Zootaxa 3518: 66–78 (2012) www.mapress.com / zootaxa/ Copyright © 2012 · Magnolia Press
ISSN 1175-5326 (print edition)
ZOOTAXA ISSN 1175-5334 (online edition)
A strikingly polychromatic new species of Gonatodes (Squamata: Sphaerodactylidae) from northern Venezuela CARLOS RIVERO-BLANCO1 & WALTER E. SCHARGEL2* 1
Ave. Páez, Resid. General Páez, Edif. B-33, El Paraíso, Caracas 1020, Venezuela. E-mail: email@example.com Department of Biology, The University of Texas at Arlington, Arlington, TX 76019, USA. E-mail: firstname.lastname@example.org. *corresponding author 2
Abstract We describe a new species of diurnal gecko, Gonatodes rozei sp. nov., from tropical and premontane humid forests of north central Venezuela. The new species can be distinguished from other congeners by a combination of large size, subcaudal pattern B (1’1’1’’), three or four lateral scale rows on the digits, males with blue iris, scalation of the gular area, and aspects of color pattern in males and females. The new species is strongly sexually dichromatic and up to four different color morphs are observed in males. Keywords: gecko, lizard, reptile, taxonomy, polymorphic .
Introduction The neotropical genus Gonatodes represents a group of mostly diurnal geckos that currently contains 28 species (Rojas-Runjaic et al. 2010; Schargel et al. 2010; Sturaro & Avila-Pires 2011; Kok 2011) collectively distributed from southern Mexico in the north, to Bolivia and Brazil in the south, and including also many islands of the Antilles (Rivero-Blanco 1979). The phylogenetic relationships of members of this genus have been examined recently and its monophyly seems well corroborated (Gamble et al. 2008; Schargel et al. 2010). However, several new species remain to be described and other taxonomic changes are likely (Rivero-Blanco 1979; Schargel 2008; Schargel et al. 2010). The taxonomy of Gonatodes has been especially dynamic in Venezuela, with five species being described in recent years from this country (Esqueda 2004; Barrio-Amorós & Brewer-Carías 2008; Rivas & Schargel 2008; Rojas-Runjaic et al. 2010; Schargel et al. 2010). One of the most striking features of Gonatodes is that most species are highly sexually dichromatic. Whereas females are cryptically colored, males tend to have bright-colored (yellow, red, green, orange) markings on the head, sides of the body, and even the underside of the tail (Rivero-Blanco 1979). Furthermore, in several species of Gonatodes there are remarkable, within population, discrete differences in coloration in males (male polychromatism), with some species having up to three well-defined color morphs (Rivero-Blanco 1968; Schargel 2008; Schargel et al. 2010). Herein we describe a new species of Gonatodes from north central Venezuela that shows the most extreme levels of variation in male coloration yet documented in the genus. In this new species up to four different male color morphs can be found within the same locality.
Materials and methods Specimens examined are deposited in the herpetological collections of the British Museum on Natural History (BMNH), Museo de Biología de la Universidad Central de Venezuela (MBUCV), Museo de Ciencias Naturales de Caracas (MCNC), Museo de Historia Natural La Salle in Caracas (MHNLS), the University of Texas at Arlington (UTA) and the Texas Cooperative Wildlife Collection (TCWC). We used a digital caliper to measure snout-vent
66 Accepted by A. Bauer: 18 Sept. 2012; published: 16 Oct. 2012
length (SVL) and tail length to the nearest tenth of a millimeter. Specimens were sexed by examining the sexually dimorphic color pattern common to species in Gonatodes in conjunction with examining the base of the tail, which is notably bulky in males due to the presence of the hemipenes. When in doubt, a small cut was made at the base of the tail to check for the presence of hemipenes. The species description follows the format used by Rivas & Schargel (2008) and Schargel et al. (2010), which was modified slightly from Avila-Pires (1995). For the purpose of facilitating comparisons between species of Gonatodes we describe the character states and taxonomic distribution of two characters that have proven useful in the systematics of the genus. Size. There is significant interspecific size variation in Gonatodes, with the largest species (G. infernalis Rivas & Schargel) having a SVL that is about 2.2 times that of the smallest species (G. daudini Powell & Henderson). The size distribution within the genus is slightly bimodal, with the majority of species being either greater than 49 mm or less than 42 mm in maximum SVL. Additionally, size in Gonatodes appears to have significant phylogenetic signal given that similar sized species tend to be closely related (see the phylogenetic trees presented by Gamble et al. 2008, and Schargel et al. 2010). We group the species of Gonatodes into three different size categories as detailed below. We are aware that these categories are arbitrary but they were delimited to separate the two size modes (large and small size) in the best way possible, leaving only a few species that are intermediate in size placed into their own category (medium). Some of the medium size species remain poorly known (e.g. G. falconensis Shreve and