Gonatodes chucuri, Meneses-Pelayo & Ramírez, 2020

Meneses-Pelayo, Elson & Ramírez, Juan P., 2020, A new species of the genus Gonatodes (Squamata: Sauria: Sphaerodactylidae) from the western flank of the Cordillera Oriental in Colombia, with description of its hemipenial morphology, Zootaxa 4729 (2), pp. 207-227 : 211-216

Gonatodes chucuri sp. n.

[ urn:lsid:zoobank.org:pub:8BE725A2-BEA6-48CF-AFCE-B397A6F75608 ]

Proposed standard English name. Chucuri Gecko

Proposed standard Spanish name. Gecko del Chucurí

( Figs. 2 – 5 )

Holotype. UIS-R-3146 ( Fig. 2 ), an adult male collected by Elson Meneses-Pelayo on November 06, 2014 at Finca El Diviso , vereda La Colorada, municipality of San Vicente de Chucurí, department of Santander, Colombia (6°49’29.72”N, 73°28’34.57”W, ca. 1330 m).

Paratypes. Fifteen specimens collected by the first author (all from department of Santander, Colombia): One adult female (UIS-R-3005), 01 October 2014 ; one adult male (UIS-R-3057), 16 January 2015; one adult male and two adult females (UIS-R-3077-79, respectively), 28 February 2015; two adult females (UIS-R-3169-70), 13 July 2015, from the same locality of the holotype. Finca la Palmita , vereda Venceremos, municipality of Zapatoca (6°55’40.49”N, 73°21’10.94”W, ca. 890 m): two adult females (UIS-R-3535, UIS-R-3537), 05 June 2016 ; one adult male (UIS-R-3616), 09 September 2016; three adult females UIS-R-3715-17, 14 November 2016. Cerro de la Paz, vereda Altamira, municipality of Betulia (7°2’16.53”N, 73°24’41.42”W, ca. 790 m): one adult female (UIS-R-3381), 07 April 2016. Sector la Aguamieluda , vereda la Putana, municipality of Betulia (7°1’26.79”N, 73°26’54.86”W, ca. 745 m): one adult female (UIS-R-3447), 28 May 2016 .

Referred specimens. Seven juvenile specimens of undetermined sex collected by first author (all from department of Santander, Colombia): UIS-R-3135, 01 December 2014, with the same data as the holotype; Finca la Palmita , vereda Venceremos, municipality of Zapatoca (6°55’40.49”N, 73°21’10.94”W, ca. 890 m): UIS-R-3403, 23 April 2016 ; UIS-R-3418, 02 May 2016; UIS-R-3536, 05 June 2016; UIS-R-3613-15, 09 September 2016.

Diagnosis. Gonatodes chucuri is distinguished from all congeners by the following combination of characters: (1) moderate body size, males from 35.8 to 43.05 mm and females from 27.74 to 40.17 mm SVL; (2) elongated supraciliary spine absent, but with 2 or 3 small conical supraciliary scales; (3) absence of a cluster of distinctly enlarged conical scales on the sides; (4) 92 to 103 scales around midbody; (5) 38 to 45 ventral scales counted in a longitudinal row; (6) males with escutcheon area on belly and undersurface of thighs; (7) two lateral rows of scales on distal parts of fingers and toes; (8) ventral surface of tail with a pattern of scales consisting in a medial row of enlarged subcaudals in which there are larger scales in contact with three scales laterally, separated from each other by a single smaller scale which contacts two scales laterally (subcaudal pattern type C of Rivero-Blanco & Schargel (2012); (9) males and females with cryptic coloration pattern dorsally, and yellow to ocher ventrally, without sexual dichromatism.

Gonatodes chucuri and G. lichenosus from Sierra de Perijá, Venezuela ( Rojas-Runjaic et al. 2010) are the only mainland species of Gonatodes in which there is not sexual dichromatism. However, G. chucuri differs from this species (characters of G. lichenosus in parentheses) in not having clusters of enlarged conical to spinelike scales along the body (spinelike scales present), in commonly having a subcaudal pattern 1’1” with no changes along the tail (subcaudal pattern 1’2” basally, that changes to 1’1” distally), as well as by the presence of 13–17 (4-5) lamellae under fourth finger (14–16 (4-5)) and 15–20 (5-7) under fourth toe (18–19 (7)). Gonatodes chucuri presents a subcaudal pattern type C (1’1”), which it is also found in G. alexandermendesi Cole & Kok , G. eladioi do Nascimento, Avila-Pires & da Cunha, G. infernalis Rivas & Schargel, G. superciliaris Barrio-Amorós & Brewer-Carias , G. naufragus , and G. timidus Kok. However , the new species differs from G. alexandermendesi and G. superciliaris in lacking an elongated supraciliary spine (a single elongated spine is present). Gonatodes chucuri differs from G. eladioi in reaching SVL of 43.05 mm (<40 mm in G. eladioi ) and by the absence of a light vertebral band in males (present). Gonatodes chucuri is smaller than G. infernalis (SVL> 55 mm), and usually has two lateral scales on fingers and toes (usually four). Gonatodes chucuri is larger than G. naufragus (SVL <27.2 mm) and smaller than G. timidus (adult reaching nearly 51.6 in SVL). The new species is found sympatrically with the widespread G. albogularis in several localities below 1000 m, but is distinguished by not having sexual dichromatism (sexual dichromatism present, with males showing bright and conspicuous colors, and females showing cryptic color patterns) and by presenting a subcaudal pattern 1’1” or 1’2” basally, that changes to 1’1” distally (a subcaudal pattern 1’1’1”).

