Research Article |
Corresponding author: Lourdes Y. Echevarría ( lourdese.20@gmail.com ) Academic editor: Alexander Haas
© 2021 Lourdes Y. Echevarría, Pablo J. Venegas, Luis A. García-Ayachi, Pedro M. Sales Nunes.
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:
Echevarría LY, Venegas PJ, García-Ayachi LA, Nunes PMS (2021) An elusive new species of gymnophthalmid lizard (Cercosaurinae, Selvasaura) from the Andes of northern Peru. Evolutionary Systematics 5(2): 177-187. https://doi.org/10.3897/evolsyst.5.68520
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We describe a new species of Selvasaura from the montane forests of the eastern slopes of the Andes in northern Peru, based on external and hemipenial morphological characters and previous phylogenetic analyses. The new species can be differentiated from the other two Selvasaura species in having keeled dorsal scales usually flanked by longitudinal striations, in adults and juveniles; adult males with a yellow vertebral stripe bordered by broad dark brown stripes on each side and a unilobed hemipenis surrounded by the branches of the sulcus spermaticus. The description of the new species contributes information about new states of diagnostic characters of Selvasaura and natural history.
Arboreality, Bromeliad, Gymnophthalmidae, Hemipenial morphology, Peruvian Yungas ecoregion, Taxonomy
The subfamily Cercosaurinae is the most diverse taxon of Gymnophthalmidae, currently containing 22 genera. In the last five years, several Cercosaurinae genera have been described or resurrected (e.g.,
A clade of microteiid lizards, including samples from Ecuador and Peru, was identified as not nested in any recognized Cercosaurinae genus by
Specimens were collected during four field surveys conducted between 2014 and 2020. Field surveys to Laurel and Fundo Alto Nieva, in San Martín department, were conducted during the wet season in November 2014 and January 2020, respectively. Surveys in Amazonas department, at Copal and Quebrada Gajmal, were conducted in June 2017 and October 2018 during the dry season and transition from dry to wet season, respectively. Anurans and reptiles were actively searched using the visual encounters (VES) method (
The following measurements were taken, to the nearest 0.1 mm, with a digital caliper: head length (HL), head width (HW), shank length (ShL), axilla-groin distance (AGD), and snout-vent length (SVL). Tail length (TL) was measured with a ruler and recorded to the nearest millimeter. Except for males with everted hemipenes, a short incision in the base of the tail was made to check for the presence of hemipenes. The volume of oviductal eggs was calculated in two gravid females (
Definitions of morphological characters follow
The left hemipenis of the holotype
We used MEGA (
We followed the evolutionary species concept (
The allocation of the new species in the genus Selvasaura is based on previously published phylogenetic evidence (
Uncorrected genetic distances among Selvasaura were 4.8–6.3% for 12S; 4.7–5.2% for 16S; 0.3–0.8% for c-mos; and 13–14% for ND4 (Appendix
Unnamed Clade 3 (
Selvasaura
sp. (
Selvasaura
sp. (
Peru • ♂, adult; San Martín Department, Mariscal Cáceres Province, Huicungo District, Laurel; 06°41'2"S, 77°41'44.3"W; 2,762 m; 02 Nov. 2014; L.Y. Echevarría, A.C. Barboza and J. Briones leg.;
Dorsal (A), lateral (B) and ventral (C) views of the head, and dorsal (D) and ventral (E) views of the body of Selvasaura evasa sp. nov. holotype,
Peru • 2 ♀ adults, 1 ♀ subadult, 2 juveniles, collected with the holotype;
