Research Article |
Corresponding author: Pablo J. Venegas ( pvenegas@corbidi.org ) Academic editor: Alexander Haas
© 2021 Pablo J. Venegas, Germán Chávez, Luis A. García-Ayachi, Vilma Duran, Omar Torres-Carvajal.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Venegas PJ, Chávez G, García-Ayachi LA, Duran V, Torres-Carvajal O (2021) A new species of wood lizard (Hoplocercinae, Enyalioides) from the Río Huallaga Basin in Central Peru. Evolutionary Systematics 5(2): 263-273. https://doi.org/10.3897/evolsyst.5.69227
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We report the discovery of a new species of Enyalioides from the premontane forest of the Río Huallaga basin in central Peru. The most similar and phylogenetically related species are E. binzayedi and E. rudolfarndti. However, the new species differs from E. binzayedi (state of character in parentheses) by having dorsal scales strongly keeled on paravertebral region and feebly keeled or smooth elsewhere (prominent medial keel on each dorsal scale), more dorsals in transverse row between dorsolateral crests at midbody 26–39, x̄ = 30.44 (22–31, x̄ = 27.57), and a conspicuous posteromedial black patch in the gular region of males (absent). Contrarily, adult males of the new species and E. rudolfarndti are readily distinguished by having a conspicuous posteromedial black patch in the gular region, absent in E. rudolfarndti, and by lacking a conspicuous orange blotch (faint if present) on the antehumeral region, as in E. rudolfarndti. We also present an updated molecular phylogenetic tree of hoplocercines, which strongly supports both referral of the newly discovered species to Enyalioides and its status as distinct from those recognized previously.
Andes, Enyalioides, Hoplocercinae, Huallaga River, new species, Peru, phylogeny
The Huallaga drainage flows north from the Cordillera Oriental of central Peru and has an extension of 1,138 km (
In an effort to improve our knowledge on the herpetofauna of the Huallaga river basin, we carried out field surveys between 2011 and 2018, which led to the discovery of a new species of wood lizard described in this paper. Among hoplocercine lizards, wood lizards (Enyalioides) represent one of the South American lizard groups with the highest species discovery rate (corrected for clade size) of this century. Our discovery increases to 16 the number of known species of Enyalioides, of which only seven were known in previous centuries.
Most lizards were captured by hand during night. Coordinates and elevation were taken with a GPS (Garmin, WGS84). After the specimens were euthanized with T61 (Intervet), we took muscle tissue samples from the left thigh, and stored them in cryogenic vials (Axygen) at 96% ethanol. All collected specimens were fixed in 10% formalin for 48 hours and permanently stored in 70% ethanol. Voucher specimens were deposited at the herpetological collection of the Centro de Ornitología y Biodiversidad (
Snout-vent length (SVL) and tail length (TL) were measured with a ruler and recorded to the nearest millimeter. All other measurements (i.e., head width, length and height; rostral and mental width and height) were made with digital calipers and recorded to the nearest 0.1 mm. Sex was determined by noting the presence of hemipenes or sexually dichromatic characters. We followed the format of
Following laboratory protocols similar to those presented by
Editing, assembly, and alignment of sequences were performed with Geneious v9.1.8 (
Phylogenetic relationships were assessed under a Bayesian inference approach using MrBayes 3.2.7 (
The taxonomic conclusions of this study are based on the observation of morphological features and color patterns, as well as the inferred phylogenetic relationships. This information is considered as species delimitation criteria following a general lineage or unified species concept (
PERU • 1 ♂, adult; Huánuco department, Pachitea province, from the Huallaga River near Santa Rita Sur village; 9°35'33.7"S, 75°53'33.3"W, 856 m a.s.l. (above sea level); 27 Jun. 2011; P.J. Venegas leg.;
(28). PERU • 1 ♀, adult; same data as for holotype;
Enyalioides feiruzae can be distinguished from other species of Enyalioides, except E. binzayedi and E. rudolfarndti, by the combination of the following characters (see also Table
Summary of morphological characters and measurements (mm) of Enyalioides binzayedi, E. rudolfarndti, and E. feiruzae sp. n. Range (first line) and mean ± standard deviation (second line) are given for quantitative characters, except when there was no variation. Sample size between parentheses for femoral pores and maximum SVL.