G. seiglei Donoso-Barros), and additional samples might reveal larger individuals. The data on maximum size for species of Gonatodes was obtained from Rivero-Blanco (1979), Avila-Pires (1995), MijaresUrrutia & Arends (1995), Esqueda (2004), Cole & Kok (2006), Barrio-Amorós & Brewer-Carías (2008), Rivas & Schargel (2008), Schargel et al. (2010), Rojas-Runjaic et al. (2010), Sturaro & Avila-Pires (2011) and Kok (2011). Large: includes species with adults attaining a SVL higher than 49 mm. The large species in the genus are G. alexandermensi Cole & Kok, G. annularis Boulenger, G. ceciliae Donoso-Barros, G. concinnatus O’Shaughnessy, G. infernalis, G. nascimentoi Sturaro & Avila-Pires, G. purpurogularis Esqueda, G. taniae Roze, G. timidus Kok, G. superciliaris Barrio-Amorós & Brewer-Carías, G. tapajonicus Rodrigues, and the new species described below. Medium: includes species with adults attaining a SVL that exceeds 42 mm but that do not reach 49 mm. The medium species in the genus are G. astralis Schargel, Rivas, Makowsky, Señaris, Barros, Molina & BarrioAmorós, G. falconensis, G. hasemani Griffin, G. lichenosus Rojas-Runjaic, Infante-Rivero, Cabello & Velozo, G. ocellatus Gray, G. riveroi Sturaro & Avila-Pires, and G. seiglei. Small: includes species with adults attaining a SVL not exceeding 42 mm. The small species in the genus are G. albogularis Dúmeril & Bibron, G. antillensis Lidth de Jeude, G. atricucullaris Noble, G. caudiscutatus Günther, G. daudini, G. eladioi Do Nascimento, Avila-Pires & Cunha, G. humeralis Guichenot, G. ligiae Donoso-Barros, G. petersi Donoso-Barros, and G. vittatus Lichtenstein. Subcaudal scale pattern. Rivero-Blanco (1979) first presented in his unpublished dissertation a description and taxonomic distribution of the different types of subcaudal patterns found in Gonatodes. Subsequent to his work this character has been used several times to separate species in the genus (Avila-Pires 1995; Esqueda 2004, Rivas & Schargel 2008; Schargel et al. 2010; Kok 2011; Sturaro & Avila-Pires 2011) and Avila-Pires (1995) has proposed an easy way of coding it. However, a full account of this character has never been formally published and we find this to be a good opportunity to correct this problem. There are seven different types of subcaudal scale patterns in Gonatodes, distinguished from each other by the arrangement of the medial scales. These are described below (see also Fig. 1 for a diagrammatic representation of all the different subcaudal scale types) along with their taxonomic distributions within the genus (notice that species can be variable for subcaudal patterns). The coding method proposed by Avila-Pires (1995) for this character is shown in parenthesis. Type A: (1’1’2’’) there are large divided medial scales in contact laterally with three scales, separated from each other by two smaller undivided medial scales, each in contact laterally with two scales. The species with this subcaudal type are: G. albogularis, G. annularis, G. antillensis, G. daudini and G. purpurogularis. Type B: (1’1’1’’) there are large, undivided medial scales in contact laterally with three scales, separated from each other by two smaller undivided medial scales, each in contact laterally with two scales. The species with this subcaudal type are: G. albogularis, G. atricucullaris, G. caudiscutatus, G. ceciliae, G. concinnatus, G. falconensis, G. humeralis, G. ligiae, G. nascimentoi, G. ocellatus, G. petersi, G. purpurogularis, G. riveroi, G. taniae, G. tapajonicus, G. vittatus and the new species described below. Type C: (1’1’’) there are large, undivided medial scales in contact laterally with three scales, separated from each other by a smaller, undivided medial scale, in contact laterally with two scales. The species with this
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subcaudal pattern are: G. alexandermendesi (erroneously reported as type B in original description), G. eladioi, G. infernalis, G. superciliaris and G. timidus. Type D: (1’1’’ proximally, 1’1’1’’ distally) this subcaudal pattern type is a combination of types C and B. Type C (the large medial scales alternate with the small medial scales in a 1:1 fashion) occurs in the proximal portion of the tail, but the pattern changes to Type C (the large and small medial scales alternate in a 1:2 fashion) distally. The only species with this subcaudal pattern is G. seiglei. Type E: this is the only subcaudal type in which the midventral scales are not distinct from the rest of the scales on the tail. The species with subcaudal pattern F are G. astralis, G. hasemani, and G. annularis. Type F: (1’1’2’’ proximally, 1’1’1’’ distally) this subcaudal pattern type is a combination of types A and B. Type A occurs proximally but Type B replaces it distally. The species with type E subcaudal pattern are G. albogularis, G. concinnatus, G. nascimentoi, G. purpurogularis, G. riveroi, and G. tapajonicus. Type G: (1’2’’ proximally, 1’1’’ distally) proximally there are large, divided subcaudal scales in contact with three scales laterally, separated from each other by a smaller, undivided scale in contact laterally with two scales. Distally the tail becomes type C. The only species with subcaudal pattern G is G. lichenosus.