A small gymnophthalmid (SVL 51.1–52.2 mm [n = 2] in females and 41.9–46.1 mm [n = 4] in males) characterized by: 1) body slender; 2) head pointed, 1.4 to 1.6 times longer than wide; 3) ear opening distinct, moderately recessed; 4) nasals separated by undivided frontonasal; 5) prefrontals, frontal, frontoparietals, parietals, postparietals and interparietal present; 6) parietals longer than wide; 7) three supraoculars; 8) superciliar series complete, consisting of four scales; 9) nasal completely or partially divided (behind the nostril); 10) loreal in contact with second supralabial; 11) supralabials usually seven; 12) two pairs of genials; 13) collar present, composed by 9–10 enlarged scales; 14) 33–38 transverse rows of dorsal scales; 15) 20–25 transverse rows of ventral scales; 16) 10–12 longitudinal rows of ventral scales; 17) 44–50 scales around midbody; 18) lateral scales at mid-body reduced or absent, present in a maximum of three rows; 19) limbs pentadactyl, all digits clawed; 20) subdigital lamellae under Finger IV 14–19, under Toe IV 17–24; 21) femoral pores 7–10 in females and 9–12 in males; 22) cloacal plate with four large scales; 23) tail 1.3–1.9 times longer than body; 24) caudals keeled dorsally and smooth ventrally; 25) lower palpebral disc undivided, pigmented or transparent; 26) dorsum brown with a yellow vertebral stripe, bordered by broad dark brown stripes in adult males; 27) cream labial stripe extending up to insertion of forelimb in males, females and juveniles; 28) sides of body brown and cream on ventrolateral region in males, females and juveniles; 29) well defined ocelli usually absent; adults and juveniles with a row of faint ocelli (black outline and cream center) followed by cream spots, usually up to midbody.
Selvasaura evasa sp. nov. can be distinguished from S. brava (character states in parentheses) by having 0–3 lateral rows of reduced scales at midbody (6–7); 9–12 femoral pores in males (7–9); keeled dorsal scales, usually flanked by longitudinal striae in adults and juveniles (slightly rugose in adults and slightly keeled in juveniles); ventral surface of tail orange in adult males (yellowish white); and a unilobed hemipenis (bilobed). Selvasaura evasa sp. nov. can be distinguished from S. sp. Ecuador (character states in parentheses) by having a larger size, SVL 41.9–46.1 mm, n = 3, in adult males (maximum SVL 39.7 mm); keeled dorsal scales, usually flanked by longitudinal striae (striated); 33–38 transverse rows of dorsal scales (25–32); 10–12 longitudinal rows of ventral scales at midbody (8–10); 9–10 scales on collar (7–9); a yellow vertebral stripe with broad dark brown stripes on each side in adult males (cream or gray with scattered black marks along sides).
Adult male (
Scales on nape wider than dorsals; scales on sides of neck small and granular; dorsal scales elongated, imbricate, arranged in transverse rows; scales on dorsal surface of neck striated; 33 dorsal scales between occipital scales and posterior margin of hind limbs; 21 dorsal scales rows in a transverse line at midbody; ventrolateral scales smooth; dorsals separated from ventrals by one (right) or two (left) rows of small scales at the level of the 10th transverse row of ventrals; lateral body fold present; ventrals smooth, longer than wide, arranged in 22 transverse rows between collar fold and preanals; 10 ventral scales in a transverse row at midbody; subcaudals smooth; limbs overlap when adpressed against midbody; axillary region composed of granular scales; scales on dorsal surface of forelimb striated, imbricate; scales on ventral surface of forelimb granular; three thick, smooth thenar scales; supradigitals (right/left): 3/3 on finger I, 7/7 on II, 9/9 on III, 11/11 on IV, 7/7 on V; supradigitals 4/4 on toe I, 6/6 on II, 10/10 on III, 12/11 on IV, 9/9 on V; subdigital lamellae on fingers divided proximally and single distally, 7/7 on finger I, 12/13 on II, 16/16 on III, 16/19 on IV, 12/13 on V; subdigital lamellae on toes divided proximally and single distally, 7/7 on toe I, 12/10 on II, 17/16 on III, 22/22 on IV, 15/15 on V; groin region with small, imbricate scales; scales on dorsal surface of hind limbs striated, imbricate; scales on ventral surface of hind limbs smooth, imbricate; scales on posterior surface of hind limbs granular; 10 femoral pores on each thigh; preanal pores absent; two anterior and four posterior cloacal plate scales.