Character | E. binzayedi | E. rudolfarndti | E. feiruzae |
---|---|---|---|
n = 7 | n = 4 | n = 29 | |
Vertebrals from occiput to base of tail | 40–55 | 42–47 | 41–56 |
48.00 ± 5.51 | 45.5 ± 2.38 | 47.75 ± 4.00 | |
Dorsals in transverse row between dorsolateral crests at midbody | 22–31 | 27–30 | 26–38 |
27.57 ± 3.64 | 28.25 ± 1.5 | 31.31 ± 3.03 | |
Ventrals in transverse row at midbody | 26–32 | 28–32 | 25–35 |
28.14 ± 2.12 | 30.25 ± 3.69 | 29.41 ± 3.36 | |
Transverse rows of ventrals between fore and hind limb | 30–39 | 35–38 | 32–39 |
35.29 ± 2.81 | 36.75 ± 1.5 | 36.79 ± 2.17 | |
Gulars | 27–31 | 33–36 | 27–38 |
29.14 ± 1.77 | 34.5 ± 1.29 | 32.75 ± 2.60 | |
Infralabials | 10–14 | 11 | 8–11 |
11.29 ± 1.50 | 11 | 9.44 ± 0.68 | |
Supralabials | 11–15 | 12–14 | 8–11 |
12.00 ± 1.41 | 12.5 ± 1.29 | 9.72 ± 0.59 | |
Canthals | 4–6 | 3–4 | 3–5 |
4.43 ± 0.79 | 3.75 | 3.89 ± 0.68 | |
Superciliaries | 13–14 | 14–18 | 12–17 |
13.57 ± 0.53 | 15.25 ± 1.89 | 14.13 ± 1.15 | |
Subdigitals manual digit IV | 17–22 | 19–23 | 18–24 |
19.86 ± 1.68 | 20 ± 2 | 20.13 ± 1.82 | |
Subdigitals pedal digit IV | 24–30 | 25–28 | 24–32 |
27.14 ± 2.48 | 26.5 ± 1.29 | 27.93 ± 2.13 | |
Femoral pores in males | 1–2 (n = 2) | 1 (n = 2) | 1 (n = 9) |
Femoral pores in females | 1–3 (n = 5) | 1 (n = 2) | 1 (n = 5) |
Tail length/total length | 0.56–0.60 | 0.60–1.49 | 0.47–0.63 |
0.58 ± 0.02 | 0.83 ± 0.44 | 0.59 ± 0.03 | |
Maximum SVL (mm) males | 118 (n = 2) | 116 (n = 2) | 122.0 (n = 9) |
Maximum SVL (mm) females | 122 (n = 5) | 90 (n = 1) | 119.1 (n = 5) |
A longitudinal row of strongly projecting scales along the lateral edge of the skull posterior and continuous with the superciliaries is also present in Enyalioides altotambo and E. oshaughnessyi, which occur west of the Andes in Ecuador and Colombia and differ from E. feiruzae in having smooth or slightly keeled dorsals. Additionally, Enyalioides cofanorum and E. microlepis share with the new species the presence of strongly keeled ventral scales and caudal scales of heterogeneous size on each autotomic segment. However, E. cofanorum differs from E. feiruzae (characters states in parentheses) in having a smaller body size, maximum SVL 107 mm in males and 109 mm in females (maximum SVL = 122 mm in males and 119 mm in females); scattered, projecting, large dorsal scales (absent); and a black patch covering the gular region (patch only covering the gular region posteromedially). Enyalioides microlepis differs from E. feiruzae in having more than 40 dorsal scales in a transverse line between the dorsolateral crest at midbody (38 or fewer dorsal scales); a low vertebral crest (high); and a blue gular background (white or orange).
Male (Fig.
Vertebral crest strongly projected and decreasing in size posteriorly, with vertebrals on neck at least four times higher than those between hind limbs; crest bifurcates at a point approximately 15 mm posterior to the cloaca, and extends onto tail about 1/3 its length; body flanks between fore and hind limbs with slight dorsolateral and ventrolateral folds, as well as oblique folds; scales on dorsolateral folds strongly keeled, slightly larger than adjacent scales; dorsal scales in paravertebral region enlarged, strongly keeled, and mucronate, decreasing in size as they approach the dorsolateral fold; scales on flanks slightly smaller than dorsals, keeled or smooth, nearly homogeneous in size except for some scattered enlarged keeled scales near both the ventrolateral region and the groins; ventral scales imbricate, strongly keeled, rectangular or rhomboid, with a posteromedial mucron; ventrals more than twice the size of dorsals.
Limb scales strongly keeled dorsally and keeled or feebly keeled ventrally; scales on dorsal aspect of thighs more or less homogeneous in size; scales on posterior aspect of thighs strongly heterogeneous in size, with most scales less than half the size of those scales on anterior and ventral aspects; subdigitals on finger IV 21; subdigitals on toe IV 27; one femoral pore on each side; tail laterally compressed and gradually tapering posteriorly; caudal scales keeled at the base of tail, becoming strongly keeled and imbricate towards tip, gradually increasing in size posteriorly on lateral and dorsal aspects of each caudal segment; caudals larger ventrally than dorsally; individual caudal segments three scales long ventrally and five scales long dorsally.
Color in life of holotype (Fig.
Color in ethanol 70%: Dorsal surface of body, head, limbs and tail grayish turquoise; dorsal surface of head and sides of head with a dusty brown tone and dark brown flecks; labials gray; dorsal surface of neck with a dusty brown tone, sides of neck with dark reticulations and a faint white postympanic stripe; vertebral scales on neck with dusty brown tips; dorsum with dark reticulations; tail with a dusty brown tone; dorsal surface of limbs with dark flecks and marks, more abundant on hind limbs; chin and throat cream, covered by a black patch on the posteromedial gular region and ventral surface of neck; chest, belly, ventral surface of limbs and tail dirty cream with faint marks on ventral surface of thighs.