Description of the holotype. An adult male ( Fig. 2 ), with SVL of 43.05 mm. Head 1.3 times longer than wide (HL: 11.35 mm; HW: 8.38 mm). Snout subacuminate in dorsal view, rounded in profile, gently sloping toward top of head ( Figs. 2 a–b). Neck slightly narrower than head and body. Body wider than high, nearly cylindrical; axilla- groin distance 18.25 mm. Limbs and digits well developed; fourth toe length 5.81 mm. Tail complete (with its distal half regenerated), round in cross section, tapering towards tip, 1.04 times SVL (TL: 45.03 mm). Rostral large, subpentagonal, visible from above, with a median cleft extending forward from posterior margin to near midpoint of the scale. Postrostrals five, lateral ones (supranasals) distinctly larger than the medials, situated above the nasals, and medially separated by two posterior medials; medials postrostrals similar in size to adjacent posterior scales on snout, in contact with the posterior rostral margin. Nostril bordered by the rostral, a lateral postrostral and three postnasals; not in contact with first supralabial. Postnasals similar in size to adjacent loreals. Scales on snout and loreal region nearly round to nearly conical, juxtaposed. Loreal scales 8/7 (left/right) in a straight line between postnasal and anterior margin of the orbit and in contact with the supralabials. Scales decrease slightly in size from the postrostrals to the posterior part of head. Scales on supraorbital region similar (in size and shape) to, and continuous with those on top of head. Supraciliary flap without an elongate supraciliary spine, but 2/3 (left/right) conical supraciliary scales, somewhat larger and projecting posterolaterally on anterior half of row. Pupil round. Supralabials 6/6 (left/right), first largest, second through third or fourth roughly subequal, fifth and sixth smaller, fifth scale below center of eye in both sides. Scales on temporal region similar to those on posterior upper part of head. Ear opening (0.96 mm) much smaller than eye (1.95 mm), vertically oval. Mental large, with round anterior margin following lower lip, posterior margin cuadrangular. Two postmentals, distinctly larger than adjacent posterior scales ( Fig. 2c ). Scales on chin small and polygonal located directly behind postmentals, granular and tiny posteriorly; a few series of larger, polygonal, juxtaposed scales adjacent to infralabials. Infralabials five (both sides), decreasing in size posteriorly, first two very large and projecting onto chin, a quarter below the center of eye. Scales on nape and on sides of neck granular, continuous with those on head and body. Scales on throat smooth, imbricate, with round posterior margin, with a short transitional area of granular scales on chin and gular area. Dorsals granular, on vertebral area similar in size to scales on snout but larger to the top of head; slightly larger in the dorsolateral region and on the flanks. Transition between scales on flanks and ventrals somewhat abrupt but not clearly demarcated. Ventral region with scales distinctly larger than dorsals, slightly smaller on chest than on belly, smooth, nearly hexagonal, with round posterior margin, imbricate, in oblique rows, also forming rather regular longitudinal rows on belly; with 44 scales along the midventral line between anterior margin of forelimbs and vent. Scales around midbody about 98, of which 20 are ventrals. Preanal scales at margin of vent much smaller than ventrals on belly. Escutcheon area present on posterior abdomen and on undersurface of thighs ( Fig. 4a ), composed of a cluster of 50 escutcheon scales on posterior portion of belly and a preanal plate between thighs; clusters of 36/34 (right/left) escutcheon scales arranged in four transverse rows on ventral surface of thighs. Scales on dorsum of tail becoming flat, smooth, rounded and imbricate, posterior to level of vent. Scales on underside of tail smooth, flat, imbricate, increasing in size towards the midventral line; first five small subcaudals posterior to vent on midventral row increasing in size posteriorly but not clearly differentiated from adjacent laterals, followed by a midventral row of transversely enlarged scales. First enlarged subcaudals arranged in one series consisting in a medial row of enlarged subcaudals in which there are larger scales in contact with three scales laterally, separated from each other by a single smaller scale which contacts two scales laterally (1’1”) ( Fig. 4b ). Scales on limbs smooth, flat, roundish, imbricate on anterior and ventral surfaces; granular and juxtaposed on dorsal and posterior surfaces. Lamellae under first (I) through fifth (V) finger (infraproximals in parentheses): I: 13/12(4/3), II: 13/13(4/4), III: 15/15(4/4), IV: 14/14(4/4), and V: 15/15(5/5), respectively. Lamellae under first through fifth toe (infraproximals in parentheses): I: 12/11(4/3), II: 14/13(5/4), III: 17/16(5/4), IV: 19/19(7/7), and V: 18/0(5/5), respectively. Infraproximal scales on fingers and toes enlarged and swollen ( Figs. 4 c–d). Fingers and toes with two lateral rows of scales distally. Claws exposed, non-retractile, between two basal scales (dorsal and ventral) ( Fig. 2 ).