FIGURE 1. Diagrammatic illustration of the seven (A–G) different subcaudal scale patterns found in the genus Gonatodes.
Gonatodes rozei sp. nov. (Figs. 2, 3, 4, 5) Holotype. MHNLS 20780, an adult male, collected by G. Rivas and W. Schargel, September 17, 2006, 3 km SW of Araguita (10 12’58’’ N, 66 29’07’’ W; ca. 150 m asl), near limit of Guatopo National Park, Miranda, Venezuela.
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Paratypes (n=39). VENEZUELA: MIRANDA: 32.9 Km N of Altagracia de Orituco, Guatopo National Park: TCWC 59300–59306. Guatopo National Park: MBUCV 5044, MHNLS 1666–1669, 1674–1677, 2082. GUÁRICO: 5 km E of “Puesto La Colonia,” Guatopo National Park: TCWC 59319–59320. 25.2 km N of Altagracia de Orituco, Guatopo National Park: TCWC 59318. Hacienda La Elvira, Guatopo National Park: UTA 60126, TCWC 59309–59317, 59321.
FIGURE 2. Adult male (top, holotype, MHNLS 20780) and adult female (bottom, UTA 60126) of Gonatodes rozei sp. nov. in life.
Referred specimens (n=83). VENEZUELA: ANZOÁTEGUI: Valle de Guanape: MHNLS 5532. GUÁRICO: Las Palmas, Altagracia de Orituco: MBUCV 3253. MIRANDA: Araira, Hacienda La Ceiba: MHNLS 15177–15178. Capaya: MHNLS 2322, 2324–2325, 5143–5145, 5854, MCNC 3719–3726, 3776. Taica: NEW GONATODES FROM VENEZUELA
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MHNLS 2162. Carenero: MBUCV 5045, Carretera Chuspa – Higuerote, MHNLS 3775. Cueva 105, El Encantado: MHNLS 1982. Cueva Alfredo Jahn: MBUCV 8415, MHNLS 2323. Cueva Cruxent, Curiepe: MHNLS 2248, 2250. Cueva de la Diaclesa, El Encantado: MHNLS 1985. Cueva Graciliano, Curiepe: MHNLS 2249. Cueva del túnel 4, Los Naranjos: MHNLS 1883–1884, 1981, 2161. El Encantado: MBUCV 5043. Los Naranjos: MHNLS 2161. Planta Eléctrica Los Naranjos, Río Guaire: BMNH 1967.256–257, MCNC 3754–3759. Quebrada Rebollero, Chuspa: MCNC 3735. Quebrada Urba, Carretera Panaquire – El Sapo: MHNLS 16780, 16786. VARGAS: Cerro Naiguatá, “two hours from toma de agua:” MHNLS 3774. Hacienda El Limón: MHNLS 2060, 4296, 4297, 4362, 4363, 4392, 4532, 4651, 4690, 4813. Pico Naiguatá: MCNC 3733–3734. Piedra del Zamuro, Carayaca: MCNC 3736–3753. Planta Eléctrica de Naiguatá: MCNC 3727–3732. Etymology. We take great pleasure in naming the new species after Dr. Janis Roze, a pioneer of Venezuelan herpetology and a mentor to CRB for many years. Diagnosis. The new species can be distinguished from all congeners by a combination of the following characters: (1) large size (largest specimen examined has a SVL of 59.1 mm), (2) 78–100 scales around midbody, (3) single, elongated supraciliary spine absent, (4) three or four lateral scale rows on the digits, (5) subcaudal pattern Type B, (6) gular scales posterior to the postmentals with a sharp transition to small granular scales, (7) males with blue iris (females blue or yellow), and (8) males typically with an immaculate bright yellow to reddish orange hood. The large size of G. rozei readily distinguishes this species from the small species in the genus, namely G. albogularis, G. antillensis, G. atricucullaris, G. caudiscutatus, G. daudini, G. eladioi, G. humeralis, G. ligiae, G. petersi, and G. vittatus, none of which exceed 42 mm in SVL. Gonatodes rozei further differs from the small species, except G. caudiscutatus and G. ligiae, in having three (rarely) or four (typically) lateral rows of scales on the distal portion of the digits as opposed to two. Males of the new species generally have a solid yellow or reddish yellow head whereas in G. caudiscutatus the head is always covered with yellow stripes. Specimens of G. rozei have fewer scales around midbody compared to G. ligiae (78–100 vs. 109–128, respectively). Among the large and medium size species (character states in parenthesis), G. rozei differs from G. astralis, G. alexandermendesi, G. hasemani, and G. superciliaris in lacking an elongated supraciliary spine (a single elongated spine is present). It differs from G. annularis in having subcaudal pattern type B (type A or E) and a body devoid of yellow reticulations in males (body almost always covered with yellow reticulations in males). It differs from G. infernalis in having subcaudal pattern type B (type C) and having females with a brown dorsal coloration