Meristic and morphometric characters of Enyalioides feiruzae are summarized in Table
Adult specimens of Enyalioides feiruzae sp. nov. Male (A, B,
Juvenile specimens of Enyalioides feiruzae sp. nov. (A, B)
Head and anterior body region in lateral view of adult male specimens of Enyalioides feiruzae sp. nov. (A,
Among adult females (Fig.
Dorsal background in juveniles varies among different tones of brown and green (Fig.
Enyalioides feiruzae is known from the Huallaga River basin (Huánuco Department) on the Amazonian slope of the Andes of central Peru at elevations between 830–1,614 m a. s. l. Specimens from Pachitea and Huánuco provinces were collected in patches of secondary forest surrounded by pasturelands and coffee, corn or fruit plantations, whereas specimens from Tingo María National Park in Leoncio Prado province were found in a steep primary forest area.
The general landscape along the Huallaga River basin between the Huánuco and Pachitea provinces consists of steep areas, which are impacted by human activities like agriculture and cattle ranching, with scattered patches of secondary forest and narrow fringes of riverine forest. In contrast, Tingo María National Park is an area of primary forest, where the ground is covered by leaf litter, fallen trunks and rocks. Streams with small, torrential waterfalls are common. Vegetation includes lichens, ferns, orchids, epiphytes, bushes, and trees. All localities where Enyalioides feiruzae was collected lie within Peruvian Yungas (
Most individuals reported here were collected at night sleeping on vertical and horizontal stems of bushes 20–150 cm above the ground. One juvenile was found sleeping in the middle of a big leaf 30 cm above the ground. Another juvenile was found sleeping in a vertical stem, and when disturbed by the light of the headlamp, it dropped and ran to hide in a burrow under a big rock. Male
The specific name is a noun in the genitive case and is a patronym for Feiruz, a female green iguana, muse and lifelong friend, owned by Catherine Thomson from Farmington Hills, Michigan, USA, who supported our taxonomic research and nature conservation through the BIOPAT initiative.
Selected partitions and models were (i) tRNAs + 1st and 2nd codon positions of ND1, ND2 and COI [GTR+I+G]; (ii) 3rd codon position of ND1, ND2 and COI [GTR+I+G]. In agreement with previous hypotheses (
Distribution of Enyalioides binzayedi (triangles), E. feiruzae sp. nov. (circles), and E. rudolfarndti (squares) in Peru.
Phylogeny of Hoplocercinae. Maximum clade credibility tree based on a Bayesian analysis of mtDNA sequences. Posterior probabilities are indicated next to branches, except for short “intraspecific” branches (not shown for clarity). The new species described in this paper is shown in red. Outgroup taxa are not shown.
Interspecific mean genetic p-distances for the ND2 gene (Suppl. material
The phylogenetic tree presented here supports the position of the new species within the clade (E. azulae (E. palpebralis (E. sophiarothschildae (E. binzayedi (E. rudolfarndti, E. feiruzae sp. nov.))))), herein named “palpebralis group”, with maximal support (Fig.
The current landscape of the Huallaga River basin is the result of tectonic activity and climatic oscillations that occurred from the Late Oligocene to the Early Miocene (
The upper basin of the Huallaga River has been highly disturbed by agriculture activities (
We are grateful to Rafael Tamashiro of the environmental staff of Empresa de Generación Huallaga S.A., Luis Ríos of Consultores Asociados en Naturaleza y Desarrollo (CANDES), Daniel Cossios of Bioesfera and rangers of Tingo María National Park for their assistance and logistic support in the field. GC is grateful to his field companions A. Barboza, A. Beraun and D. Vasquez. The authors are indebted with C. Koch and G. Köhler for the review and comments on the manuscript. PJV is grateful to Rainforest Partnership for funding his herpetological research during 2021. OTC research was funded by The Systematics Association´s Systematics Research Fund, a Restricted Endowment Award from the Smithsonian Institution, the Secretaría de Educación Superior, Ciencia, Tecnología e Innovación del Ecuador (Arca de Noé Initiative, PIs Santiago Ron and OTC), and Pontificia Universidad Católica del Ecuador. Special thanks to Servicio Nacional de Areas Naturales Protegidas (SERNANP) for facilitating our research in Tingo María National Park through the “Convenio Específico de Cooperación Interinstitucional entre el Servicio Nacional de Áreas Naturales Protegidas por el Estado y la Empresa de Generación Huallaga S.A.” The authors are grateful to the Centrum für Naturkunde (CeNak) – Center of Natural History – University of Hamburg for supporting the publication of Evolutionary Systematics.
Material examined
Data type: note
Explanation note: Collection data for Museum specimens examined in the morphological comparisons. The specimens come from the herpetological collection of Centro de Ornitología y Biodiversidad (
Table S1
Data type: excel table
Explanation note: Uncorrected p-distances for the ND2 gene region between species of Hoplocercinae.