lanfear et al. 2012). We estimated the phylogeny using MrBayes 3.2.5 (Ronquist et al. 2012), with 4 runs of 4 chains each, run for 20 million generations with the first 25% discarded as burnin. Convergence was assumed as the average standard deviation of split frequencies went to zero and the potential scale reduction factors went to one (Ronquist et al. 2012). The GenBank accession numbers for the new and existing data are given in Appendix I.

Morphological data

Species in Diaphorolepis, Emmochliophis, and Synophis have traditionally been delimited using easily determined external morphological characters (Bogert 1964; Hillis 1990). We relied here on a set of these characters, scored for museum specimens and our new material, to examine and delimit species boundaries (Table 1). For available specimens examined in person, in photographs, or in the literature, we recorded SVL and TL in mm, and counts of supralabials, infralabials, postoculars, ventrals, and subcaudals. We made cursory notes on the hemipenes of some male specimens when they were visible (Zaher 1999; Martinez 2011).

Results

Molecular phylogeny

The overall topology and support (Figs 1, 2) is similar to numerous recent studies (Zaher et al. 2009; Vidal et al. 2010; Pyron et al. 2011; Grazziotin et al. 2012). We consider strong support to be posterior probabilities ≥95%, following recent authors (Felsenstein 2004). Overall, there is low support for many backbone nodes, which may reflect inadequate sampling of taxa (only ~250 out of ~900 dipsadine species) or characters (only two independent loci).

Figure 1.

Phylogeny (part) of ~245 dipsadine species plus outgroups, based on partitioned, multi-gene Bayesian inference analysis of 3,462bp of mitochondrial and nuclear DNA. Support values given are posterior probabilities ≥50% from 15 million post-burnin generations.

Figure 2.

Phylogeny (part) of ~245 dipsadine species plus outgroups, based on partitioned, multi-gene Bayesian inference analysis of 3,462bp of mitochondrial and nuclear DNA. Support values given are posterior probabilities ≥50% from 15 million post-burnin generations.

Species in Dipsadinae can be broadly grouped into a primarily North American clade (Contia to Carphophis when viewing Fig. 1), a primarily Central American clade (Diaphorolepis to Atractus in Fig. 1), and a primarily South American clade (Crisantophis to Apostolepis in Fig. 2), though many species in the latter two clades range across both Central and South America. Several speciose genera in the primarily Central American clade are non-monophyletic, including Imantodes, Hypsiglena, Geophis, Sibon, Dipsas, Sibynomorphus (Fig. 1), as in previous studies (Grazziotin et al. 2012; Pyron et al. 2013).

In agreement with previous results (Grazziotin et al. 2012; Pyron et al. 2013), we find that Nothopsini is not a natural group (Fig. 1). The genus Nothopsis is strongly supported, and strongly placed with Leptodeira + Imantodes within the Central American clade. Correspondingly, Xenopholis is strongly supported and weakly nested within the South American clade, as the sister lineage to Hydrodynastes. It appears that one Xenopholis scalaris (KU 222204) from a previous study (Pyron et al. 2011) may have been misidentified, and is actually related to X. undulatus. This specimen is strongly supported as the sister lineage to the sampled X. undulatus (R-6955), to the exclusion of the three other sampled X. scalaris, which are strongly supported as a monophyletic group. This specimen is from the Peruvian Amazon and is pictured in Duellman and Mendelson (1995). The specimen pictured resembles the Amazonian X. scalaris, rather than the more xeric X. undulatus from the Brazilian shield. Thus, it is possible either that a curatorial or laboratory error occurred at some point, or that there is cryptic genetic diversity in Xenopholis.

A strongly-supported clade comprising Diaphorolepis and Synophis represents the sister to the large, primarily Central American clade that also contains Nothopsis. Monophyly of Synophis with respect to Diaphorolepis is weakly supported. Within a weakly paraphyletic S. bicolor, there are three deeply divergent lineages, and the sampled specimen of S. lasallei. An apparently new species of Synophis is the strongly-supported sister lineage of S. calamitus. The species S. plectovertebralis remains unsampled in the molecular phylogeny. Although Emmochliophis is not sampled, we follow previous authors in assuming a close relationship with Diaphorolepis and Synophis, given their strong resemblance (Savitzky 1974; Hillis 1990). Thus, the synapomorphies previously used to diagnose Nothopsini (Savitzky 1974; Wallach 1995) apparently represent convergence in at least three distantly related dipsadine lineages.

Systematics

We seek here to only name clades associated Nothopsini that are strongly supported in our molecular phylogeny. Above the genus level, Nothopsini is not a natural group in any of its recent conformations. We place Nothopsis alone in Nothopsini Cope, 1871. We resurrect and re-delimit the tribe Diaphorolepidini Jenner, 1981 to include only Diaphorolepis, Emmochliophis, and Synophis. The genus Xenopholis is not strongly supported in any supra-generic group and remains incertae sedis in Dipsadinae (see Grazziotin et al. 2012).

Our molecular and morphological data (Tables 13; Figs 1, 2) also corroborate previous authors in finding that genus and species boundaries within Diaphorolepidini are unclear and in need of revision (Sheil and Grant 2001). We here provide photographs and range maps of representative material (Figs 39). A number of issues are immediately apparent, and can be addressed with our results. We outline these below.

Figure 3.

Photographs of some diaphorolepidine species in life: a Synophis zaheri MZUTI 3353 b S. zaheri MZUTI 3355 c S. calamitus MZUTI 3694 d S. aff. bicolor MZUTI 3529 e S. lasallei uncat., and f Diaphorolepis wagneri MZUTI 3901.

Figure 4.

Photographs of some diaphorolepidine species in life: Synophis bicolor UTA R-55956 (a), and S. cf. bicolor MHUA 14577 (b).

Figure 5.

Map of vouchered localities for Synophis lasallei (yellow circles), S. plectovertebralis (pink circles), S. calamitus (teal circles), S. zaheri (red circles), Emmochliophis miops (green triangle) and E. fugleri (blue triangle).

Figure 6.

Map of vouchered localities for Diaphorolepis wagneri (teal squares).

Figure 7.

Map of vouchered localities for Synophis bicolor populations: S. bicolor sensu stricto (purple circles), western S. aff. bicolor (blue circles), eastern S. aff. bicolor (yellow circles), and S. cf. bicolor (teal circles).

Figure 8.

Photographs in preservation of some diaphorolepidine species. Upper: Diaphorolepis wagneri MZUTI 3901, Center: Synophis zaheri MZUTI 3355, Lower: S. calamitus MZUTI 3694.

Figure 9.

Photographs in preservation of some diaphorolepidine species. Upper: Synophis bicolor MZUTI 4175, Middle: S. lasallei MZUTI 4181, Lower: S. aff. bicolor MZUTI 4180.

Vouchered localities for specimens of Diaphorolepidini species examined or from literature. In general, localities are given verbatim as transcribed from the literature, museum records, or field notes. Co-ordinates represent georeferencing attempts from gazetteers under standard guidelines, though some variation from the exact collecting locality will inevitably be present. Similarly, elevations are taken from Google Earth, and may not exactly match the elevations as originally reported. Museum codes are given in Sabaj-Perez (2013). Includes data from ReptiliaWebEcuador (Torres-Carvajal et al. 2014).