Measurements and proportions of the holotype in mm: HL 10.6, HW 7.1, ShL 5.5, AGD 25.4; TL/SVL 1.9; HL/SVL 0.2; HW/SVL 0.2; ShL/SVL 0.1; AGD/SVL 0.6.
Dorsum brown with a broad yellow vertebral stripe bordered by a broad dark brown stripe on each side, and extending from interparietal to base of tail, where it becomes a light brown stripe. The vertebral stripe is continuous with a light brown stripe on the dorsal surface of the tail. Dorsal surface of head brown with pale yellow suffusion on frontoparietals and frontal. Lateral surface of head brown. Iris orange. Supralabials and infralabials cream with brown mottling. Cream labial stripe extending posteriorly up to insertion of forelimb. Flanks of body brown, ventrolateral region cream. A longitudinal row of small pale-yellow spots on dorsolateral region. Flanks with two faint ocelli followed by small cream spots, from forelimb insertion to base of tail. Dorsal surface of tail light brown with orange splotches on the sides. Dorsal surface of forelimbs and hind limbs brown; only fingers I and II and toes I and II yellow. Ventral surface of head cream with brown flecks. Ventral surfaces of neck, chest and belly cream with blurred brown splotches on each scale. Ventral surface of tail orange. Ventral surface of forelimbs and hind limbs yellow with brown flecks.
Similar to coloration in life. Suffusion on frontoparietals and frontal cream; ventral surface of forelimbs and hind limbs cream with brown spots; ventral surface of tail pale pink on anterior third and cream on the remainder.
Variations in scale counts and SVL of Selvasaura evasa sp. nov. and comparisons with congeners are presented in Table
Variation in scutellation and sexual dimorphism in SVL (mm) of Selvasaura evasa sp. nov. and its congeners, S. brava and S. sp. Ecuador.
Character | Selvasaura evasa sp. nov. (n = 7) | Selvasaura brava (n = 6) | Selvasaura sp. Ecuador (n = 3) |
---|---|---|---|
Scales in collar | 9–10 | 9–11 | 7–9 |
Transverse rows of dorsals | 33–38 | 33–36 | 25–32 |
Laterals at midbody | 0–2 | 6–7 | 5 |
Transverse rows of ventrals | 20–25 | 22–25 | 20–23 |
Longitudinal rows of ventrals | 10–12 | 10 | 8–10 |
Scales on cloacal plate | 4–5 | 4 | 4 |
Lamellae under Finger IV | 14–19 | 14–16 | 12–16 |
Lamellae under Toe IV | 17–24 | 18–22 | 18–20 |
Femoral pores in females (one leg) | 7–10 | 0 | unknown |
Femoral pores in males (one leg) | 9–12 | 7–9 | 9–12 |
Maximum SVL in females (mm) | 52.2 | 42.1 | unknown |
Maximum SVL in males (mm) | 46.1 | 45.9 | 39.7 |
Two juvenile (
All adult males have a similar coloration, only
Juvenile specimens
One to four faint ocelli (black outline and cream center) are present on the flanks of adult and juvenile specimens. These ocelli are usually followed by cream spots, except in
The left hemipenis of the holotype is completely everted and fully expanded, 5 mm long (~four subcaudals); organ unilobed, capitate, with lobe detached from body and bordered by the branches of the sulcus spermaticus; sulcus spermaticus broad and shallow throughout the hemipenial body, originating at the base of the hemipenis, central in position, and extending in a straight line until it divides into two branches at the half-length of the organ; sulcal branches separated by fleshy fold. Hemipenial body roughly Y-shaped with 15 pairs of transversal flounces, separated by a longitudinal nude area on asulcate face, except for the first five proximal-most flounces; all flounces ornamented with calcified spicules (Fig.
Selvasaura evasa sp. nov. is known from four localities along the eastern slopes of the Andean Cordillera Central, in Amazonas and San Martín departments, northern Peru, at elevations from 1,938 to 2,762 m (Fig.