Color in life. The dorsal surface of the head (snout, eyelids, interorbital and temporal areas, top of the head and nape) is yellowish gray, irregularly speckled with blackish brown. The loreal region has a blackish brown loreal stripe extending from the nostril to the anterior margin of eye. Two blackish chestnut postocular stripes, extend posteriorly from the orbital margin and expand posteriorly; the upper one is sinuous and extends to the neck, with its end pointing medially and near the end of the opposite stripe; the lower stripe extends towards the neck and blends with the background color of the shoulder. Rostral, supralabial, mental and infralabial scales have blackish brown vertical stripes alternating with narrow yellowish lines. A dirty gray vertebral stripe extends from the neck (continuing with the gray dorsal area of the head) to the dorsal region of vent. This vertebral stripe is wide, irregularly and diffusely delimited by light brown, with six transversal extensions between neck and pelvis. The flanks are light brown with some irregular bands light brown of one or two scales wide. The limbs are light brown, with wide black- ish brown irregular spots. The ventral surfaces are ochre yellow, finely speckled with pale brown on chin, throat and lateral borders of chest and belly; with some faint pale brown longitudinal stripe at the throat. The undersurface of limbs is dirty yellow, the palms and soles are gray; the escutcheon scales on the belly and thighs are pale yellow, most with the distal border finely delineated with pale brown. The tail is blackish chestnut laterally and dirty yellow to pale yellow ventrally. The iris is yellowish orange, with a thin golden ring around the pupil. The claws are white ( Figs. 3 , 4 ).

Color in preservative. The dorsum of the head, vertebral stripe and the background pattern of limbs are dark brown; the blackish brown and blackish chestnut colors of the loreal, postoculars, labial, and limbs stripes, flanks and tail become pale gray. The irregular light brown bands in the flanks turn into white; the palms and soles are pale gray with black spots in the scales. The chin, throat, chest, belly, and undersurface of the limbs are dirty white finely speckled with pale brown; the escutcheon scales (belly and thighs) is cream color with its distal border finely demarcated with brown.

Variation in paratypes (n=15). The largest male is the holotype measuring 43.05 mm in SVL, 44.74 TL; UIS- R-3169 is the largest female measuring 40.17 in SVL. Supralabials 6 (n = 12) or 5 (n = 3) to the level of the center of the eye, followed posteriorly by 1–2 small polygonal scales, and subsequently by multiple tiny granular scales to the rictus of the mouth; Infralabials 5 (n = 9) or 4 (n = 6) to the level of the center of eye, followed posteriorly by 1–2 small polygonal scales and subsequently by multiple tiny granular scales. Postrostrals 7 (n = 2), 6 (n = 3), 5 (n = 9) or 3 (n = 1). Small scales in contact to rostral medially 1 (n = 10), 2 (n = 3) or 3 (n = 2). Postnasals 2 (n = 1), 3 (n = 13) or 4 (n = 1). Loreal scales 7 (n = 8), 8 (n = 3) or 9 (n = 4). Postmentals 2 (n = 15). Scales around the midbody are 92–103, of which about 16–20 are ventrals. There are 38–45 ventral scales along a midventral line from the anterior margin of forelimbs to the anterior margin of hind limbs. Lamellae under second (II) through fourth (IV) fingers (infraproximal lamellae in parentheses): II: 12–14 (4), III: 14–16 (4) and IV: 13–17 (4–5). Lamellae under second through fourth toes (infraproximal lamellae in parentheses): II: 13–14 (4), III: 15–18 (4–5) and IV: 15–20 (5–7). Fingers and toes always with two lateral rows of scales distally. Subcaudal scale pattern composed of 1’1” with no changes along the tail (n = 8) or subcaudal pattern 1’2” basally, that changes to 1’1” distally (n=5), the character state for the remaining two specimens is unknown as they lost their tails.

