A new non-sexually dichromatic species of the genus Gonatodes from Sierra de Perijá, Venezuela

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Zootaxa 2671: 1–16 (2010) www.mapress.com / zootaxa/

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Copyright © 2010 · Magnolia Press

ZOOTAXA ISSN 1175-5334 (online edition)

A new non-sexually dichromatic species of the genus Gonatodes (Sauria: Sphaerodactylidae) from Sierra de Perijá, Venezuela FERNANDO J. M. ROJAS-RUNJAIC1,3, EDWIN E. INFANTE-RIVERO2, PEDRO CABELLO1 & PABLO VELOZO2 1

Museo de Historia Natural La Salle. Apartado Postal 1930, Caracas 1010-A, Venezuela Museo de Biología, La Universidad del Zulia, Facultad Experimental de Ciencias, Apartado Postal 526, Maracaibo 4011, Venezuela 3 Corresponding author. E-mail: rojas_runjaic@yahoo.com

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Abstract A new species of diurnal gecko of the genus Gonatodes is described from Sierra de Perijá in western Venezuela. The new species is the only member of the genus lacking sexual dichromatism, and can be readily distinguished from all congeners by the unique combination of the following characters: medium body size; supraciliary spine absent; dorsolateral light spots coinciding with clusters of enlarged, conical to spinelike scales; males with escutcheon area on belly and undersurface of thighs; unique subcaudal scale pattern (1’2” followed by 1’1”); and both sexes with cryptic dorsal color pattern. The new species increases the number of Gonatodes known from Venezuela to 17. Key words: Gonatodes, Sphaerodactylidae, Andes, Perijá, Zulia, Venezuela

Resumen Se describe una nueva especie de gecko diurno del género Gonatodes con base en ejemplares provenientes de la Sierra de Perijá en el occidente de Venezuela. La nueva especie es la única del género que no exhibe dicromatismo sexual, y puede ser diferenciada fácilmente de sus congéneres por la combinación única de los siguientes caracteres: tamaño corporal mediano; espina supraciliar ausente; manchas claras dorsolaterales coincidentes con grupos de escamas agrandadas y cónicas a espiniformes; machos con área de escudo en el vientre y superficie ventral de los muslos; patrón único de escamas subcaudales (1’2” seguido de 1’1”); y ambos sexos con patrón de coloración dorsal críptico. Con esta nueva especie el número de Gonatodes en Venezuela asciende a 17.

Introduction The Neotropical genus Gonatodes Fitzinger is composed mainly of diurnal, relatively small lizards, with round pupils [the only exception being the nocturnal species G. antillensis (Lidth de Jeude)], and strong sexual dichromatism, such that males are usually conspicuously ornamented with bright colors whereas females are cryptically colored. This genus contains 23 currently recognized species (Barrio-Amorós & Brewer-Carías 2008, Cole & Kok 2006, Esqueda 2004, Powell & Henderson 2005, Rivas & Schargel 2008, Rivero-Blanco 1979, Schargel et al. 2010), distributed from Central America to central South America, and on many Caribbean islands (Avila-Pires 1995, Powell & Henderson 2005, Rivero-Blanco 1979). Venezuela harbors the highest species richness, with 16 species of Gonatodes (Barrio-Amorós & Brewer-Carías 2008, Esqueda 2004, Rivas & Schargel 2008, Schargel et al. 2010), seven of which are endemic to this country. Additionally, at least four other new species have been mentioned but remain undescribed (Rivero-Blanco 1979, Viloria & Calchi 1993). The Sierra de Perijá is the northernmost spur of the Andean range, and forms a natural boundary between Venezuela and Colombia. This region historically has been little explored and its fauna is still poorly known. Accepted by A. Bauer: 18 Oct. 2010; published: 9 Nov. 2010

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Since 2005 the staff of the Museo de Historia Natural La Salle and the Museo de Biología de La Universidad del Zulia have systematically inventoried the herpetofauna of the Venezuelan versant of Perijá, which has significantly increased the number of amphibians and reptiles known from this region (Barrio-Amorós et al. 2007, 2010, Infante et al. 2006a, 2006b, Infante-Rivero et al. 2008, 2009, Rojas-Runjaic & Infante 2006, 2008, Rojas-Runjaic et al. 2007, 2010). Currently 24 lizard species are known to occur on the Venezuelan versant of Perijá (Rojas-Runjaic & Infante-Rivero, unpublished data), four of which are in the genus Gonatodes: G. albogularis (Duméril & Bibron), G. petersi Donoso-Barros, G. vittatus (Lichtenstein), and G. sp. (Viloria & Calchi 1993). The last is likely an undescribed species but additional specimens are needed to clarify its status. During an expedition to the valley of Manastara in March 2009, as part of the ongoing surveys of the herpetofauna of Perijá, several specimens of a new species of Gonatodes were found. The new species differs from all other species of Gonatodes in not showing sexual dichromatism, with both sexes showing the same cryptic dorsal color pattern. Additionally, the subcaudal scale pattern is also different from that exhibited by all other congeners. We herein describe this new species, which increases to 17 the number of Gonatodes from Venezuela.