Species Collection Number Locality Latitude Longitude Elev.
Diaphorolepis wagneri GML 4-00014 Panama Darien, Cerro Mali, in Serrania del Darien 8.128557 -77.253498 1268
Diaphorolepis wagneri MECN 2937 Canandé, Ecuador 0.529930 -79.035410 596
Diaphorolepis wagneri MZUTI 3322 Milpe, Ecuador 0.034890 -78.867130 1076
Diaphorolepis wagneri MZUTI 3901 Mashpi Lodge, Ecuador 0.164030 -78.870730 1068
Diaphorolepis wagneri NMW 18915 El Palmar, Canar, Ecuador -2.533300 -79.333300 325
Diaphorolepis wagneri QCAZ 380 Ecuador, Cotopaxi, Las Pampas -0.348360 -79.076010 1238
Diaphorolepis wagneri QCAZ 381 Ecuador, Pichincha, Tandapi -0.415220 -78.797280 1457
Diaphorolepis wagneri QCAZ 8450 Ecuador, Cotopaxi, Pucayacu–Sigchos -0.702730 -79.056810 974
Diaphorolepis wagneri QCAZ 8782 Imbabura Lita, Ecuador 0.815270 -78.388350 865
Diaphorolepis wagneri UVC 12187 18km East of San Jose de Palmar, Colombia 4.966667 -76.233333 1546
Diaphorolepis wagneri UVC 5254 Colombia, Cali, Pichinde, Farallones de Cali 3.433400 -76.616680 1614
Diaphorolepis wagneri UVC 5255 Colombia, Pance, Camino a Corea, Pance, Farallones de Cali 3.328340 -76.638650 1632
Emmochliophis fugleri UIMNH 78795 4 km. E Río Baba Bridge, 24 km. S Santo Domingo de los Colorados, Pichincha, Ecuador -0.435562 -79.246212 618
Emmochliophis miops BMNH 1946.1.12.30 Parambas (Imbabura), Ecuador 0.805000 -78.350833 1105
Eastern Andes
Synophis aff. bicolor FHGO 9186 Río Zopladora, Ecuador -2.611510 -78.472174 1677
Synophis aff. bicolor KU 121341 Ecuador, Pastaza, Mera -1.457452 -78.107976 1111
Synophis aff. bicolor MZUTI 3529 Wild Sumaco, Ecuador -0.675700 -77.601290 1463
Synophis aff. bicolor MZUTI 4180 El Genairo, Ecuador -4.166181 -78.94094 1212
Synophis aff. bicolor UMMZ 91550 Ecuador, Napo-Pastaza, Abitagua -1.383000 -78.083000 1482
Western Andes
Synophis aff. bicolor BMNH 1940.2.30.31 Río Solaya, Ecuador -0.010213 -78.819510 1008
Synophis aff. bicolor CAS 23612 Chimborazo, Naranjapata, Ecuador -2.266667 -79.083333 763
Synophis aff. bicolor MCZ R-164530 Ecuador, Pichincha, Tandapi -0.419803 -78.801132 1714
Synophis aff. bicolor QCAZ 10453 Cotopaxi: Naranjito, Bosque Integral Otonga -0.417820 -78.988030 1655
Synophis aff. bicolor TCWC 66209 Ecuador, Cotopaxi, Las Pampas -0.348360 -79.076010 1238
Synophis aff. bicolor UMMZ 185812 Ecuador, Cotopaxi, San Francisco de Las Pampas -0.440357 -78.966629 1586
Synophis cf. bicolor MHUA 14577 Colombia, Dpto. Antioquia, Mpio. Amalfi, V. da La Manguita, Fca. La Esperanza 6.978611 -75.044444 1394
Synophis cf. bicolor MLS 2072 Medellin, Cordillera Central, Colombia 6.230833 -75.590556 1497
Synophis bicolor MECN 6732 Tobar Donoso, Ecuador 1.189930 -78.504130 229
Synophis bicolor MECN 6733 Sendero Awa, Ecuador 1.164400 -78.507120 257
Synophis bicolor MZUTI 4175 Itapoa, Ecuador 0.46411 -79.15547 267
Synophis bicolor UTA R-55956 Ecuador, Esmeraldas, Canton San Lorenzo 1.03212 -78.613780 318
Synophis calamitus KU 164208 9 km SE Tandayapa, Pichincha Province, Ecuador -0.047404 -78.632804 2169
Synophis calamitus KU 197107 4 km SE Tandayapa, Pichincha Province, Ecuador -0.012514 -78.650697 1889
Synophis calamitus MZUTI 3694 Tambo Tanda, Ecuador -0.020108 -78.651012 2048
Synophis lasallei EPN S.974 Ecuador, Napo-Pastaza, nr. Río Talin, headwaters of the Río Bobonaza -1.466670 -77.883300 948
Synophis lasallei FHGO 6489 Ceploa, Ecuador -1.339063 -77.670660 839
Synophis lasallei FHGO 7770 Cara del Indio, Ecuador -3.575695 -78.451020 1207
Synophis lasallei FHGO 8340 El Quimi, Ecuador -3.571852 -78.516598 752
Synophis lasallei FMNH 81313 Colombia, Meta, Pico Renjifo, Serrania de la Macarena 2.476901 -73.794852 520
Synophis lasallei KU 164221 2 km SSW Río Reventador, Ecuador -0.100000 -77.600000 1479
Synophis lasallei MCZ R-156873 Ecuador, Napo Prov., Inecel Station, Cascada San Rafael, Río Quijos -0.103401 -77.585487 1290
Synophis lasallei MECN 11250 Paquisha Alto, Ecuador -3.909518 -78.487244 1660
Synophis lasallei MECN 11262 El Pangui, Ecuador -3.624502 -78.586510 814
Synophis lasallei MECN 2220 Puyo, Ecuador -1.466780 -77.983350 957
Synophis lasallei MLS/CJSP N of Alban, cen. Cundinamarca Dept., cen. Colombia 4.883333 -74.450000 1983
Synophis lasallei MZUTI 4181 Sacha Yaku, Ecuador -1.407882 -77.711092 974
Synophis lasallei USNM 233061 Río Arajuno, headwaters of, tributary of Río Napo, Pastaza, Ecuador -1.400000 -77.883300 969
Synophis lasallei USNM 233062 Río Siquino, tributary of Río Villano, Upper Curaray, Pastaza, Ecuador -1.455303 -77.714685 576
Synophis lasallei USNM 233063 Río Bobonaza, headwaters of, Ecuador -1.512156 -77.833454 594
Synophis lasallei WWL 977-978 Colombia, Meta prov., Villavicencio 4.150000 -73.633333 539
Synophis plectovertebralis UVC 11580 Haciendo San Pedro, 6km S El Queremal, Municipio Dagua, Valle del Cauca, Colombia 3.483333 -76.700000 1830
Synophis zaheri MZUTI 3353 Buenaventura Lodge, Ecuador -3.647970 -79.755070 874
Synophis zaheri MZUTI 3355 Buenaventura Lodge, Ecuador -3.648820 -79.756400 812

Summary of measured diagnostic characters (external meristic features) for diaphorolepidine species. These data are a summary of Table 1 (omitting some subcaudal scale counts from apparently truncated tails), and can be used to identify ambiguous specimens in the field or collections, and should be updated with new material in the future.

Species MT IL SL PO V SC D1 D2 D3
Diaphorolepis laevis 16 10 8–9 2 157 84 19 19 17
Diaphorolepis wagneri 23–25 10–13 8–9 1–3 181–197 131–141 19–21 19 17
Emmochliophis fugleri 16 8 8 2 140 97 19 19 19
Emmochliophis miops 13 8 8 1 145 93 19 19 19
Synophis aff. bicolor 24–27 10–11 8–9 2 152–166 96–122 19–21 17–19 17–18
Synophis cf. bicolor 23–24 10–12 8 2 184–193 127–131 19 19 17
Synophis bicolor 16 9–11 8 2 174–183 129–143 19 17–19 17
Synophis calamitus 9–11 7–9 1–2 163–166 110–125 21–23 19 17
Synophis lasallei 24 10–11 7–9 1–2 144–165 101–126 19–23 19–22 17–21
Synophis plectovertebralis 7–8 7–8 1 144–147 79–91 19 19 17
Synophis zaheri 8–9 8 2 166–169 111–112 19 19 17

First, the head scalation of Diaphorolepis wagneri has not been accurately characterized by most authors (see Bogert 1964). Additionally, the holotype of D. laevis was incorrectly described with respect to several major characters (Werner 1923). Finally, reviewing museum specimens, including most holotypes, reveals that the current species boundaries and diagnoses are oftentimes inaccurate with respect to the observed range of variation in the relevant characters. In particular, the holotype of S. bicolor does not match many populations typically referred to this species (Bogert 1964; Hillis 1990; Sheil and Grant 2001).

In the case of Diaphorolepis wagneri, the postoculars can range from 1–3 (rather than 1–2), as illustrated by Bogert (1964), but not discussed explicitly. Werner (1901) apparently considered the small, lower postocular to be a subocular. Occasionally, the middle postocular will not be in contact with the brille, and resembles a temporal, behind the two remaining postoculars. As noted previously, the nasals are never divided, but only creased (Sheil and Grant 2001), contrary to reports from some previous authors (Bogert 1964; Hillis 1990).