with dark and pale markings and a pale vertebral stripe (females with immaculate brown dorsal coloration; males not known for this species). Gonatodes rozei differs from G. ceciliae, G. concinnatus, G. nascimentoi, G. ocellatus, G. riveroi, and G. tapajonicus in lacking a suprahumeral/suprascapular pale spot/bar edged by black as opposed to having a distinct (especially in males), pale (white or yellow) spot/bar edged by black located around the scapular area, either anteriorly or posteriorly relative to the front limb insertion. It further differs from G. concinnatus, G. nascimentoi, and G. tapajonicus in having fewer scales around midbody (<101 in G. rozei as opposed to >108 in the aforementioned species). Males of these three species, together with G. riveroi, are reddish brown dorsally with small, yellow and white vermiculations densely covering the body (see color variation for G. rozei below). Gonatodes rozei lacks red, olive green and yellow reticulations on the body as observed in males of G. ceciliae. Gonatodes ocellatus is a smaller species that does not exceeds 49 mm in SVL. Gonatodes rozei differs from G. lichenosus and G. seiglei in having a subcaudal pattern type B as opposed to type G and D, respectively. Gonatodes rozei is found in close geographic proximity (Schargel, unpublished data) with G. falconensis and G. taniae, so the comparisons with these two species need to be more exhaustive. Gonatodes purpurogularis (endemic to the Mérida mountain range) is not found in close geographic proximity to G. rozei but this species forms a well-supported clade with G. falconensis and G. taniae (see Schargel et al. 2010), and all three species are very similar morphologically. These three species will be referred to as the falconensis complex in the comparisons in instances for which they all share the same character state. Males of G. falconensis have dull red or reddish brown markings, typically forming short stripes, on the head, sometimes on the body. Males of G. taniae have distinct white stripes (which remain conspicuous in museum specimens) on the head, including most noticeably canthal, postocular and postrictal stripes. In G. purpurogularis the white markings on the head are also present but they are short, not forming stripes. In contrast to what is observed in the falconensis complex, males of G. rozei have most commonly a solid yellow/orange (which fades to cream) head or, less frequently, irregular yellow reticulations on the head. Males of the falconensis complex have bright yellow coloration (fades in preserved specimens; variable in G. falconensis) suffused on the sides of the body over a pale gray background. Body
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coloration is variable (see variation section) in G. rozei, but we have not observed specimens with bright yellow coloration on the body. Females of the falconensis complex have a wide (expanding to the dorsolateral area), pale, middorsal, longitudinal band with straight edges. This band contains either an irregular, dark, vertebral stripe or a series of paired, paravertebral, dark spots. In females of G. rozei there is a pale, vertebral stripe which does not expand to the dorsolateral area and, as opposed to the middorsal band of the aforementioned species, the lateral edges are strongly undulating. Females of the falconensis complex have pale yellow or white transverse dashes on the sides of the body, whereas females of G. rozei have white dots on the side of the body. Regarding aspects of morphology other than color pattern, the three species of the falconensis complex have a scalation pattern in the gular area in which the scales posterior to the postmentals gradually transition from larger polygonal and juxtaposed scales into smaller imbricate scales (Schargel unpublished); whereas in G. rozei the scales posterior to the postmentals transition sharply into smaller, granular scales (Fig. 3).
FIGURE 3. Scalation pattern in the gular area of Gonatodes rozei sp. nov. (left; illustration based on MHNLS 5532 from Valle de Guanape, Anzoátegui, Venezuela) and the falconensis complex (right; illustration based on specimen of G. taniae, TCWC 59378, from Rancho Grande, Aragua, Venezuela).