Material and methods Specimens examined are deposited in the Museo de Historia Natural La Salle, Caracas (MHNLS), and are listed in the appendix 1. Comparisons were taken from Avila-Pires (1995), Barrio-Amorós & Brewer-Carías (2008), Cole & Kok (2006), Rivero-Blanco (1979), and Rojas-Runjaic & Infante (2009). Description and terminology for morphological characters follows, in part, Rivero-Blanco (1979) and Avila-Pires (1995). Counts of infraproximal and infradistal scales were taken from all digits following Rivas & Schargel (2008). Gender was determined by examination of sexual characters like presence/absence of hemipenis (everted in two males), and escutcheon scales (present in all males). Additionally in all adult females a well-developed oviductal egg was noticeable through the skin. The formula for the ventral scales of the tail also follows AvilaPires (1995). The number of scales around midbody was counted on a line at the midpoint between the axilla and groin. All measurements were taken with digital calipers to the nearest 0.1 mm. Abreviations used are: SVL: Snout-Vent Length, from tip of snout to vent; TL: Tail Length, from posterior border of vent to tip of tail; HL: Head Length, from tip of snout to anterior margin of tympanum; HW: Head Width, taken at widest point of the head (between ear opening and angle of jaws); EYN: Eye-Nostril Distance, from nostril to anterior margin of eye; AXG: Axilla-Groin Distance.

Results Gonatodes lichenosus, sp. nov. Perijá Lichen-Gecko, Tuqueque Liquenoso de Perijá (Figs. 1–5) Holotype. An adult male, MHNLS 19116 (field number SP191), from Manastara, Yukpa indigenous community, Río Negro basin, Parque Nacional Sierra de Perijá, Municipio Machiques de Perijá, Sierra de Perijá, Estado Zulia, Venezuela (10°02’52.0”N, 72°48’42.8”W; elevation 1132 m asl), collected on 18 March 2009, by Fernando J. M. Rojas-Runjaic, Pedro Cabello, and Pablo Velozo. Paratypes. Three adult males (MHNLS 19101, 19109 and 19110), and two adult females (MHNLS 19107, 19111), same data as the holotype, collected between 16 to 18 March 2009. Referred specimens (not paratypes): An adult female (MHNLS 19108), and a juvenile (MHNLS 19117), with the same data as the holotype, collected between 16 and 18 March 2009; a neonate (MHNLS 19160), with the same data as the holotype, collected (as an egg) on 20 March 2009, and hatched in captivity on 24 April 2009.

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FIGURE 1. Gonatodes lichenosus sp. nov.: a. Male holotype (MHNLS 19116); b. Female paratype (MHNLS 19107).

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FIGURE 2. Details of dorsal (a), lateral (b), and ventral (c) views of the head of Gonatodes lichenosus sp. nov. (male holotype, MHNLS 19116). Scale bar represents 2 mm.

FIGURE 3. Dorsal view of Gonatodes lichenosus sp. nov. (male holotype MHNLS 19116), showing clusters of enlarged, conical to spinelike scales on the flanks of neck and trunk. White arrows indicate the clusters of scales magnified in upper right and lower left frames.

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FIGURE 4. Gonatodes lichenosus sp. nov. (male holotype, MHNLS 19116): a. Ventral view showing escutcheon areas on posterior part of belly and undersurface of thighs; b. Detail of subcaudal scale pattern; c. Ventral view of left hand (scale bar represent 1 mm); d. Ventral view of left foot (scale bar represents 2 mm).

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FIGURE 5. Variation on dorsal (a) and ventral (b) color pattern of the type series of Gonatodes lichenosus sp. nov.; a: from left to right, female paratypes MHNLS 19107 and 19111, and male paratypes MHNLS 19109 and 19110; b: from left to right, female paratypes MHNLS 19107 and 19111, and male paratypes MHNLS 19110 and 19109. Note the absence of sexual dichromatism in both views.