In the case of Diaphorolepis laevis, Werner (1923) diagnosed the species as having fewer ventrals and subcaudals than D. wagneri, and smooth dorsal scales. Examination of the holotype (NMW 14860) reveals that it is indeed keeled, albeit weakly, throughout most of the midbody and posterior dorsal scale rows. This includes a bicarinate vertebral scale row that was previously considered to be diagnostic only of D. wagneri. The specimen appears to have a lighter-colored nuchal collar, though this may be a preservation artifact. The type locality within Colombia is unknown.

In the case of Synophis bicolor, the holotype (MZUT 257) has 180 ventrals, 136 subcaudals, and 9 infralabials, whereas sampled populations from the Andes of Ecuador typically have 152–166 ventrals, 96–122 subcaudals, and 10 or 11 infralabials. The locality of the holotype is unknown. Sampled populations from the Chocó of Ecuador match the holotype more closely, with 174–183 ventrals, 129–143 subcaudals, and 9–11 infralabials. The Chocóan populations typically occur at low to middle elevations (~200–300m), whereas Andean populations occur at higher elevations (~800–1700m). Populations from the northern western Andes of Colombia have 184–193 ventrals, 127–131 subcaudals, and 10–12 infralabials.

These three populations (Chocóan, Colombian Andean, and Ecuadorean Andean; Figs 3D, 4), correspond to three deeply divergent genetic lineages within Synophis bicolor (Fig. 1). A full revision of this species complex is pending further molecular and morphological sampling. We refer to the Chocóan populations as S. bicolor, the Ecuadorean Andean populations as S. aff. bicolor, and the Colombian Andean populations as S. cf. bicolor (using aff. versus cf. somewhat arbitrarily) for the remainder of the paper. The S. bicolor group is also weakly paraphyletic with respect to the sampled specimen of S. lasallei, which is the sister lineage of the Ecuadorean Andean lineages. The specimen of S. lasallei (MZUTI 4181) strongly matches the other S. lasallei specimens examined (Table 1), and is thus not a mis-identified S. bicolor.

Finally, we report here on two specimens of Synophis aff. calamitus from low to middle elevations on the Pacific versant of the Andes in SW Ecuador. These are diagnosable from the species above based on numerous characters, and we here name them:

Synophis zaheri sp. n.

Figs 3, 5, 8

Holotype

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

Paratype

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

Etymology

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

Diagnosis

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

Description

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

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

Diaphorolepidini Jenner, 1981

Diaphorolepis Jan, 1863 (type genus by original designation)

Emmochliophis Fritts & Smith, 1969

Synophis Peracca, 1896

Etymology

Apparently from the Greek diaphoros for “differentiated” and lepis for “scales,” likely referring to the enlarged vertebral scale row as compared to the rest of the dorsal scales.

Description

A group of relatively small-sized (<550mm SVL) dipsadine snakes restricted to the Darien of Panama and northern Andes of South America with fused prefrontals and either an expanded vertebral scale row (Diaphorolepis) or expanded zygapophyses and neural spines in adults (Emmochliophis and Synophis).

Notes

The tribe name has also been spelled ‘Diaphorolepini’ by Sheehy (2012), but Diaphorolepidini is the correct spelling based on the suffix –lepis, for which the stem is –lepid + –ini. This is a greatly restricted definition of Diaphorolepidini over the original description (Jenner 1981), which included Atractus, Chersodromus, Crisantophis, Elapomorphus, Enulius, Gomesophis, Pseudotomodon, Ptychophis, and Sordellina.

Diaphorolepis Jan, 1863

Diaphorolepis laevis Werner, 1923

Diaphorolepis wagneri Jan, 1863 (type species by monotypy)

Etymology

Apparently from the Greek diaphoros for “differentiated” and lepis for “scales,” likely referring to the enlarged vertebral scale row as compared to the rest of the dorsal scales.

Description

Relatively small-sized (<550mm SVL) dipsadine snakes restricted to the Darien in Panama and northern Andes of South America, with 16–25 maxillary teeth, 10–13 infralabials, 8 or 9 supralabials, fused prefrontals, internasals in contact, loreal present, 1–3 postoculars, 157–197 ventrals, 84–141 subcaudals, dorsal scales in (19–21)-19-17 rows, and expanded vertebral scale row with weak to strong double keeling.

Notes

This genus was validly described by Jan (1863), and re-described by Werner (1897). Werner (1901) later incorrectly deemed Jan’s name a nomen nudum, and re-described the genus and type species, designating a neotype. However, this was an error of interpretation, later realized by Werner himself (Werner 1929), and neither the re-description or neotype designation have any nomenclatural validity (see Bogert 1964). The lower subcaudal counts for some specimens likely represent truncated tails.

Diaphorolepis laevis Werner, 1923

Holotype

NMW 14860, locality given only as “Colombia.”

Etymology

Apparently from the Latin laevis for “smooth,” referring to the anterior dorsal scales.

Description

Relatively small-sized snake (350mm SVL) with 10 infralabials, 8/9 supralabials, 2 postoculars, internasals in contact, fused prefrontals, loreal present, nuchal collar apparently present, 16/18 maxillary teeth, 157 ventrals, 84 subcaudals, 19-19-17 dorsal scale rows, vertebral scale row is enlarged, with single keels on lateral dorsal scale rows and double keels on enlarged vertebral scale row weak to absent anteriorly and weak posteriorly. Uniformly light-colored venter and dark-colored dorsum in preservative. Nothing is known of the hemipenes or vertebrae.

Notes

Known only from the type specimen. The original description states that the dorsal scales are smooth, but weak keels are evident throughout the posterior portion of the body. A specimen at Harvard, reportedly from Leticia, Amazonas, Colombia, bears the identification Diaphorolepis laevis (MCZ R-143839). Upon examination, this specimen is clearly not Diaphorolepis on the basis of divided prefrontals (versus united in Diaphorolepis), lack of an enlarged bicarinate vertebral scale row (versus presence), and presence of an ocellated dorsal color-pattern (versus uniformly colored dorsum). The overall resemblance is of Dipsas sp.

Diaphorolepis wagneri Jan, 1863

Holotype

ZSM 2708/0, locality given only as “Andes of Ecuador.” We revise this by subsequent restriction (sensu Smith 1953) to Milpé, Pichincha province, Ecuador (0.035, -78.87; 1076m), the locality of one of the specimens (MZUTI 3322) examined here.

Description

Relatively small-sized snakes (276–524mm SVL) with 23–25 maxillary teeth, 10–13 infralabials, 8 or 9 supralabials, 1–3 postoculars with the lower occasionally resembling a subocular and the middle occasionally resembling a temporal, fused prefrontals, internasals in contact, loreal present, incomplete nuchal collar present in juveniles (MZUTI 3322) fading ontogenetically, 181–197 ventrals, 131–141 subcaudals, (19–21)-19-17 dorsal scale rows, strong keels present on dorsal scales, and enlarged, bicarinate vertebral scale row. Uniformly cream-colored venter and dark-brown to black dorsum. Lumbar vertebrae are constricted near the middle, zygapophyses and neural spines are not expanded. The hemipenis has been briefly described (Bogert 1964), but prior to modern classifications of the organ (Zaher 1999), and needs to be examined in more detail. Ranges at low to middle elevations (~300–1600m) along the Pacific versant from the Darien in Panama to central Ecuador.

Etymology

Most likely after Moritz Wagner, who collected the holotype (see Bauer 2013), and not Johann Andreas Wagner as suggested by previous authors (Beolens et al. 2011).

Notes

The re-description and neotype designation (NMW 18915) of Werner (1901) have no nomenclatural validity (see Bogert 1964).

Emmochliophis Fritts & Smith, 1969

Emmochliophis fugleri Fritts & Smith, 1969 (type species by monotypy)

Emmochliophis miops (Boulenger, 1898)

Etymology

From the Greek emmochlion for “a socket for a bar” and ophis for “snake,” referring to the unique interlocking vertebrae (Fritts and Smith 1969).

Description

Relatively small-sized (~250mm SVL) terrestrial snakes restricted to the Pacific Andean slopes of NW Ecuador, with a small number (<17) of maxillary teeth, 8 supralabials, 8 infralabials, fused prefrontals, internasals in contact, loreal absent, fewer than 150 ventrals, fewer than 100 subcaudals, dorsal scales in 19 rows without reduction, trunk vertebrae with lateral expansion of the zygapophyses, and expanded zygapophyses forming a rod-and-groove mechanism in Emmochliophis fugleri, but not in E. miops.