Distribution map of Selvasaura. Symbols with a dot in the middle correspond to type localities.
The two adult females collected at Laurel were gravid, each with two eggs. Specimen
The specific epithet evasa is derived from the Latin adjective ēvāsa meaning scaped and refers to the evasive nature of this species. The first specimens of Selvasaura evasa sp. nov. were collected in 2014 despite continuous surveys, since 2003 in 20 localities along the montane forests of Amazonas and San Martín departments, it is only known from four localities.
The results of
The description of a new species of Selvasaura, contributes new states of diagnostic characters of the genus: dorsal scale relief, pigmentation of lower palpebral disc, and presence of femoral pores in females. Furthermore, although the unilobed hemipenes are described and illustrated to Selvasaura sp. Ecuador (
Additionally, the description of Selvasaura evasa sp. nov. contributes with natural history information for this recently discovered and poorly known Andean genus. It is reinforced that the arboreal habitat is still little explored in gymnophthalmids (
The new species of Selvasaura was discovered during fieldwork supported by: Critical Ecosystem Partnership Fund (CEPF) and Fondo de Promoción de las Áreas Naturales Protegidas del Perú (PROFONANPE) with the projects: Updating the status of an endemic harlequin frog from Peru (project number CEPF-108792) and Community forest conservation in the northeastern biodiversity corridor in Peru (project number CEPF-66127); APECO under the research grant “Carlos Ponce del Prado Award (XI edition)”; Global Genome Initiative (GGBN–GGI); and NGO´s Ucumari and Yunkawasi. Fieldwork would not have been possible without the logistic support of the following people: Marco Salas from Ucumari, Fanny M. Cornejo from Yunkawasi, Odile Sanchez from PROFONANPE, Mariela Leo and Glen Seitz from APECO. We are especially grateful with our field companions: LYE is indebted to Andy Barboza, Joaquín Briones, and Marco Salas; AGA is indebted to Jesús Ormeño; PJV is indebted to Juan C. Chávez. PJV is grateful to Rainforest Partnership for funding his herpetological research during 2021. PMSN is supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq (fellowship number 313622/2018-3). The authors are grateful to William W. Lamar for revising the English language of the manuscript. The authors are grateful to the Centrum für Naturkunde (CeNak) – Center of Natural History – University of Hamburg for supporting the publication of Evolutionary Systematics.
Specimens examined
Selvasaura sp. Ecuador – (n = 3) Ecuador: QCAZ 5073 & 12798 Napo, Wildsumaco Wildlife Sanctuary; QCAZ 9140 Pastaza, Zanjarajuno Ecological Center.
Uncorrected genetic distances for 12S, 16S, c-mos, and ND4 within Selvasaura.
12S | |||
---|---|---|---|
1 | 2 | 3 | |
1. Selvasaura brava MUSM 32738 | |||
2. Selvasaura evasa |
5.7 | ||
3. Selvasaura sp. Ecuador QCAZ 12798 | 4.8 | 5.7 | |
4. Selvasaura sp. QCAZ 12891 | 5.7 | 6.3 | 4.8 |
16S | |||
1. Selvasaura brava MUSM 32738 | |||
2. Selvasaura evasa |
4.7 | ||
3. Selvasaura sp. Ecuador QCAZ 12798 | 4.9 | 5.2 | |
4. Selvasaura sp. QCAZ 12891 | 5.2 | 5.2 | 4.7 |
c-mos | |||
1. Selvasaura brava MUSM 32738 | |||
2. Selvasaura evasa |
0.3 | ||
3. Selvasaura sp. Ecuador QCAZ 12798 | 0.5 | 0.8 | |
4. Selvasaura sp. QCAZ 12891 | 0.3 | 0.5 | 0.8 |
ND4 | |||
1. Selvasaura brava MUSM 32738 | |||
2. Selvasaura evasa |
– | ||
3. Selvasaura sp. Ecuador QCAZ 12798 | – | 13.7 | |
4. Selvasaura sp. QCAZ 12891 | – | 13.0 | 14.0 |