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Diagnosis. The new species can be readily distinguished from all congeners by the combination of the following characters: (1) body size moderate, with males from 39.05 to 41.4 mm, and females from 40.65 to 44.45 mm; (2) supraciliary spine absent; (3) dorsolateral light spots that coincide with clusters of enlarged, conical to spinelike scales; (4) 100 to 106 scales around midbody; (5) 42 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 of two to four basal series of single midventral scales in contact posterolaterally on each side with one scale followed by a divided midventral scale in contact with two scales per side (1’2”), and continuing distally with repetitive series of single midventral scale in contact posterolaterally with one scale per side and single midventral in contact with two scales per side (1’1”); (9) males and females with cryptic coloration pattern dorsally, and yellow to ocher ventrally, without sexual dichromatism. Gonatodes lichenosus, together with G. alexandermendesi Cole & Kok from Guyana and southeastern Venezuela (Cole & Kok 2006, Schargel et al. 2010), G. hasemani Griffin from south of the Amazonas River (Avila-Pires 1995), and G. superciliaris Barrio-Amorós & Brewer-Carías from Sima Mayor of Sarisariñama tepui, southern Venezuela (Barrio-Amorós & Brewer-Carías 2008), are the only species of Gonatodes in which clusters of enlarged conical to spinelike scales along the body are present (data from Avila-Pires 1995, Barrio-Amorós & Brewer-Carías 2008, Cole & Kok 2006, Rivero-Blanco 1979). However, Gonatodes lichenosus differs from these species (characters in parenthesis) in not having an elongate supraciliary spine (supraciliary spine present), having a subcaudal pattern 1’2” basally, that changes to 1’1” distally (medial subcaudal scales not distinctly differentiated from adjacent scales in G. hasemani; and, 1’1” pattern in G. alexandermendesi and G. superciliaris), and not having sexual dichromatism (sexual dichromatism present, with males showing bright and conspicuous colors, and females showing cryptic color patterns). Only one other species of Gonatodes, from La Azulita (Estado Mérida, Venezuela) and until now undescribed (Rivero-Blanco 1979) exhibits poorly defined sexual dichromatism; nevertheless there are some some evident color differences between sexes in this species, like the “golden appearance on the body” and the “flat gray gular region” in males. Gonatodes lichenosus differs from this undescribed species (characters in parenthesis) in not having any sexually dichromatic character (sexual dichromatism poorly defined but present as above mentioned), by the subcaudal pattern (subcaudal pattern 1’1’1”), and in having only two lateral rows of scales on distal the parts of fingers and toes (three lateral rows of scales on fingers and toes). Three other species of Gonatodes are known from Sierra de Perijá: G. albogularis, G. vittatus and G. petersi; the former two species inhabit the foothills up to 400 m, whereas the later is widely distributed on the eastern slope of Perijá from 200 to 1200 m (Rojas-Runjaic & Infante 2009) and is likely sympatric with the new species. These three species, unlike G. lichenosus, have a subcaudal pattern of 1’1’2” (G. albogularis) or 1’1’1” (G. vittatus and G. petersi), and show very marked sexual dichromatism, with males exhibiting a very conspicuous light vertebral stripe (G. vittatus and G. petersi) or a yellow to orange head with a blue blotch on the cheeks (G. albogularis). Description of holotype. An adult male (Fig. 1), with SVL of 40.0 mm. Head 1.1 times longer than wide (HL: 10.1 mm; HW: 9.0 mm). Snout 3.6 mm long, subacuminate in dorsal view, rounded in profile, gently sloping toward top of head (Figs. 2a–b). Neck slightly narrower than head and body. Body wider than high, nearly cylindrical; axilla-groin distance 17.4 mm. Limbs and digits well developed; fourth toe length 4.9 mm, 0.66 times shank length (7.4 mm). Tail complete (with distal quarter regenerated), round in cross section, tapering toward tip, 1.2 times SVL (TL: 48.9 mm). Tongue relatively wide, slightly narrowing anteriorly, tip rounded with a short median cleft, covered by scalelike papillae, which become smaller posteriorly. Teeth small, conical, subequal in length. Rostral large, subpentagonal, visible from above, with a median cleft extending forward from posterior margin to near midpoint of the scale. Postrostrals three, lateral ones (supranasals) distinctly larger than medial, situated above the nasals, and medially in contact by projections of their medial anterior margins; medial postrostral similar in size to adjacent posterior scales on snout, separate from posterior margin of rostral by lateral postrostrals. Nostril bordered by rostral, lateral postrostral and three postnasals; not in contact with first supralabial. Postnasals much larger than adjacent loreals. Scales on snout and loreal region nearly round to

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nearly conical, juxtaposed. Loreal scales about 8 (both sides) in a straight line between postnasals and anterior margin of orbit. Scales decrease slightly in size from postrostrals to 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 two (both sides) conical supraciliary scales, somewhat larger and projecting posterolaterally on anterior half of row. Pupil round. Supralabials 4/5 (left/right), first largest, second through third or fourth roughly subequal, fourth scale below center of eye in right side, and the third on left side. Scales on temporal region similar to those on posterior upper part of head. Ear opening (0.6 mm) much smaller than eye (1.9 mm), vertically oval. Mental large, with round anterior margin following lower lip, posterior margin roughly round. Postmentals two, 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, third below 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 short transitional area of granular scales on chin and gular area. Dorsals granular, on vertebral area similar in size to scales on snout and top of head; slightly larger dorsolaterally and on flanks. Several clusters of enlarged conical to spiniform scales on flanks of the neck and trunk, coinciding with small light spots (Fig. 3); 4/3 clusters on neck composed of 1 to 6 scales, and 6/7 on flanks of the trunk composed of 6 to 17 scales. 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 42 scales along the midventral line between anterior margin of forelimbs and vent. Scales around midbody about 104, of which 16 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 62 escutcheon scales on posterior portion of belly and preanal plate between thighs; clusters of 30/31 (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 (rather than conical), posterior to level of vent. Scales on underside of tail smooth, flat, imbricate, increasing in size toward 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 tranversely enlarged scales. First enlarged subcaudals arranged in two series of one single median scale in contact posterolaterally with one smaller scale, followed by a divided median scale in contact posterolaterally with two smaller scales (1’2”), and continuing posteriorly with a sequence of single median scales in contact posterolaterally with one or two smaller scales in an alternating fashion (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: 10/10(3/3), II: 12/12(4/4), III: 14/14(4/4), IV: 14/14(4/4), and V: 13/13(4/4), respectively. Lamellae under first through fifth toe (infraproximals in parentheses): I: 10/10(3/3), II: 12/12(4/4), III: 16/ 16(5/5), IV: 18/18(7/7), and V: 16/17(5/5), respectively. Infraproximal scales on fingers and toes enlarged and swollen (Figs. 4c–d). Fingers and toes with two lateral rows of scales distally. Claws exposed, non-retractile, between two basal scales (dorsal and ventral). Color in life. (Fig. 1) The dorsal surface of the head (snout, eyelids, interorbital and temporal areas, top of the head and nape) greenish 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 extend to the neck, with the 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