Notes

Both species are known only from the types. The hemipenis of E. fugleri has been briefly described (Fritts and Smith 1969), but prior to modern classifications of the organ (Zaher 1999), and needs to be examined in more detail. The organ is unknown in E. miops, as the sole known specimen is female (Sheil 1998).

Emmochliophis fugleri Fritts & Smith, 1969

Holotype

UIMNH 78795, 4 km. E Río Baba bridge, 24 km. S Santo Domingo de los Colorados, Pichincha, Ecuador, ~600 m.

Etymology

After Dr. Charles Fugler, who collected the holotype.

Description

A terrestrial snake from the Pacific Andean slopes of NW Ecuador, diagnosable by 16 maxillary teeth, 8 infralabials, 8 supralabials, 2 postoculars, internasals in contact, loreal absent, nuchal collar absent, 140 ventrals, 97 subcaudals, dorsal scales in 19 rows without reduction, strong keels, and zygapophyses expanded laterally forming rod–and–bar assembly. Type locality is surrounded by banana plantations. Little else is known about the habits or habitat of the species.

Notes

Known only from the type specimen, a male, collected by C. Fugler in February 1966.

Emmochliophis miops (Boulenger, 1898)

Synophis miops Boulenger, 1898

Holotype

BMNH 1946.1.12.30, Paramba, Ecuador (=Parambas, Imbabura fide Lynch and Duellman 1997)

Etymology

None given by Boulenger (1898); likely from the Greek miops for “myopia,” in reference the species’ small eyes, given as diagnostic by Boulenger.

Description

Relatively small-sized (~250mm SVL) terrestrial snake from the Pacific Andean slopes of NW Ecuador, diagnosable by 13 maxillary teeth, 8 infralabials, 8 supralabials, 1 postocular, internasals in contact, loreal absent, nuchal collar present, 145 ventrals, 93 subcaudals, dorsal scales in 19 rows without reduction, strong keels, and lateral expansion of the zygapophyses. Type locality is humid subtropical lower montane forest. Little else is known about the habits or habitat of the species. Stomach of type specimen contains remains of a gymnophthalmid lizard (Sheil 1998).

Notes

Known only from the type specimen, a female, collected by W. F. H. Rosenberg in October 1897. The type specimen was re-described in great detail by Sheil (1998).

Synophis Peracca, 1896

Synophis bicolor Peracca, 1896 (type species by monotypy)

Synophis calamitus Hillis, 1990

Synophis lasallei (Nicéforo-Maria, 1950)

Synophis plectovertebralis Sheil & Grant, 2001

Synophis zaheri Pyron, Guayasamin, Peñafiel, Bustamante, & Arteaga, 2015

Etymology

None given by Peracca (1896); presumably from the Greek syn- for “with” or “together” and ophis for “snake,” though the intended meaning of “with snake” is unclear.

Description

Relatively small-sized (~300mm SVL) dipsadine snakes of the Andes and Chocó of Colombia and Ecuador, with 16–27 maxillary teeth, 7–11 infralabials, 7–9 supralabials, fused prefrontals, loreal present, 1 or 2 postoculars, 144–184 ventrals, 88–138 subcaudals, dorsal scales in (19–21)-(17–21)-(17–20) rows, neural spine expanded and flattened, laterally expanded zygapophyses, and hemipenes slightly bilobed, semicalyculate, and semicapitate, relatively stout and bulbous, covered in large spines or hooks.

Notes

On the basis of similar scale counts, but apparently without examining specimens, Amaral (1929) considered the holotype of Synophis bicolor (at the time, the only known specimen from the only known species) to be synonymous with Diaphorolepis wagneri. These snakes are extremely rare, accounting for the paucity of knowledge and unclear species-boundaries. Numerous undescribed species from many new localities are known, and await description (pers. comm., T. Grant, E. Meneses-Pelayo, O. Torres-Carvajal, and J. Arredondo).

Synophis bicolor Peracca, 1896

Holotype

MZUT 257, locality given only as “South America.”

Etymology

None given by Peracca (1896); presumably from the Greek bi-color for “two colors,” referring to the dark dorsum and light venter.

Description

Small-sized (~200–400mm SVL) dipsadine snakes of the Andes and Chocó of Colombia and Ecuador, diagnosable by 16–27 maxillary teeth, 9–12 infralabials, 8 or 9 supralabials, fused prefrontals, loreal present, 2 postoculars, 152–193 ventrals, 96–143 subcaudals, dorsal scales in (19–21)-(17–19)-(17–18) weakly keeled rows, neural spine expanded and flattened, laterally expanded zygapophyses, and hemipenes slightly bilobed, semicalyculate, and semicapitate, relatively stout and bulbous, covered in large spines or hooks. Populations of this species are found in both lowland Chocóan rainforest and Andean cloud forests. Individuals are often found in leaf litter or in bushes, active at night. One collection from the Pacific Andean slopes of Ecuador (UMMZ 185886–185891) represents clutches of 2, 2, and 8 eggs, with hatchlings 125–132mm SVL. Nothing is known of diet.

Notes

This is a species complex comprising at least three species-level taxa, which are distinct genetically, geographically, and morphologically (Figs 1, 3D, 4, 7, 9; Tables 13).

First are the Ecuadorean Andean highlands populations (Synophis aff. bicolor), which occur both on both the Pacific and Andean versants (~800–1700m). These are diagnosable by number of ventrals (152–166), subcaudals (96–122), infralabials (10 or 11), and supralabials (8 or 9), in combination. One individual (UMMZ 91550) has 24/27 maxillary teeth. The southernmost individual we examined (MZUTI 4180) has a very low number of ventral scales (152) compared to the remaining populations (160–166). Populations east and west of the Andes may also be a distinct species (O. Torres-Carvajal, pers. comm.), and are presented separately here. Most records from the Pacific versant north of the Río Toachi appear to represent S. calamitus (see below); one specimen reported from north of the river (BMNH 1940.2.30.31) may be mis-labeled, mis-identified, or the locality mis-referenced, or the species may be sympatric at some localities north of the river.

Second are the Chocóan populations from NW Ecuador, and presumably SW Colombia (~200–300m). These match the holotype in having 174–183 ventrals, 129–138 subcaudals, 8 supralabials, and typically 9 infralabials, though one specimen from further south (MZUTI 4175) has 11. We revise the type locality of Synophis bicolor by subsequent restriction (sensu Smith 1953) to Tobar Donoso, Carchi Province, Ecuador (1.19, -78.50), locality of several specimens examined here (Tables 1, 2; Figs 1, 4, 7, 9), to cement this association. Thus, this population represents S. bicolor sensu stricto in the case of future revision.

Third are the Colombian Andean highland populations (~1400–1500m; see Nicéforo-Maria 1970), which differ from the holotype in having 184–193 ventrals (versus 180), 127–131 subcaudals (versus 136), and 10–12 infralabials (versus 9). This group likely represents a third species, Synophis cf. bicolor. While we refrain from describing these additional S. bicolor-group species here based on limited current sampling, the populations described above likely represent at least two (Ecuadorean Andean highland and Colombian Andean Highland) if not three (E and W Ecuadorean and Colombian Andean highland) species.

Synophis calamitus Hillis, 1990

Holotype

KU 197107, 4 km SE Tandayapa, Pichincha Province, Ecuador.

Paratype. KU 164208, 9km SE Tandayapa, Pichincha Province, Ecuador.

Etymology

From the Latin for “calamity,” referring to accidents that befell the original collectors (Hillis 1990).

Description

A group of relatively small (~450mm SVL) dipsadine snakes of the cloud forests of the Pacific versant of the Andean highlands of Ecuador diagnosable by 9–11 infralabials, 7–9 supralabials, fused prefrontals, internasals separated, loreal present, 1 or 2 postoculars, 163–166 ventrals, 110–125 subcaudals, dorsal scales in (21–23)-19-17 weakly keeled rows, neural spine expanded and flattened, and laterally expanded zygapophyses. Known from middle to high-elevation (~1900–2200m) cloud forests north of the Río Toachi. Nothing is known of diet or reproduction.