Finally, G. rozei and G. annularis are the only two species of Gonatodes in which the iris of the eye is blue in life (always the case in males but variable in females). In all other species in the genus the iris is yellow, bronze, copper or red. Description of holotype. An adult male (Fig. 2), with snout-vent length of 59.1 mm. Tail length 57.3 mm, complete but regenerated. Head about 1.4 times longer than wide (head length: 13.6 mm; head width: 10.0 mm). Snout short (eye-nostril distance is 4.2 mm), 0.3 times head length, somewhat acutely rounded in dorsal view, sloping toward top of head with an approximate 45º angle in lateral view. Lower jaw slightly projecting past the tip of the snout, visible in dorsal view. Neck 7.3 mm wide (shortest distance), narrower than head and body. Body subcylindrical, wider than high; axilla-groin distance 27.6 mm. Limbs well developed with moderately long digits, fourth toe length 7.9 mm, 0.95 times shank length (8.3 mm, from base of palm to knee). Tail round in cross section, tapering towards tip. Tongue relatively wide with bluntly rounded tip, covered by small, scale-like papillae, which become less defined posteriorly; tip of tongue with very short median cleft; anterior portion of tongue gray, fading posteriorly. Teeth very small, subequal, conical. Rostral moderately large, visible from above, irregularly shaped, much wider than high, but with a small longitudinal groove that divides the scale almost completely except for a short section towards the lip. Three postrostrals, lateral ones (supranasals) distinctly larger than the single median scale, which is about the same size as the scales on the snout; posterior to the medial postrostral a slightly larger, single scale, separates the lateral postrostrals from contacting each other. Nostril bordered by rostral, four (left) or three (right) postnasals, and lateral postrostral (=supranasal). Three/four postnasals, on average slightly larger than scales on the loreal region. Scales on top of snout and loreal region basally round, granular to subconical, juxtaposed. Loreal scales number about 13/ 15 in a line between postnasals and anterior margin of eye socket. Scales decrease slightly in size from the
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postrostrals toward posterior part of head. Scales on supraorbital slightly smaller and more granular than those on top of head. A moderate supraciliary flap bears three well-developed spines located roughly above the center of the eye. The supraciliary scales anterior to these spines are flat and larger than those on the supraorbital region; posterior to the well-developed spines the supraciliary scales are tiny and granular although a few of these scales project laterally in the form of short and poorly developed spines. Pupil round. Supralabials 6/6 to level of center of eye of which the first is the largest, first few bearing minute tubercles; sixth supralabial followed by about 10/12 tiny, granular scales along the lip to rictus of mouth; these tiny scales about same size as those on temporal region. Scales on temporal region similar to those on posterior top of head. Ear opening (1.3 mm) much smaller than eye (2.7 mm), obliquely oval. Mental large, with bluntly rounded anterior margin and three roughly straight sides on posterior margin. Postmentals three, distinctly larger than adjacent posterior scales. Scales on chin small, granular, a few larger, roughly elliptical scales adjacent to infralabials, juxtaposed. Infralabials 4/4 to level of center of eye, decreasing in size posteriorly, first two very large and projecting onto ventral plane. Scales on nape and on sides of neck granular to slightly conical. Scales on throat smooth, imbricate, with round posterior margin, with a short transitional area with granular scales on gular area. Dorsals granular, oval-shaped at base, heterogeneous in size, but majority slightly larger than scales on top of head. Transition between scales on flanks and ventrals abrupt but with a few scales of intermediate morphology. Ventral scales distinctly larger than dorsals, slightly smaller on chest than on belly, smooth, imbricate (each scale overlapping anterior portion of scale lying posteriorly), with round posterior margin, arranged for the most part in oblique rows. There are 47 scales along the midventral line between the level of anterior margin of forelimbs and the small scales anterior to vent. Scales around midbody about 81, of which about 17 are ventrals. Scales on precloacal region similar to ventrals, except proximally to vent, which has minute scales arranged in several rows. Escutcheon distinct, with a vertex projecting anteriorly just past level of groin; posterior margin of escutcheon slightly concave, 3.3 mm from vent. On ventral surfaces of posterior limbs, escutcheon is 3â€“4 scales wide and extends medially for almost full extent of thighs. Scales dorsally on tail slightly larger than on body, flat, slightly imbricate, with round posterior margin; a short transition area between the granular body scales and the caudal scales just described, extends posteriorly about 4 mm from base of tail. Underside of tail covered with flat, wide, short, roughly rectangular plates on regenerated part. Underside of unregenerated part of tail extends about 8 mm from vent, of which proximal 4 mm are covered with scales like those in venter but slightly smaller and distal 4 mm show the beginning of the pattern of differentiated scales (subcaudal pattern type B). Scales on anterior limbs tiny, granular and juxtaposed, except narrowly on anterior margin of forearm, on which scales tend to be bigger, flat and imbricate. Scales on posterior limbs small, granular and juxtaposed on dorsal, posterior and posterior half of ventral surfaces; flat, imbricate, about same size as scales on venter, on anterior and anterior half of ventral surface; on ventral surface of posterior limbs there is a sharp transition between the two types of scales that coincides with posterior margin of escutcheon. Lamellae under first (I) through fifth (V) finger (infraproximals in parentheses; right/left): I: 14/14(3/3), II: 20/19 (6/6), III: 23/24(7/7), IV: 24/24(8/8), and V: 19/19(5/5), respectively. Lamellae under first through fifth toe (infraproximals in parentheses): I: ?