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infralabial scales have blackish brown vertical stripes alternating with narrow yellowish lines. A dirty beige vertebral stripe extends from the neck (continuing with the greenish gray dorsal area of the head) to near tail tip. This vertebral stripe is wide, irregularly and finely margined by blackish brown, with nine transversal dilatations between neck and pelvis, and three others on the tail. The flanks are blackish chestnut with several pale yellow flecks laterally aligned or in contact with the transversal dilatations of the vertebral stripe; these pale yellow flecks correspond with clusters of enlarged, conical to spiniform scales. The limbs are dirty gray, with wide blackish brown crossbands. The ventral surfaces are ocher yellow, finely speckled with pale brown on chin, throat and lateral borders of chest and belly; with a faint pale brown longitudinal stripe at each side of the throat. The undersurface of limbs are dirty yellow, the palms and soles are dirty 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 dorsal scales of tail have a pink iridescence. The iris is brownish orange, with a thin golden ring around the pupil. The tongue is white with pale gray dots anterolaterally. The claws are white. Color in preservative (after one year). The dorsum of the head, vertebral stripe and the background pattern of limbs are pale gray; the blackish brown and blackish chestnut colors of the loreal, postoculars, labial, and limbs stripes, flanks and tail have become pale brown; the pale yellow flecks that correspond with the clusters of enlarged scales have turned white; the palms and soles are pale gray; the chin, throat, chest, belly, and undersurface of the limbs are dirty white finely speckled with pale brown; in the escutcheon scales (belly and thighs) the white color is more intense and the finely delineate brown distal border is still distinct. Variation in paratypes. The three adult males range in SVL from 39.05 to 41.4 mm (40.31 ± 1.0), and the two adult females range from 40.65 to 44.45 mm (42.55 ± 2.7). Supralabial counts vary from 4 to 6, and infralabial counts from 5 to 6. Loreal scales counted in straight line between postnasals and anterior border of orbit range from 7 to 9. Male MHNLS 19110 and females MHNLS 19107 and 19111, have three postrostrals in contact with rostral, whereas males MHNLS 19101 and 19109 have only two (supranasals) in contact with rostral, as in the holotype. Postmental scales range from two (MHNLS 19107, 19109) to four (MHNLS 19101). Flanks of neck and trunk with 10 to 24 (on each side), clusters of 1 to 17 enlarged, conical to spinelike scales, present in males and females but more conspicuous on males. Scales around the midbody range from 100 to 106, of which 14 to16 are ventrals. Ventral scales 43 to 45 along trunk. Escutcheon area on belly composed of 68 and 70 scales on males MHNLS 19109 and 19110 respectively, only 29 and less conspicuous in male MHNLS 19101, absent in females. Escutcheon scales on undersurface of thighs 18 to 30, only present in males. Subcaudal scale pattern composed of 1 (MHNLS 19110) to 4 (MHNLS 19107, MHNLS 19111) 1’2” series occupying shorter basal portion of tail, followed by numerous 1’1” series extending to rest of tail. In MHNLS 19101 and MHNLS 19111, the 1’1” series not present as tail is regenerated. Regenerated portion of tail with subcaudal pattern that differs significantly from original tail; midventral scales form single row of wide, but very short plates (longest side transverse to longitudinal axis of tail), each extending laterally to ventrolateral surface of tail, and in contact laterally with small scales that look just like those on original tail. Variation in number of lamellae under first through fifth fingers: I: 9–10(2–3), II: 11–13(3–4), III: 13–15(4), IV: 14–16(4–5), and V: 13–14(4–5). Variation in number of lamellae under first through fifth toe: I: 10(2–3), II: 12–13(4), III: 15–17(4–5), IV: 18–19(7), and V: 16–18(5). Morphometric variation of type series is presented on Table 1. The coloration of the paratypes (based on photos in life) is like the holotype with only minor variations in dorsal color pattern and the ventral color of the tail (Figs. 5a–b). The dorsal surface of the head is more greenish and profusely speckled with blackish brown in the male MHNLS 19109. The specimens MHNLS 19107 (Fig. 1b), 19110 and 19111, have small white spots on the light background area, between the upper and lower postocular stripes (these spots correspond with clusters of enlarged conical to spinelike scales). The vertebral stripe is wider on the female MHNLS 19111 and male MHNLS 19110; much more irregularly bordered in the last one. In the regenerated portion of the tail (MHNLS 19109, 19111) the vertebral stripe is lost, and instead there is a dorsal pattern of irregular dark spots on a pale beige background. The blackish brown border of the vertebral stripe is wider and more conspicuous in MHNLS 19111 and 19109. The female

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MHNLS 19107 (Figs. 1b, 5a) has a lighter background color, the cephalic spot, loreal, labial and postocular stripes, border of the dorsal stripe, and the lateral spots of the flanks are light brown to brownish orange. In all paratypes the background color of the flanks of the trunk and neck is lighter (showing individual variation) and speckled with dark brown. TABLE 1. Morphometric variation in the type series of Gonatodes lichenosus sp. nov. *: holotype.⎯X ± SD: mean ± standard deviation. Specimen number