Notes

A detailed description was also provided by Hillis (1990). The hemipenes have likely not been examined. Easily confused with Synophis bicolor; at least one specimen (QCAZ 11931) from near the type locality was originally mis-identified (O. Torres-Carvajal, pers. comm.). We suggest that all populations north of the Río Toachi are likely to represent S. calamitus. As mentioned above, one specimen apparently matching S. bicolor (BMNH 1940.2.30.31) is known from Río Soloya near Mindo north of Río Toachi, but this may have been mis-labeled, or mis-referenced geographically. The specimen of S. bicolor examined by Zaher (1999), QCAZ 452, cannot be located (O. Torres-Carvajal, pers. comm.), but originates from Chiriboga, Pichincha Province, Ecuador, north of Río Toachi, and thus may represent an S. calamitus. If this is the case, the hemipenes of S. calamitus and S. lasallei are nearly identical (Zaher 1999; Martinez 2011). Finally, one specimen sequenced here from Tambo Tanda (MZUTI 3694) appears to have aberrantly subdivided head scales, possessing one extra postocular, and 2 extra supralabials and infralabials (Fig. 8), which are misshapen and abnormally small. The badly damaged paratype also appears to have two postoculars on one side (O. Torres-Carvajal, pers. comm.). Thus, we concur with Hillis (1990) that one postocular, 7 or 8 supralabials, and 9 infralabials (along with the divided internasals and smooth anterior dorsal scale-rows) are generally diagnostic of the species, but with rare individual variation.

Synophis lasallei (Nicéforo-Maria, 1950)

Diaphorolepis lasallei Nicéforo-Maria, 1950

Holotype

MLS/CJSP uncat., from N of Albán, cen. Cundinamarca Dept., cen. Colombia.

Etymology

After the Instituto de La Salle, in Bogotá (Nicéforo-Maria 1950).

Description

Smaller (~300mm SVL) dipsadine snakes of the Amazonian versant of the Andes of Ecuador and Colombia, diagnosable by 24 maxillary teeth, 10 or 11 infralabials, 7–9 supralabials, fused prefrontals, internasals in contact, loreal present, 1 or 2 postoculars, nuchal collar absent, 144–165 ventrals, 101–126 subcaudals, dorsal scales in (19–23)-(19–22)-(17–21) strongly keeled rows even on head and neck, venter dark in some populations, neural spines expanded and flattened, and laterally expanded zygapophyses. Known from low to high elevations (~500–2000m) along the Amazonian versant of the Andes from central Colombia to central Ecuador. Nothing is known of diet or reproduction.

Notes

The hemipenes are very similar to both Diaphorolepis and S. bicolor (Bogert 1964; Zaher 1999; Martinez 2011). Much like Synophis bicolor, this species as currently described has a large geographic and elevational range, with wide variation in phenotype. There is significant variation in the number of dorsal scale rows and reduction thereof. One specimen from Ecuador (MCZ R-156873) has only one postocular and 7 supralabials, but otherwise matches the species. All other specimens have 2 and 8, respectively. Another specimen from Ecuador (MECN 2220) has 165 ventrals and 117 subcaudals with 19-19-17 scale rows, and is thus indistinguishable from S. aff. bicolor, with the exception of the strong keels on the nuchal scales and geographic distance from the nearest highland populations of S. aff. bicolor. All other specimens of S. lasallei have 144–156 ventrals, and most have (21–23)-(21–22)-(19–21) dorsal scale rows. Thus, it seems exceptionally likely that this is a species complex, possibly divided between highland and lowland, or northern and southern populations.

Synophis plectovertebralis Sheil & Grant, 2001

Holotype

UVC 11858, from Hacienda San Pedro, about 6 km south El Queremal, Municipio Dagua, Departamento del Valle del Cauca, Colombia.

Paratype

UVC 11580, from type locality.

Etymology

From the Latin plecto- for “braided” or “woven” and veretbralis for “vertebrae,” referring to the appearance of the interlocking zygapophyses viewed from above (Sheil and Grant 2001).

Description

Relatively small (~200mm SVL) dipsadine snakes of the Pacific versant of the Andean Highlands of W Colombia, diagnosable by 24 maxillary teeth, 7 or 8 infralabials, 7 or 8 supralabials, fused prefrontals, internasals in contact, loreal present, 1 postocular, nuchal collar present, 144–147 ventrals, 79–91 subcaudals, dorsal scales in 19-19-17 weakly keeled rows, neural spines expanded and flattened, and laterally expanded zygapophyses forming a partially interlocking complex. The type locality is a middle elevation (~1800m) cloud forest. Both known specimens were collected in moist leaf litter; one was active at night. The stomach of the holotype contained a Ptychoglossus stenolepis (Sauria: Gymnophthalmidae).

Notes

Known only from the holotype and paratype (apparently juveniles), though other material has apparently been collected in Colombia, near the type locality (T. Grant and E. Meneses-Pelayo, pers. comm.). The hemipenes have not been examined. A more detailed description of the two specimens is provided by Sheil and Grant (2001).

Given our restriction of the name, we also provide the following re-description of the re-delimited Nothopsini. Note that we have not performed a comparative examination of a large series of preserved material, and these data are summarized from the literature (Dunn and Dowling 1957; Savage 2002; Kohler 2008; McCranie 2011) to provide a basis for future revisions.

Nothopsini Cope, 1871

Genus Nothopsis Cope, 1871 (type genus by monotypy)

Nothopsis rugosus Cope, 1871

Nothopsis affinis Boulenger, 1895 (Holotype BMNH 1946.1.15.62, “Salidero, NW Ecuador, 350ft”) [subjective junior synonym of N. rugosus fide Dunn & Dowling 1957]

Nothopsis torresi Taylor, 1951 (Holotype KU 28710, “’Morehead’ Finca, 5 miles southwest of Turrialba, Costa Rica”) [subjective junior synonym of N. rugosus fide Dunn & Dowling 1957]

Holotype

USNM 12427, type locality “Isthmus of Darien [Panama]”

Etymology

From the Greek nothos for “bastard” and opsis for “appearance,” with Cope (1871) apparently referring to putative mimicry of Bothrops atrox.

Description

A relatively small-sized (<350mm SVL) dipsadine snake, ranging in Central and South America from Honduras to Colombia and Ecuador, in lowland and middle-elevation rainforests, 250-900m, distinguishable from nearly all other similar or related snakes in the area by the rugose, granular nature of the dorsal scales, in particular lacking differentiation of the cephalic scales with the exception of well-defined internasals and poorly defined frontal and parietals, which are separated by rows of irregular, undifferentiated scales. Color pattern consists of irregular and poorly defined blotches of blackish or light, dark, and yellowish brown. With respect to the characters described here for diaphorolepidine species, Nothopsis rugosus typically exhibits 19–21 maxillary teeth, 9–13 supralabials, 11–16 infralabials, 149–162 ventrals, 81–112 subcaudals, dorsal scales in (24–30)-(26–30)-(22–26) rows, SVL of 151–320mm, and tail length of 61–133mm (see Dunn and Dowling 1957).

Notes

This taxon has historically been divided up into as many as three species (see Dunn and Dowling 1957), though only a single species is currently recognized. There may be cryptic variation or undiscovered diversity within this group. Note that the family name was originally spelled Nothopidae by Cope (1871), but –ops– is the correct stem from –opsis, and Nothopsidae (and Nothopsini) is thus the correct spelling, as adopted by later authors.

Discussion

Systematics of Diaphorolepidini and Nothopsini

Corroborating previous results, we find that current supra-generic classification in Dipsadinae does not accurately reflect the phylogeny and describe natural groups in many cases (Pyron et al. 2011; Grazziotin et al. 2012). Support for monophyly and placement of many genera is low, and many other genera are apparently non-monophyletic. Efforts to clarify this situation are underway, sampling more taxa and characters (F. Grazziotin, pers. comm.). Only ~250 out of ~900 dipsadine species (Wallach et al. 2014) are sampled here for a few genes, but cryptic and undiscovered diversity is likely much higher in the group, and will require extensive additional sampling of taxa and characters to arrive at a stable phylogenetic and taxonomic resolution. The taxonomy of Dipsadinae has been contentious for quite some time (Cadle 1984a,b,c; Zaher 1999; Zaher et al. 2009; Grazziotin et al. 2012; Sheehy 2012), and will likely require extensive additional sampling of taxa and characters to provide a stable taxonomic resolution.