Hemipenial morphology (n = 3). Hemipenis slightly bilobed; 6 mm in length; trunk becoming distinctly wider distally; lobules short and rounded and not capitated. The sulcus spermaticus originates in the lateral face of the organ with wide lateral folds forming a narrow channel to the bifurcation; it runs diagonally along the sulcate face of the body and bifurcates perpendicularly almost to the apex of the lobes, marking a broad groove up to the most distal and posterior area of the lobes. In sulcate view, basally the hemipenis does not present calices or spicules, it is smooth and without ornamentations. Laterally, the hemipenial body is smooth at the base, has two globular protrusions or protuberances at the base of the lobes, and it is oriented vertically and slightly outward. The lobes are compact, truncated, and rounded, covered by small spines of the same size that surround the branches of the spermatic sulcus; in asulcate view, the spines gradually diminish in size up to the middle of the lobe, where a large calyculate area begins in the form of an inverted triangle down to the middle of the body of the hemipenis. In the zenith view, the lobes and the small spines are organized in M-shape and an irregular fold protrudes between the lobes ( Fig. 5 ).

Etymology. The specific epithet, chucuri , is used as a noun in apposition and refers to the Chucurí river basin in the municipality of San Vicente de Chucurí, where the type locality of Gonatodes chucuri is located.

Distribution and natural history. Gonatodes chucuri occurs in the western foothills of the Andean Cordillera Oriental in the department of Santander, Colombia, between 500-1200 m in elevation. The known distributional area of G. chucuri is relatively small, approximately 584 km 2 ( Fig. 6 ), and all records are from low montane forest.

Gonatodes chucuri was the most uncommon species of sphaerodactylid lizard found during surveys conducted by the Grupo de Estudios en Anfibios y Reptiles de Santander of the Universidad Industrial de Santander during 2014, 2015, and 2016 at several localities in the Middle Magdalena Valley and foothills of the Serranía de los Yariguíes National Park. Specimens were collected in both primary and secondary forests, cultivated areas of cocoa and coffee with native vegetation, as well in an ancient house having stone and mud walls ( Fig. 7A, B, D ). Almost all specimens were found active during the day below the bark of the trees of Moraceae and Fabaceae , between 0.2 and 5.5 m above the ground ( Fig. 7C, E, F ). Observations made during the collections suggest that G. chucuri is a diurnal species, but that most of the time it stays hidden under bark. More than 10 individuals have been found coexisting in the same tree, and communal nests with approximately 20 eggs have been found under the bark and small cracks of trees and termite mounds ( Fig. 7C ). Even though G. chucuri has been found in areas with crops, individuals were only found in large trees at the edges, next to areas of forest and scrub vegetation, suggesting that the species is sensitive to losses of tree and native vegetation cover.

Figures

FIGURE 2. Dorsal and ventral view of Gonatodes chucuri sp. nov. (A, B); detail of posterior and anterior limbs (C); ventral view showing escutcheon areas on posterior part of belly and undersurface of thighs (D); detail of head in lateral, dorsal and ventral view (E); (UIS-R- 3146, holotype, adult male, SVL 43.05 mm).

FIGURE 3. Gonatodes chucuri sp. nov. (UIS-R-3616, male; UIS-R-3716 female) paratypes, adult male in life, SVL 46.9 mm). Photo: José Vieira (male dorsolateral view) and Elson Meneses-Pelayo (female and remaining photographs).

FIGURE 4. Gonatodes chucuri sp. nov. (UIS-R-3615, juvenile). Dorsal and ventral view.

FIGURE 5. Hemipenial morphology of Gonatodes chucuri sp. nov. (UIS-R-3077). (Right) Asulcate view; (Center) Sulcate view; (left) overhead view, scale bar = 1 mm.

FIGURE 6. Geographic distribution of Gonatodes chucuri sp. nov. Finca El Diviso, San Vicente de Chucurí municipality, type locality (star); paratype localities (red circles); Embalse Topocoro (blue polygon); Northern region of the Serranía de los Yariguíes National Park (green polygon with black border).

FIGURE 7. Landscape views of the type locality of Gonatodes chucuri along the Vereda La Colorada, municipality of San Vicente de Chucurí, department of Santander, Colombia (A, C, D, E, F). General landscape (A), anthropogenic environment found in the paratype locality on Vereda Venceremos, Zapatoca, Finca La Palmita (B), oviposition site (C), habitat within cocoa crops (D), microhabitats under the bark of trees (E, F).