Sex

SVL

TL

HL

HW

EYN

AXG

MHNLS 19101

M

39.05

-

8.5

7.4

3.1

14

MHNLS 19109

M

41.4

-

10

8.2

3.5

17.1

MHNLS 19110

M

40.75

-

10

7.9

3.7

18.05

MHNLS 19116*

M

40.04

48.9

10.1

9

3.6

17.4

⎯X ± SD

M

40.31 ± 1.0

-

9.64 ± 0.8

8.1 ± 0.6

3.4 ± 0.3

16.64 ± 1.8

MHNLS 19107

F

40.65

46.45

9.5

7.3

3.4

17.5

MHNLS 19111

F

44.45

41

10

7.6

3.7

18.65

⎯X ± SD

F

42.55 ± 2.7

43.73 ± 3.9

9.75 ± 0.4

7.4 ± 0.2

3.5 ± 0.2

18.08 ± 0.8

Ventrally, from chin to vent the color pattern is almost uniform, varying from yellow (MHNLS 19107, 19110–19111) to ocher yellow (MHNLS 19109), between individuals, but not related with the sex. The specimens MHNLS 19107, 19110, and 19111, show several faint pale brown diagonal stripes on throat, whereas the specimen MHNLS 19109 has only small dark brown spots instead of stripes. The ventral color of the tail is quite variable: yellow finely speckled of pale brown in MHNLS 19109, skin color in MHNLS 19110, grayish beige in MHNLS 19111, and orange in MHNLS 19107 (Fig. 5b). Distribution, habitat and natural history. Known only from the type locality in the valley of Manastara, around the homonymous Yukpa indigenous community, in the Río Negro basin, eastern versant of the Sierra de Perijá, northwestern Venezuela, at 1130 m (Fig. 6). The vegetation of this altitudinal belt is described by Huber & Alarcón (1988) as ombrofilous submontane/montane evergreen forest; it extends between 800 and 2500 m asl, forming dense communities with medium to high canopy. The region has a biseasonal climatic regime, with a dry period in December–April, and a rainy period in May–November, with maximum rain peaks on May and October, and minimum on January and July (Masciangioli & Febres 2000). The Río Negro basin and particularly the valley of Manastara, although included in a protected area (Parque Nacional Sierra de Perijá), show a marked loss of the original forest, which have been replaced by grass savannas, coffee plantations (Coffea arabica L., Rubiaceae), malanga [Xanthosoma sagittifolium (L.) Schot, Araceae], and pastures for cattle. Currently the hills surrounding the valley of Manastara are almost entirely savannized, and relicts of primary forest persist only in the stepper slopes and along small streams of the valley (Figs. 7a–b). The gallery forest along the Río Negro river is basically secondary and associated with shade coffee plantations. Goats have been recently introduced in the area and roam freely in the valley of Manastara and in other nearby communities, creating an additional impact on the vegetation of the basin. The first specimen of Gonatodes lichenosus found during the survey (MHNLS 19101) was seen active at nigth (± 20 h), on the wooden post of a fence, near the indigenous community. Nocturnal activity is uncommon in these diurnal geckoes (except in G. antillensis, the only nocturnal species); however RiveroBlanco (1979) commented upon specimens of a synanthropic population of G. albogularis seen foraging at nigth near artificial light. Our specimen of G. lichenosus was not near artificial light, which suggests it may have been resting and was disturbed by our presence.

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FIGURE 6. Map of NW Venezuela showing major physiographic elements: Maracaibo Lake, and Sierra de Perijá to the west. Type locality of Gonatodes lichenosus sp. nov. is shown by a white circle.

The specimen MHNLS 19107 was found on the bark of a large tree basking head up, 1.5 m aboveground at 11 h, in a secondary gallery forest associated to a shade coffee plantation. This was the only specimen observed in a forested habitat; no other specimens were seen on trees or rocks of the secondary forest or at any nearby patch of primary forest. Nevertheless this species was frequently observed on trees, wooden fences, and other human structures in the community of Manastara, which reveal that this gecko is adaptable to changes in its habitat and can take advantage of the synanthropic environments. At least seven other species [G. albogularis, G. humeralis (Guichenot), G. petersi, G. purpurogularis Esqueda (as G. ligiae), G. siegliei Donoso-Barros, G. taniae Roze, and G. vittatus] have also been previously referred in synanthropic enviroments (Oda 2004, Rivero-Blanco 1968, 1979, Rojas-Runjaic & Rivas 2006, Rojas-Runjaic & Infante 2009, Barrio-Amorós & Molina 2010), sometimes even showing populational densities greater than those found in natural environments (Rivero-Blanco 1979). The six other specimens collected (MHNLS 19108–19111, 19116–19117) were found between 11 and 13 h, basking and foraging on tree bark, or hidden in crevices and cavities of a large tree located in an open area between the houses of the community (Figs. 7b–c). Some specimens were located up to 4 m aboveground.

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FIGURE 7. a: General view of the Manastara valley in the Sierra de Perijテ。, estado Zulia, Venezuela, area where Gonatodes lichenosus sp. nov. inhabits; b窶田: views of the Manastara community and the microhabitat where five specimens of the type series were collected.