In particular, we find that Nothopsini is not monophyletic as historically defined, but that Nothopsis is strongly nested within a primarily Central American clade, with Imantodes and Leptodeira. We restrict tribe Nothopsini Cope, 1871 to Nothopsis. We resurrect and re-delimit Diaphorolepidini Jenner, 1981 to include only Diaphorolepis, Emmochliophis, and Synophis. Whereas Emmochliophis remains unsampled in the molecular phylogeny, it appears to be the sister-taxon of Synophis based on morphological data (Hillis 1990). However, our phylogeny suggests that many of the morphological characters previously used to define supra-generic groups in Dipsadinae (see Savitzky 1974; Wallach 1995) are subject to strong and rapid convergence. Thus, future studies may find an alternative placement for this genus. Finally, the genus Xenopholis is weakly nested within a primarily South American clade, and remains Dipsadinae incertae sedis.

Species limits in Diaphorolepidini

Larger sample sizes reveal expanded ranges of diagnostic characters previously used to delimit species in Diaphorolepidini. These will hopefully assist future researchers in describing new taxa, and re-delimiting species boundaries. In particular, both Synophis bicolor and S. lasallaei may comprise multiple distinct species. Additional DNA sequencing and meristic and mensural measurements of more specimens should help clarify taxonomic boundaries.

In the case of Synophis bicolor, the Chocóan populations in Ecuador and presumably nearby Colombia match the description of the holotype, and thus likely represent the source of the original specimen, which remains to be re-described in detail. Contrastingly, highland populations in the Andean Highlands of Ecuador and Colombia are morphologically and genetically distinct, and both likely represent undescribed species. In the Ecuadorean Andes, populations of this taxon occur on both the Pacific and Amazonian versants, which may also be distinct from each other. The sampled specimen of S. lasallei is weakly nested within the sampled specimens of S. bicolor. A wide range of squamation and color pattern is observed in S. lasallei, which may represent cryptic species, as well as potential mis-identification of examined specimens. Finally, a cloud-forest population from the Pacific versant in SW Ecuador represents a new species described here as S. zaheri, allied to S. calamitus. Understanding the geographic distribution and genetic diversity in these taxa will require additional genetic sampling, which is hampered by the rarity of these species.

One of the most distinctive features of diaphorolepidine species is the highly modified condition of the vertebrae, in which the prezygapophyses and postzygapophyses are broadly expanded, forming ridges, and occasionally interlocking (Bogert 1964; Fritts and Smith 1969; Hillis 1990). Given the difficulty of preparing the skeletal material and the extreme rarity of specimens, this was not examined for S. zaheri or any additional specimens examined here. However, this may be a crucial character for future systematic revisions in the group, possibly utilizing micro-CT scanning or radiography.

Another possible source of information for delimiting species are the hemipenes. The organs are highly similar in Diaphorolepis and most Synophis species (Bogert 1964; Jenner 1981; Hillis 1990; Zaher 1999). Our observations agree with previous authors that the hemipenes are not strongly differentiated among species, though larger comparative series may reveal characters that serve to better diagnose species-level groups. In particular, the hemipenes are “nearly identical” in S. bicolor and S. lasallei (Zaher 1999; Martinez 2011), and our examination of S. zaheri shows no obvious qualitative differences. It is possible that speciation is primarily ecological or allopatric in this group, and thus there is little physical reproductive isolation.

Conclusions

Higher-level taxonomy in Dipsadinae is still partially unresolved, and many genera and supra-generic groups are either non-monophyletic, or poorly supported and weakly placed. This includes Nothopsini Cope, 1871, which must be restricted to Nothopsis, if it is used at all. We resurrect and re-delimit Diaphorolepidini Jenner, 1981 to include only Diaphorolepis, Emmochliophis, and Synophis. The genus Xenopholis remains Dipsadinae incertae sedis. Revised and expanded diagnoses in Diaphorolepidini support the distinctiveness of all currently recognized taxa. Cryptic species are likely present in S. bicolor and S. lasallei. A new population from the cloud forest of SW Ecuador is morphologically and genetically distinct, and we here name it S. zaheri. We hope that these data will provide a robust platform for future researchers to examine species boundaries in Diaphorolepidini, as additional work clearly remains to be done. This is hampered, however, by the extreme rarity of these species.

Acknowledgments

This research was funded in part by the George Washington University (including a grant of time from the Colonial One HPC Initiative), Universidad Tecnológica Indoamérica, and U.S. NSF grants DBI-0905765 and DEB-1441719 to R.A.P. Permits were provided by the Ministerio del Ambiente, Ecuador. We thank T. J. Hibbitts (TCWC), J. Martinez and J. Losos (MCZ), J. A. Campbell, C. J. Franklin, and E. N. Smith (UT Arlington), C. M. Sheehy III (UF), F. Andreone (MZUT), C. Sheil (JCU), T. Grant (USP), A. Savitzky (USU), H. Grillitsch and G. Gassner (NMW), G. Schneider and D. Rabosky (UMMZ), D. Hillis, D. Cannatella, and T. LaDuc (UT Austin), J. Jacobs and K. de Queiroz (NMNH), H. Zaher and F. Grazziotin (MZUSP), J. Daza and J. Arredondo (MHUA), O. Torres-Carvajal (QCAZ), J. Valencia (FHGO), M. Yánez-Muñoz (MECN), J. Culebras (UTI), and D. Troya, D. Mideros, J. Castillo, and R. Hidalgo for access to specimens, data, and pictures.

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Appendix I

GenBank accession numbers for Dipsadinae and outgroup species analyzed here.