/11(?/2), II: 18/19(4/6), III: 24/24(8/7), IV: 26/26(10/9), and V: 22/22(6/6), respectively. Fingers and toes with four lateral rows of scales distally. Claws exposed, non-retractile, between two or three basal scales. Color in life and preservative. In life (Fig. 2) the dorsal and lateral surfaces of the body and front legs have dark, smoky gray background coloration. This background coloration turns grayish brown dorsally and laterally on the tail and the back legs. The dorsum, flanks, front legs and thighs, are covered with black edged, white ocelli. The black edges are vaguely defined, as they gradually fade into the background coloration. The largest ocelli are about one third (white region only) the size of the eye and are located on the anterior part of the body. The ocelli become smaller and sparser on the posterior part of the body and do not extend past the base of the tail. A bright yellow hood covers the head completely, including ventrally, extending posteriorly to the level of the anterior margin of the front limbs. This yellow hood has some areas suffused with orange, most significantly on a patch on the left temporal region, which seems to be a scar possibly produced by male-male combat. The ventral surface of the body, except the scutcheon area, appears macroscopically as a mottled pale grey pattern on a white background; under magnification the mottled appearance is conferred by the arrangement of melanophores, which are concentrated towards the edges, on the ventral scales. The color in preservative has not changed significantly,
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FIGURE 4. The four different male color morphs in Gonatodes rozei sp. nov., I-IV, arranged from top to bottom. Illustration by Emil Bröckl.
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except the head, which has faded to cream, and the background coloration of the body, which has faded slightly to a paler gray tone. Variation. The largest male is the holotype measuring 59.1 mm in SVL. TCWC 59312 and 59320 are the largest females both measuring 55.3 in SVL. There are typically five, less frequently four or six supralabials 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. There are typically four or five, rarely six, infralabials to the level of the center of eye, followed posteriorly by 1–2 small polygonal scales and subsequently by multiple tiny granular scales. Postrostrals 3–4. Postmentals 2–4. Loreal scales 13–16. Scales around the midbody are 78–100 of which about 13–23 are ventrals. There are 35–41 midventral scales along the trunk. Lamellae (infraproximals in parentheses) under the fingers are: I: 11–16 (2–3), II: 18–22 (5–7), III: 22–26 (6–8), IV: 22–27 (7–11), and V: 19–22 (4–7). Lamellae (infraproximals in parentheses) under the toes are: I: 9–13 (2–3), II: 17–22 (4–7), III: 23–28 (6–10), IV: 25–31 (8–13), and V: 21–25 (5–9). Fingers and toes typically with four, rarely three, lateral rows of scales distally As mentioned above, G. rozei is the most polymorphic species of Gonatodes in terms of male coloration. We have been able to group all male specimens into four different color morphs (Fig. 4) as described below: Morph I: This is the color morph of the holotype. The notable variation observed for this color morph includes the color of the cephalic hood which varies from yellow to orange and the number of ocelli on the sides of the body. Some specimens have only a few ocelli in which case they are always concentrated on the anterior portion of the body. Morph II: In this morph individuals have pale grayish brown background coloration on the dorsal and lateral surfaces of the body, tail and limbs. The body is covered by white, vaguely defined spots and ocelli. The latter have diffused dark gray edges and tend to be located laterally on the anterior portion of the body. The head is slightly darker than the body and it is overlaid with irregular and vaguely defined, pale yellow markings. Limbs have suffused pale markings. Morph III: The dorsal and lateral surfaces of the body and legs are brownish gray to gray, with a few irregular, large, black-edged ocelli located laterally on the anterior portion of the body, most frequently in the scapular region. The head and neck is heavily overlaid with irregular and elongated yellow markings that extend to the gular region. Black suffusions are frequent in the space between the yellow markings. The tail is grayish brown. Morph IV: The dorsal and lateral surfaces of the body are gray and, in contrast to the previous three color morphs, are devoid of any white markings. The head is uniformly dull yellow, including the gular region, which is slightly paler. The tail is brown.
FIGURE 5. A pair of Gonatodes rozei sp. nov. copulating in captivity.
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By far the most common color morph is “I”, which is present in all localities for which several specimens have been obtained. In some localities, like those within Guatopo National Park, almost all male specimens are color morph “I” although color morph “IV” has also been observed at lower frequency in this area. Color morph “IV” has been found in several localities from throughout the distribution of the species and seems to be common in Hacienda El Limón. Color morph “III” has only been recorded in Capaya, Miranda, and Carayaca, Vargas (color morphs “I” and “IV” have also been collected in both localities). Color morph “II” has only been recorded in Carayaca and it is in this locality that all four male color morphs have been observed in sympatry.