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The same tree harbored a big colony of carpenter ants (Camponotus sp., Formicinae), and a stingless bees colony (Melipona sp., Meliponini), but no antagonistic interactions were observed between the geckoes and the stingless bees or the ants. It is possible that Gonatodes lichenosus has established a commensal relationship with these colonial insects, taking advantage of the protection that they offer to their colonies against potential predators. On March 20, 2009, an egg (7.4 mm of diameter) of Gonatodes lichenosus was found in a crevice of a rotten tree in a gallery forest at the type locality. The egg was located at about 1.2 m aboveground, nearby was a large colony of carpenter ants Camponotus sp., and a skin of Amphisbaena sp. The egg was collected and maintained in a Petri dish with lightly damp cotton. On April 24, 2009 (after 35 days), a neonate measuring SVL of 17.7 mm, and TL of 17.4 mm, hatched. None of the three other species of Gonatodes reported from Perijá (G. albogularis, G. vittatus and G. petersi) were found in the valley of Manastara; however G. petersi has been recorded from localities at similar altitudes and near the type locality of G. lichenosus, thus it is likely that these two species are sympatric in some parts of their distributions. Etymology. The specific epithet lichenosus is a Latin adjective (masculine) derived from lichen- (Latin name for composite organisms made up from symbiotic association of a fungus with a photosynthetic partner algae or cyanobacteria) + -osus (an adjectival suffix meaning “full of”). The name was given in allusion to the aspect of the dorsal color pattern (particularly on the head) of this species that resembles the complex color designs of lichens covering the bark of trees and rock surfaces in environments with high humidity.

Discussion The clusters of enlarged spinelike scales of Gonatodes lichenosus are also present in G. alexandermendesi, G. superciliaris and G. hasemani. The former two species are endemic to the Guayana region and the latter is a southern Amazonian species, yet all three species are closely related phylogenetically (Schargel et al. 2010). Additionally, although the subcaudal scale pattern of G. lichenosus is unique in the genus (1’2” basally, and 1’1” distally), the distal series of the pattern is the same as in G. alexandermendesi and G. superciliaris, as well as in G. infernalis Rivas & Schargel and G. eladioi Do Nascimento, Avila-Pires & Da Cunha, endemics from the Guayana and Amazonia, respectively. Given that Gonatodes lichenosus only shares these two character states with some Guayanan and Amazonian species, and it is quite different morphologically from the Andean species, particularly from those inhabiting the Sierra de Perijá (G. albogularis, G. petersi and G. vittatus), it is likely that this new species is more closely related to the species of the “Guayana Shield clade” (see Schargel et al. 2010) than to other geographically closer congeners. If Gonatodes lichenosus is indeed closely related to the Guayana Shield clade then it is likely that the current diversity of Gonatodes in the Sierra de Perijá has resulted, at least in part, from more than one colonization event from different ancestral lineages. Nevertheless, the inclusion of G. lichenosus in future phylogenetic studies will be necessary in order to clarify its position in the genus, and contribute to understanding the evolutionary processes responsible for the current diversity of Gonatodes in Perijá. Gonatodes species are generally sexually dichromatic, with males being conspicuously ornamented with bright colors, whereas females are always cryptically colored (Rivero-Blanco 1979). Sexual dichromatism has traditionally been thought to result from sexual selection (Andersson 1994), and can be related to female mate choice or male-male competition (Wiens 2001). Gonatodes lichenosus is unique among species of this genus as it is the only species not showing sexual dichromatism. Loss of male-specific traits, although very rare in Gonatodes, is apparently very common and widespread in all major groups of vertebrates (Wiens 2001). The evolution of sexual dichromatism results from a trade-off between sexual selection for conspicuous coloration and natural selection via differential predation pressure (Stuart-Fox & Ord 2004). The loss of sexually selected traits implies that natural selection eventually is able to overcome the power of sexual selection, or that sexual selection might become weaker or reverse direction over time, or both (Wiens 2001). Stuart-Fox & Ord (2004) determined that dichromatism of exposed body regions (e.g. dorsal and lateral

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surfaces) is significantly associated with habitat openness, and that species occupying open habitats tend to be less sexually dichromatic than species in more closed habitats. These authors suggested that species occupying open habitats are potentially more vulnerable to visual predators, so that natural selection for crypsis may override or constrain sexual selection for conspicuous coloration in males, resulting in less sexual dichromatism or cryptic color in both sexes. Gonatodes lichenosus was found principally inhabiting open habitats and both sexes show the same cryptic pattern, by which this species could be a good candidate for behavioral studies in order to evaluate the above hypothesis as an explanation for the absence of sexual dichromatism in this gecko. Gonatodes lichenosus has another curious characteristic: both males and females of this species show a vivid yellow ventral color. Wiens (2001) commented that a pattern of sexual monomorphism due to acquisition by females of the same conspicuous traits seen in males, can be related to male mate choice or female-female competition, and also appears to be widespread among lizard species. In view of the particularity of the secondary sexual traits of G. lichenosus and their possible ecological and evolutionary implications, this species potentially represents a good model for future studies of sexual selection and the evolution of sexual dichromatism.

Acknowledgments We thank Amelio Gutiérrez and César Romero for field assistance during the expedition to Manastara Valley, where the type series was collected. Also we thank Gabriel N. Uguetto, Walter E. Schargel, César .L. BarrioAmorós, and Andrew J. Crawford for improving this manuscript with their comments, suggestions and English editing. Financial support was provided to Fernando J.M. Rojas-Runjaic by Banco Federal through the project FED-MHNLS-09 “Inventario de las especies de anfibios y reptiles de la vertiente venezolana de la Sierra de Perijá, estado Zulia”, under the auspices of “Ley Orgánica de Ciencia, Tecnología e Innovación”. Collecting permit No. 4750 (period 2008–2009) was issued by the Venezuelan Ministerio del Poder Popular para el Ambiente. Expeditions to the Río Tukuko basin (Parque Nacional Sierra de Perijá) were made posible by permission of the Venezuelan Instituto Nacional de Parques (PAA-215-2008) issued to Fernando J.M. Rojas-Runjaic.