Species 12S 16S CYTB ND4 CMOS
Adelphicos quadrivirgatum - - GQ895853 - GQ895796
Alsophis antiguae AF158455 AF158524 - - -
Alsophis antillensis FJ416691 FJ416702 FJ416726 FJ416800 -
Alsophis manselli - AF158528 FJ416727 FJ416801 -
Alsophis rijgersmaei FJ416697 FJ416708 FJ416729 FJ416803 -
Alsophis rufiventris FJ416698 FJ416709 FJ416730 FJ416804 -
Alsophis sajdaki - - FJ416731 FJ416805 -
Alsophis sibonius FJ416692 FJ416703 FJ416728 FJ416802 -
Amastridium sapperi - - GQ334479 GQ334580 -
Apostolepis albicollaris JQ598793 JQ598856 - - JQ598965
Apostolepis assimilis GQ457781 GQ457724 - - GQ457843
Apostolepis cearensis JQ598794 JQ598857 - - JQ598966
Apostolepis dimidiata GQ457782 GQ457725 JQ598917 - GQ457844
Apostolepis flavotorquata JQ598795 JQ598858 GQ895854 - GQ895798
Arrhyton dolichura AF158438 AF158507 FJ416721 FJ416795 -
Arrhyton procerum AF158452 AF158521 FJ416723 FJ416797 -
Arrhyton redimitum AF158439 AF158508 FJ416720 FJ416794 -
Arrhyton supernum AF158436 AF158505 FJ416718 FJ416792 -
Arrhyton taeniatum AF158453 AF158522 FJ416717 FJ416791 -
Arrhyton tanyplectum AF158446 AF158516 FJ416722 FJ416796 -
Arrhyton vittatum AF158437 AF158506 FJ416719 FJ416793 -
Atractus aff. iridescens MZUTI4122 - KT944037 KT944049 KT944056 -
Atractus albuquerquei GQ457783 GQ457726 JQ598918 - GQ457845
Atractus badius AF158425 AF158485 - - -
Atractus duboisi MZUTI62 - KT944041 - KT944059 -
Atractus dunni MZUTI2650 - KT944038 KT944050 KT944057 -
Atractus elaps - - EF078536 EF078584 -
Atractus flammigerus AF158402 AF158471 - - -
Atractus gigas MZUTI3286 - KT944043 KT944053 KT944061 -
Atractus iridescens MZUTI3758 - - KT944052 - -
Atractus iridescens MZUTI3759 - KT944039 KT944051 KT944058 -
Atractus major ANF1545 - KT944045 - - -
Atractus resplendens MZUTI3996 KT944036 KT944042 KT944055 KT944060 -
Atractus reticulatus JQ598798 JQ598886 - - JQ598970
Atractus schach JQ598799 AF158486 - - JQ598971
Atractus sp. MZUTI4178 - KT944040 - - KT944066
Atractus trihedrurus GQ457784 GQ457727 JQ598919 - GQ457846
Atractus typhon MZUTI3284 - KT944044 KT944054 KT944062 -
Atractus wagleri - - GQ334480 GQ334581 -
Atractus zebrinus JQ598800 JQ598861 - - JQ598972
Atractus zidoki AF158426 AF158487 - - -
Boiruna maculata GQ457785 JQ598862 GQ895855 - GQ895799
Borikenophis portoricensis FJ416696 AF158517 AF471085 U49308 AF471126
Borikenophis variegatus FJ416700 FJ416711 FJ416734 FJ416808 -
Caaeteboia amarali GQ457807 GQ457747 JQ598921 - GQ457867
Calamodontophis paucidens GQ457786 GQ457728 - - GQ457848
Caraiba andreae AF158442 AF158511 FJ416743 FJ416817 -
Carphophis amoenus AY577013 AY577022 AF471067 - DQ112082
Carphophis vermis - - KP765656 - -
Clelia clelia AF158403 AF158472 - - JQ598973
Coluber constrictor L01765 L01770 EU180432 AY487040 AY486937
Coniophanes fissidens - - EF078538 EF078586 -
Conophis lineatus GQ457788 JQ598865 JQ598924 - JQ598975
Conophis vittatus - - GQ895861 - GQ895805
Contia longicaudae - - GU112407 GU112427 -
Contia tenuis AY577021 AY577030 GU112401 AF402658 AF471134
Crisantophis nevermanni GU018152 GU018169 - - -
Cryophis hallbergi - - GQ895863 EF078544 GQ895807
Cubophis cantherigerus AF158405 AF158475 AF544669 FJ416818 AF544694
Cubophis caymanus FJ416693 FJ416704 FJ416745 FJ416820 -
Cubophis fuscicauda FJ416695 FJ416706 FJ416747 FJ416822 -
Cubophis ruttyi FJ416699 FJ416710 FJ416746 FJ416821 -
Cubophis vudii AF158443 AF158512 FJ416744 FJ416819 -
Diadophis punctatus AF544765 AY577024 EU193700 EU193987 AF471122
Diaphorolepis wagneri MZUTI3322 - KR814752 - KR814775 KR814764
Diaphorolepis wagneri MZUTI3752 - KR814753 - KR814777 KR814766
Diaphorolepis wagneri MZUTI3901 - KR814754 - KR814778 KR814767
Dipsas albifrons JQ598803 JQ598866 JQ598925 - -
Dipsas articulata JQ598804 JQ598867 - - -
Dipsas catesbyi JQ598805 Z46496 JQ598926 EF078585 JQ598977
Dipsas indica GQ457789 GQ457730 - - GQ457850
Dipsas neivai GQ457790 GQ457731 - - GQ457851
Dipsas pratti - - GQ334482 GQ334583 -
Dipsas variegata AF158406 AF158476 - - -
Drepanoides anomalus GQ457791 GQ457732 GQ895866 - GQ895810
Echinanthera melanostigma JQ598806 GU018174 JQ598928 - -
Echinanthera undulata JQ598807 JQ598870 JQ598929 - JQ598978
Elapomorphus quinquelineatus GQ457794 GQ457735 JQ598930 - GQ457855
Erythrolamprus aesculapii GQ457795 GQ457736 GQ895871 - GQ895814
Erythrolamprus almadensis JQ598808 JQ598871 - - JQ598979
Erythrolamprus atraventer JQ598809 JQ598872 - - JQ598980
Erythrolamprus breviceps AF158464 AF158533 - - -
Erythrolamprus ceii JQ598810 JQ598873 - - JQ598981
Erythrolamprus cursor JX905310 JX905314 - - -
Erythrolamprus epinephelus GU018158 GU018176 - - -
Erythrolamprus jaegeri GQ457809 GQ457749 - - GQ457869
Erythrolamprus juliae AF158445 AF158514 - - -
Erythrolamprus miliaris JQ598811 AF158480 JQ598931 - JQ598982
Erythrolamprus mimus GU018157 GU018175 - - -
Erythrolamprus poecilogyrus JQ598812 JQ598875 - - -
Erythrolamprus pygmaeus GU018154 GU018172 - - -
Erythrolamprus reginae JQ598813 JQ598876 - - JQ598983
Erythrolamprus typhlus GQ457811 GQ457751 - - GQ457871
Farancia abacura Z46467 Z46491 U69832 DQ902307 AF471141
Farancia erytrogramma AY577017 AY577026 KP765663 - -
Geophis carinosus - - GQ895872 - GQ895815
Geophis dubius - - KC917319 - -
Geophis godmani JQ598814 JQ598877 JQ598932 - -
Geophis juarezi - - KC917315 - -
Geophis latifrontalis - - KC917322 - -
Geophis occabus - - KC917323 - -
Geophis turbidus - - KC917321 - -
Gomesophis brasiliensis GQ457796 GQ457737 - - -
Haitiophis anomalus FJ666091 FJ666092 - - -
Helicops angulatus GQ457797 GQ457738 AF471037 - AF471160
Helicops carinicaudus JQ598815 - - - JQ598984
Helicops gomesi GQ457798 GQ457739 - - GQ457858
Helicops hagmanni JQ598816 JQ598878 - - JQ598985
Helicops infrataeniatus GQ457799 GQ457740 JQ598933 - GQ457859
Heterodon nasicus GQ457801 AY577027 KP765664 - GQ457861
Heterodon platirhinos AY577019 AY577028 GU112412 AF402659 JQ598986
Heterodon simus AY577020 AY577029 AF217840 DQ902310 AF471142
Hydrodynastes bicinctus GQ457802 GQ457742 JQ598935 - GQ457862
Hydrodynastes gigas GQ457803 GQ457743 GQ895873 - GQ895816
Hydromorphus concolor - - GQ895874 - GQ895817
Hydrops triangularis GQ457804 GQ457744 AF471039 - AF471158
Hypsiglena affinis - - GU353241 EU363055 -
Hypsiglena chlorophaea EU728577 EU728577 EU728577 EU728577 -
Hypsiglena jani EU728592 EU728592 EU728592 EU728592 -
Hypsiglena ochrorhyncha EU728578 EU728578 EU728578 EU728578 -
Hypsiglena slevini EU728584 EU728584 EU728584 EU728584 -
Hypsiglena tanzeri - - EU728588 EU363044 -
Hypsiglena torquata EU728591 EU728591 EU728591 EU728591 AF471159
Hypsirhynchus callilaemus AF158440 AF158509 FJ416737 FJ416811 -
Hypsirhynchus ferox AF158447 AF158515 GQ895875 FJ416816 GQ895818
Hypsirhynchus funereus AF158451 AF158520 FJ416739 FJ416813 -
Hypsirhynchus parvifrons AF158441 AF158510 FJ416740 FJ416814 -
Hypsirhynchus polylepis AF158450 AF158519 FJ416738 FJ416812 -
Hypsirhynchus scalaris AF158449 AF158518 FJ416741 FJ416815 -
Ialtris dorsalis AF158456 AF158525 FJ416735 FJ416809 -