FIGURE 6. Map of north central Venezuela showing the collecting localities of the specimens examined of Gonatodes rozei sp. nov.. The holotype is indicated by the star and all other localities by dots. The whole type series was collected within Guatopo National Park, which is delimited by a dashed line. The other three national parks are Waraira Repano (top), Macarao (left) and Laguna de Tacarigua (right).
In females and juveniles the ground color of the body, except ventrally, and the head is brown to grayish brown. There is a pale, creamish brown vertebral stripe that extends from the neck or the occipital region onto the tail, where it becomes poorly defined and disappears on the distal portion. The vertebral stripe has undulating edges, which are typically accentuated by a series of paired, small, diffuse black and white spots. On the sides of the body up to three longitudinal rows of white/pale creamish brown spots are present; of which only one row is conspicuous (spots are white rather than pale creamish brown). The largest pale, lateral spots, are about the size of the pupil. Also, the sides of the body have fine, diffuse, irregular black reticulations; on the limbs these reticulations become more conspicuous. The top of the head might be devoid of any conspicuous markings or might have fine and diffuse black markings forming poorly defined canthal, postocular and parietal/occipital stripes. Irregular and diffuse pale marking might also be present on the top of the head. The whole ventral area tends to paler than the dorsum and in large females the belly and underside of the limbs might be suffused with yellow or a ferruginous tinge. The gular area is typically white or cream with longitudinal, fine, diffuse dark brown stripes. The tail commonly has pale (pale pink, pale brown or white) rings which are more conspicuous ventrally and on the posterior portion of the tail. These rings are usually edged anteriorly by black markings. The rings are much less pronounced on large specimens. Distribution and natural history. The species is found in tropical and premontane humid forests (Ewel & Madriz 1968) on both chains (Serranía del Litoral and Serranía del Interior) of the Cordillera de la Costa Central in
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north central Venezuela (Fig. 6). The species is active during the day and can be commonly observed on trees but close to ground level. It has also been taken from karstic walls outside caves and occasionally individuals have been observed on buildings in areas with large trees near forest habitat. The species has been collected at low elevations (<50 m asl), near the coast, on the western foothills of the Serranía del Litoral (e.g. Carenero and on the road between Chuspa and Higuerote). The locality with highest elevation at which the species has been collected is Taica, Miranda, at about 1000 m above sea level. A couple specimens (MCNC 3733-3734) have been collected on “Pico Naiguatá” Mountain, which exceeds 2700 m above sea level, but the lack of specific locality data prevents us from determining the precise elevation at which these specimens were collected. However, the other localities with more precise information from this mountain are below 800 m above sea level. We also have a few notes on the reproductive biology of G. rozei obtained from individuals kept in captivity by CRB. On August 18, 1966, at about 08h15, a male and female G. rozei that had been kept in captivity for several months were found copulating (Fig. 5). The male was biting the back of the neck of the female and had both his right front- and hind-legs over the dorsum of the female. The tail of the female was raised over the base of the tail of the male. Regrettably, the pair separated as soon as the first picture was shot. Subsequently, the male retreated to the top part of the cage and proceeded to lick his right hemipenis. Remarks. Gonatodes rozei has been known among herpetologists for more than 30 years and it has been frequently collected near the city of Caracas. The name G. rozei was used in the first author’s unpublished PhD dissertation (Rivero-Blanco 1979) but, even though herpetologists have used the name informally over internet gecko forums, to our knowledge it has never appeared in the scientific literature.