References Andersson, M. (1994) Sexual Selection. Princeton University Press, Princeton, New Jersey, 624 pp. Avila-Pires, T.S.C. (1995) Lizards of Brazilian Amazonia (Reptilia: Squamata). Zoologische Verhandelingen, 299, 1– 706. Barrio-Amorós, C.L. & Brewer-Carias, C. (2008) Herpetological results of the 2002 expedition to Sarisariñama, a tepui in Venezuelan Guayana, with the description of five new species. Zootaxa, 1942, 1–68. Barrio-Amorós, C.L. & Molina, C. (2010) Apéndice 8. Catálogo ilustrado de los anfibios y reptiles del ramal de Calderas, Andes de Venezuela. In: Rial B., A., Señaris, J.C., Lasso, C.A. & Flores, A. (Eds.) Evaluación rápida de la biodiversidad y aspectos socioecosistémicos del Ramal Calderas, Andes de Venezuela. RAP Bulletin of Biological Assesment 56. Conservation International, Arlington, pp. 141–156. Barrio-Amorós, C.L., Rojas-Runjaic, F.J.M. & Infante R., E.E. (2007) Tres nuevos Pristimantis Jiménez de la Espada (Anura: Strabomantidae) de la Sierra de Perijá, estado Zulia, Venezuela. Revista Española de Herpetología, 21, 71– 94. Barrio-Amorós, C.L., Rojas-Runjaic, F. & Barros, T.R. (2010) Two new Pristimantis (Anura: Terrarana: Strabomantidae) from the Sierra de Perijá, Venezuela. Zootaxa, 2329, 1–21. Esqueda, L.F. (2004) Una nueva especie de Gonatodes (Squamata: Gekkonidae) proveniente del piedemonte cisandino de Venezuela. Herpetotropicos, 1, 32–39. Huber, O. & Alarcón, C. (1988) Mapa de vegetación de Venezuela. 1:2.000.000. Infante R., E.E., Barrio-Amorós, C.L. & Rojas-Runjaic, F.J.M. (2006a) Geographic Distribution: Anura: Phyllomedusa venusta. Herpetological Review, 37, 101. Infante R., E.E., Rojas-Runjaic, F.J.M. & Barrio-Amorós, C.L. (2006b) Geographic Distribution: Anura: Relictivomer

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pearsei. Herpetological Review, 37, 102–103. Infante-Rivero, E.E., Rojas-Runjaic, F.J.M. & Barrio-Amorós, C.L. (2008) Un nuevo Cryptobatrachus Ruthven, 1916 (Anura, Cryptobatrachidae) de la vertiente venezolana de la Sierra de Perijá. Memoria de la Fundación La Salle de Ciencias Naturales, 68, 45–63. Infante-Rivero, E.E., Velozo, P. & Rojas-Runjaic, F.J.M. (2009) Primer registro del lagarto Anolis apollinaris, para Venezuela. Boletín del Centro de Investigaciones Biológicas, 43, 299–304. Masciangioli, P. & Febres, G. (2000) Climatología de la cuenca de Maracaibo. In: Rodríguez, G. (Ed.), El sistema de Maracaibo, Biología y Ambiente. Second edition. Instituto Venezolano de Investigaciones Científicas, Caracas, pp. 21–32. Oda, W.Y. (2004) Comunal egg laying by G. humeralis (Sauria, Gekkonidae) in Manaus primary and secondary forest areas. Acta Amazonica, 34, 331–332. Powell, R. & Henderson, R.W. (2005) A new species of Gonatodes (Squamata: Gekkonidae) from the West Indies. Caribbean Journal of Science, 41, 709–715. Rivas, G.A. & Schargel, W.E. (2008) Gecko on the rocks: an enigmatic new species of Gonatodes (Sphaerodactylidae) from Inselbergs of the Venezuelan Guayana. Zootaxa, 1925, 39–50. Rivero-Blanco, C. (1968) Un género y dos especies de tuqueques (Sauria: Sphaerodactylinae) citados por primera vez para Venezuela, con notas sobre la distribución de otras especies poco conocidas. Memoria de la Sociedad de Ciencias Naturales La Salle, 77, 103–119. Rivero-Blanco, C. (1979) The Neotropical lizard genus Gonatodes Fitzinger (Sauria: Sphaerodactylinae). PhD Dissertation, Departament of Wildlife Fisheries Sciencies, Texas A&M University, College Station, Texas, 233 pp. Rojas-Runjaic, F.J.M. & Infante R., E.E. (2006) Reptilia, Squamata, Colubridae, Chironius exoletus: distribution extension, new state record. Check List, 2, 82–83. Rojas-Runjaic, F.J.M. & Infante R., E.E. (2008) First record of the forest racer snake Dendrophidion percarinatum (Cope, 1893) (Serpentes: Colubridae) from Venezuela. Caribbean Journal of Science, 44, 128–130. Rojas-Runjaic, F.J.M. & Infante R., E.E. (2009) Redescripción de Gonatodes petersi Donoso-Barros, 1967 (Squamata: Gekkonidae), un tuqueque endémico de la vertiente venezolana de la sierra de Perijá. Memoria de la Fundación La Salle de Ciencias Naturales, 170, 81–98. Rojas-Runjaic, F.J.M. & Rivas F., G.A. (2006) Notes on the natural history and geographic distribution of Gonatodes petersi Donoso-Barros, 1967 (Sauria; Gekkonidae): an endemic and poorly known gecko of the sierra de Perijá, Venezuela. Gekko, 5, 21–25. Rojas-Runjaic, F.J.M., Infante R., E.E., Barrio-Amorós, C.L. & Barros B., T. (2007) New Distributional Records of Amphibians and Reptiles from Estado Zulia in the Maracaibo Basin, Venezuela. Herpetological Review, 38, 235– 237. Rojas-Runjaic, F.J.M., Infante-Rivero, E.E., Señaris, J.C. & Cabello, P. (2010) Amphibia, Anura, Centrolenidae, Centrolene daidaleum (Ruiz-Carranza and Lynch, 1991): First record for Venezuela, new altitudinal record, and distribution map. Check List, 6, 460–462. Schargel, W.E., Rivas, G.A., Makowsky, R., Señaris, J.C., Natera, M.A., Barros, T.R., Molina, C.R. & Barrio-Amorós, C.L. (2010) Phylogenetic systematics of the genus Gonatodes (Squamata: Sphaerodactylidae) in the Guayana region, with description of a new species from Venezuela. Systematics and Biodiversity, 8, 321–339. Stuart-Fox, D.M. & Ord, T.J. (2004) Sexual selection, natural selection and the evolution of dimorphic coloration and ornamentation in agamid lizards. Proceedings of the Royal Society of London, 271, 2249–2255. Viloria, A.L. & Calchi La C., R. (1993) Una lista de los vertebrados vivientes de la Sierra de Perijá, Colombia y Venezuela. Biollania, 9, 37–69. Wiens, J.J. (2001) Widespread loss of sexually selected traits: how the peacock lost its spots. Trends in Ecology and Evolution, 16, 517–523.