Ialtris haetianus AF158458 AF158527 FJ416736 FJ416810 -
Imantodes cenchoa EU728586 EU728586 EU728586 EU728586 GQ457865
Imantodes chocoensis - - KC176250 - -
Imantodes gemmistratus - - GQ334487 EF078557 -
Imantodes inornatus - - GQ334489 EF078559 -
Imantodes lentiferus AF158463 AF158532 KC176252 EF078561 -
Leptodeira annulata GQ457806 GQ457746 FJ416713 FJ416787 AF544690
Leptodeira bakeri - - GQ334518 GQ334618 -
Leptodeira frenata - - EF078532 EF078580 -
Leptodeira maculata - - GQ334524 GQ334623 -
Leptodeira nigrofasciata - - GQ334526 EF078581 -
Leptodeira polysticta EU728590 EU728590 EU728590 EU728590 -
Leptodeira punctata - - EF078530 EF078577 -
Leptodeira rubricata - - GQ334527 GQ334631 -
Leptodeira septentrionalis GU018148 GU018163 KC176243 KC176255 -
Leptodeira splendida - - EF078521 EF078569 -
Leptodeira uribei - - EF078531 EF078579 -
Lygophis anomalus JQ598817 JQ598879 - - -
Lygophis elegantissimus GQ457808 GQ457748 - - GQ457868
Lygophis flavifrenatus JQ598818 JQ598880 - - -
Lygophis lineatus - - - - DQ469789
Lygophis meridionalis GQ457810 GQ457750 - - GQ457870
Lygophis paucidens JQ598819 - - - JQ598987
Magliophis exiguum FJ416694 AF158526 AF471071 FJ416798 AF471117
Magliophis stahli - - FJ416725 FJ416799 -
Manolepis putnami JQ598820 JQ598881 JQ598936 - JQ598988
Mussurana bicolor GQ457787 GQ457729 - - GQ457849
Ninia atrata GQ457814 JQ598882 JQ598937 GQ334659 GQ457874
Nothopsis rugosus ASL493 GU018159 GU018177 - - -
Nothopsis rugosus MZUTI3682 - KR814760 KR814770 KR814779 KR814768
Oxyrhopus clathratus GQ457815 GQ457754 - - GQ457875
Oxyrhopus formosus JQ598821 AF158482 - - -
Oxyrhopus guibei JQ598822 JQ627291 JQ598938 - JQ598989
Oxyrhopus melanogenys JQ598823 AF158489 - - JQ598990
Oxyrhopus petolarius GU018144 GU018170 GQ334554 GQ334660 -
Oxyrhopus rhombifer GQ457816 GQ457755 - - GQ457876
Oxyrhopus trigeminus JQ598824 JQ598884 JQ598939 - -
Paraphimophis rusticus JQ598802 JQ598864 JQ598923 - JQ598974
Phalotris bilineatus JQ598827 JQ598887 JQ598943 - -
Phalotris lativittatus JQ598825 JQ598885 - - JQ598991
Phalotris lemniscatus GQ457817 GQ457756 JQ598941 - GQ457877
Phalotris mertensi JQ598826 - - - -
Phalotris nasutus GQ457818 GQ457757 GQ895880 - GQ895822
Philodryas aestiva GQ457819 GQ457758 - - GQ457879
Philodryas agassizii GQ457823 GQ457762 GQ895883 - GQ457883
Philodryas argentea GQ457842 GQ457780 JQ598944 - GQ457899
Philodryas baroni JQ598828 JQ598888 - - -
Philodryas georgeboulengeri - - GQ895898 - GQ895838
Philodryas mattogrossensis GQ457820 GQ457759 - - GQ457880
Philodryas nattereri JQ598829 JQ598889 AF236806 - JQ598992
Philodryas olfersii JQ598830 AF158484 JQ598945 - JQ598993
Philodryas patagoniensis GQ457821 JQ627296 AF236808 - GQ457881
Philodryas psammophidea GU018149 GU018168 - - -
Philodryas viridissima AF158419 AF158474 AF236807 - -
Phimophis guerini GQ457822 GQ457761 - - GQ457882
Pseudalsophis dorsalis JQ598832 JQ598892 JQ598946 - JQ598994
Pseudalsophis elegans AF158401 AF158470 JQ598947 - JQ598995
Pseudoboa coronata GQ457824 GQ457763 - - GQ457884
Pseudoboa neuwiedii AF158423 AF158490 GQ895884 - GQ895825
Pseudoboa nigra AF544775 GQ457764 JQ598948 - AF544729
Pseudoeryx plicatilis GQ457826 GQ457765 GQ895885 - GQ895826
Pseudoleptodeira latifasciata EU728579 EU728579 EU728579 EU728579 -
Pseudotomodon trigonatus GQ457827 GQ457766 - - GQ457887
Psomophis genimaculatus GQ457828 GQ457767 - - GQ457888
Psomophis joberti GQ457829 GQ457768 GQ895887 - GQ895828
Psomophis obtusus JQ598836 JQ598896 - - -
Ptychophis flavovirgatus GQ457830 GQ457769 - - GQ457890
Rhachidelus brazili JQ598837 JQ598897 JQ598952 - -
Rhadinaea flavilata - - AF471078 - AF471152
Rhadinaea fulvivittis - - EF078539 EF078587 -
Rodriguesophis iglesiasi JQ598831 JQ598891 GQ895881 - GQ895823
Sibon nebulatus EU728583 EU728583 EU728583 EU728583 AF544736
Sibon noalamina - KP209376 - - -
Sibynomorphus mikanii GQ457832 JQ627297 JQ598954 - GQ457892
Sibynomorphus neuwiedi JQ598838 JQ598898 - - -
Sibynomorphus turgidus JQ598839 JQ598899 - - -
Sibynomorphus ventrimaculatus JQ598840 JQ598900 - - JQ598997
Siphlophis cervinus JQ598841 JQ598901 GQ895888 - JQ598998
Siphlophis compressus GQ457833 GQ457772 - - GQ457893
Siphlophis longicaudatus JQ598842 JQ598902 - - JQ598999
Siphlophis pulcher GQ457834 GQ457773 JQ598955 - GQ457894
Sordellina punctata JQ598843 JQ598903 JQ598956 - JQ599000
Stichophanes ningshaanensis KJ719252 KJ719252 KJ719252 KJ719252 KJ638718
Synophis bicolor MZUTI4180 - KT944048 - KT944065 KT944069
Synophis bicolor MHUA14577 KR814751 KR814758 KR814773 - KR814769
Synophis bicolor MZUTI3529 - KR814759 KR814771 KR814780 KR814762
Synophis bicolor MZUTI4175 - KT944046 - KT944063 KT944067
Synophis bicolor UTA R-55956 - - JX398697 JX398557 -
Synophis calamitus KU197107 KR814622 KR814640 KR814697 KR814711 KR814663
Synophis calamitus MZUTI3694 - KR814755 KR814772 KR814774 KR814765
Synophis lasallei MZUTI4181 - KT944047 - KT944064 KT944068
Synophis zaheri MZUTI3353 - KR814756 - KR814776 KR814761
Synophis zaheri MZUTI3355 - KR814757 - KR814781 KR814763
Tachymenis peruviana GQ457835 GQ457774 - - GQ457895
Taeniophallus affinis JQ598844 JQ598905 JQ598957 - GQ457853
Taeniophallus brevirostris GQ457793 GQ457734 JQ598958 - GQ457854
Taeniophallus nicagus JQ598845 JQ598906 - - JQ599001
Tantalophis discolor - - EF078541 EF078589 -
Thalesius viridis AF158468 AF158538 - - -
Thamnodynastes hypoconia JQ598846 - - - -
Thamnodynastes lanei GQ457836 GQ457775 - - -
Thamnodynastes pallidus GU018155 GU018166 - - -
Thamnodynastes rutilus GQ457837 GQ457776 - - GQ457896
Thamnodynastes strigatus JQ598847 JQ598907 JQ598959 - -
Thermophis baileyi - - EU864148 KF595097 EU496922
Thermophis zhaoermii GQ166168 GQ166168 GQ166168 GQ166168 KF514882
Tomodon dorsatum GQ457838 GQ457777 GQ895892 - GQ895833
Tretanorhinus nigroluteus - - GQ895893 - GQ895834
Trimetopon gracile GU018160 GU018178 - - -
Tropidodipsas sartorii - - EF078540 EF078588 -
Tropidodryas serra JQ598848 JQ598908 JQ598961 - -
Tropidodryas striaticeps GQ457839 GQ457778 AF236811 - -
Uromacer catesbyi AF158454 AF158523 FJ416714 FJ416788 -
Uromacer frenatus AF158444 AF158513 FJ416715 FJ416789 -
Uromacer oxyrhynchus FJ416701 FJ416712 FJ416716 FJ416790 -
Xenodon dorbignyi GQ457812 GQ457752 - - GQ457872
Xenodon guentheri JQ598849 JQ598909 - - -
Xenodon histricus GQ457813 GQ457753 JQ598962 - GQ457873
Xenodon matogrossensis JQ598850 JQ598910 - - -
Xenodon merremi GQ457840 JQ598911 JQ598963 - GQ457898
Xenodon nattereri JQ598851 JQ598912 - - -
Xenodon neuwiedii GQ457841 GQ457779 AF236814 - -
Xenodon pulcher JQ598852 JQ598913 - - -
Xenodon semicinctus GU018156 GU018173 GQ895877 - -
Xenodon severus JQ598853 Z46474 JQ598964 - -
Xenopholis scalaris GFM825 - JQ598915 - - -
Xenopholis scalaris JPV GU018145 GU018164 - - -
Xenopholis scalaris KU222204 - - GQ895897 - GQ895837
Xenopholis scalaris WED57797 JQ598854 - - - JQ599002
Xenopholis undulatus R6955 JQ598855 JQ598916 - - JQ599003