Discussion With the description of G. rozei there are now 18 species of Gonatodes known to occur in Venezuela, which represents about 62% of the total species richness in the genus. Moreover, 11 of the 18 species of Gonatodes present in Venezuela are endemic (Rivas et al. 2012 did not consider G. ligiae to be endemic but there are no published records of this species outside Venezuela). Additionally, there are several new species of Gonatodes that are present in Venezuela that remain to be described (Rivero-Blanco 1979; Schargel 2008). The high species richness of Gonatodes in Venezuela is exceptional considering that no other country has more than six species of this widespread genus. It is not clear yet why this genus has diversified so much in north central South America relative to other areas, and we believe this question is worth discussing. Rivero-Blanco (1979) suggested that Gonatodes originated in the Colombian/Venezuelan mountains (Andes and Cordillera de la Costa) and then dispersed from there into other regions (e.g. the Amazon Basin, Middle America). This would have given Gonatodes a longer “time for speciation” (see Stephens & Wiens 2003) to buildup diversity in northern South America. We realize that the high species richness of Gonatodes in north central South America was part of the evidence used by Rivero-Blanco (1979) in the first place to propose the origin of the genus in that region, so species richness cannot be used as corroborating evidence for this hypothesis. Regardless, the phylogenetic trees presented by Gamble et al. (2008) and Schargel et al. (2010) both show that a clade containing two species of Gonatodes that do not occur in north central South America, one of them from the Pacific lowlands of Ecuador (G. caudiscutatus) and the other from the northern part of the Brazilian Shield (G. eladioi); is sister to all other species of Gonatodes. These phylogenetic results are consistent with a more widespread ancestral distribution of Gonatodes, at least within South America (a recent colonization of Middle America does seems supported by phylogenetic data), than what was proposed by Rivero-Blanco (1979). This would suggest that this genus has experienced a higher net diversification rate (i.e., speciation rate minus extinction rate) in north central South America, especially in the Cordillera de La Costa of Venezuela, relative to some of the other regions in which it is found. Rivero-Blanco (1979) also suggested that the fluctuations of the sea level and climatic conditions during the Pleistocene, together with ecological niche conservatism accounts for vicariant speciation events in Gonatodes, consequently increasing the speciation rate in montane species of north central South America. This last hypothesis could be tested once a rigorous framework of temporal diversification within the genus is obtained (see Schargel et al. 2010) in conjunction with ecological niche modeling. Gonatodes rozei is a remarkable species of Gonatodes that shows the greatest level of male color pattern polymorphism in the genus. Up to four different color morphs have been found in a single locality. In recent years,
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within-population discrete color pattern polymorphism in lizards has been the subject of much research (see Sinervo & Lively 1996; Sinervo et al. 2001, 2007; Calsbeek et al. 2002; Sinervo & Clobert 2003; Vercken & Clobert 2008), and it has been shown that this kind of polymorphism tends to be associated to alternative male social/mating strategies (Sinervo & Lively 1996; Sinervo & Clobert 2003). The three main strategies that have been described include: (1) aggressive, territorial males; (2) cooperative males; and (3) sneaker, female mimicking males. These different strategies interact with each other creating a dynamic that resembles a “rock-paper-scissorsgame” as explained by Sinervo & Lively (1996). It is possible that in Gonatodes rozei, as well as in other species in the genus, the different color morphs correspond with alternative male strategies; similar to what has been found in other lizard groups (e.g., phrynosomatids, lacertids). We find two lines of evidence that support this hypothesis. First, one of the male color morphs in G. rozei (morph II) seems to correspond with a female mimicking strategy. Second, within-population discrete polymorphism in male coloration is widespread in the genus and in distantly related species, which seems to rule out population admixture as a global parsimonious explanation for the presence of different male morphs within populations. Further research will be needed on this subject, but it seems clear to us that Gonatodes represents a potentially ideal group to study the evolution of sexual dichromatism and discrete polymorphism, as well as their behavioral correlates. We base this assertion on the following observations: (1) The amount of intra- as well as interspecific variation in coloration seems unparalleled by any other lizard genus (Rivero-Blanco 1979; Schargel 2008; Rojas-Runjaic et al. 2010; this study); (2) Many species are abundant where they occur and easy to observe in the field (Rivero-Blanco 1979); (3) Most species are easy to keep in captivity and individuals will actively use both territorial and courtship displays while captive (Demeter & Marcellini 1981; Schargel unpublished data); and (4) The phylogenetic relationships and taxonomy of Gonatodes has been the subject of much recent study, providing the appropriate evolutionary context for comparative studies (Cole & Kok 2006; Gamble et al. 2008; Schargel 2008; Rivas & Schargel 2008; Rojas-Runjaic et al. 2010; Schargel et al. 2010; Kok 2011; Sturaro & Avila-Pires 2011).
Acknowledgements Research that led to the description of the new species was part of CRB’s Ph.D. dissertation work at Texas A&M University under the supervision of James R. Dixon. For allowing us to examine specimens under their care we are grateful to the late Garth Underwood (BMNH), the late Janis Racenis (MBUCV), the late Abdem R. Lancini (MCN), James R. Dixon, Lee Fitzgerald, and Toby Hibbitts (TCWC), Celsi Señaris, Gilson Rivas and Fernando Rojas-Runjaic (MHNLS). The collecting permits were provided to Gilson Rivas by the Ministerio del Ambiente, Venezuela (permit 01-03-03-3650) through Fundación La Salle de Ciencias Naturales, Caracas. CRB is indebted to the late Mr. Emil Bröckl who prepared the beautiful color plate of the new species more than 30 years ago. WES is particularly grateful to Gilson Rivas for his help in the field and continued collaboration on the taxonomy of Gonatodes. Juan García-Pérez took the color pictures of the holotype and female paratype of the new species. Juan P. Diasparra, Luis A. Rodriguez, César Barrio, Carolina Tosta and Leonardo Salas shared with us pictures of several Gonatodes in life. For reading and providing suggestions and corrections on the manuscript we are indebted to Christian Cox, Gilson Rivas, Fernando Rojas-Runjaic, and Jesse Meik.
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