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Appendix 1. Specimens examined Gonatodes albogularis (2).- VENEZUELA: Estado Zulia: Misión El Tokuko, Sierra de Perijá, MHNLS 9637; Municipio Machiques de Perijá, Misión de los Ángeles del Tokuko, cuenca del río Tokuko, Sierra de Perijá, MHNLS 19025. Gonatodes antillensis (2).- VENEZUELA: Dependencias Federales: Isla Larga, Archipiélago Las Aves, MHNLS 2185, 2188. Gonatodes annularis (5).- VENEZUELA: Estado Bolívar: Campamento Base, bajo Río Uey, tributario Río Cuyuní, MHNLS 18706–18707; Municipio Sifontes: Piedra de la Virgen, Sierra de Lema, MHNLS 19594–19596. Gonatodes astralis (1).- VENEZUELA: Estado Amazonas: Municipio Atures: Entre las comunidades de La Reforma y Danto, carretera Puerto Ayacucho-Gavilán, MHNLS 20005. Gonatodes ceciliae (2).-VENEZUELA: Estado Sucre: Río Salao, approximately 3 km NW of the base camp, Península de Paria, MHNLS 12314–12315 Gonatodes concinnatus (1).- PERU: Departamento Loreto: Moropón, MHNLS 8561 (formerly MZUSP 28251). Gonatodes humeralis (2).-VENEZUELA: Estado Bolívar: Municipio Cedeño: Pica de bosque de rebalse, entre campamento de Caño Mato y Caño Cuchiverito, cuenca Del Río Caura, MHNLS 19693–19694. Gonatodes infernalis (2).-VENEZUELA: Estado Amazonas: Sector El Infierno, carretera Puerto Ayacucho-Gavilán, MHNLS 18439–18440 (paratype and holotype respectively) Gonatodes lichenosus (9).- VENEZUELA: Estado Zulia: Municipio Machiques de Perijá, Sierra de Perijá, Manastara, Yukpa indigenous community, Río Negro basin, Parque Nacional Sierra de Perijá, MHNLS 19116 (holotype), MHNLS 19101, 19107, 19109, 19110–19111 (paratypes), MHNLS 19108, 19117, and 19160. Gonatodes petersi (4).- VENEZUELA: Estado Zulia: Municipio Machiques de Perijá, Toromo, Río Negro, Sierra de Perijá, MHNLS 18140–18141; Misión El Tokuko, Sierra de Perijá, MHNLS 9638, 9643. Gonatodes purpurogularis (3).- VENEZUELA: Estado Barinas: Municipio Bolívar, Calderas, Balneario La Piedra Del Patio, MHNLS 18593, 18598–18599. Gonatodes taniae (2).- VENEZUELA: Estado Aragua: Rancho Grande, MHNLS 464–465. Gonatodes vittatus (3).- VENEZUELA: Estado Zulia: Municipio Mara, segundo cruce Del Río Maché, entre el Fundo La Orchila y la Hacienda La Carpa, Sierra de Perijá, MHNLS 17470; Municipio Mara: Hacienda La Carpa, Riecito Maché, Sierra de Perijá, MHNLS 17472; Municipio Colón: Sector La Maroma, junto a la Hacienda Las Delicias, MHNLS 18451.

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