Cnemidophorus venetacaudus, Arias, Federico, Carvalho, Celso Morato De, Rodrigues, Miguel Trefaut & Zaher, Hussam, 2011

Arias, Federico, Carvalho, Celso Morato De, Rodrigues, Miguel Trefaut & Zaher, Hussam, 2011, Two new species of Cnemidophorus (Squamata: Teiidae) from the Caatinga, Northwest Brazil, Zootaxa 2787, pp. 37-54 : 44-50

Cnemidophorus venetacaudus sp. nov.

( Fig. 4 , 5 )

Holotype. MZUSP 100119 (field number MRT 4714), adult male from Ôlho D’Água da Santa (9 1310" S, 43 2927" W), Parque Nacional da Serra das Confusões, Caracol municipality, state of Piauí, Brazil, elevation 460 m, collected on 5 october 2000 by Hussam Zaher, Miguel Trefaut Rodrigues, and Felipe Curcio.

Paratypes. MZUSP 100115 - 100118 (field numbers, respectively MRT 4644, 4645, 4675, 4694), MZUSP 100120 - 100127 (field 4726, 4754, 4898, 4916, 4946, 4974, 5009, 5011), collected by Hussam Zaher, Miguel Trefaut Rodrigues, and Felipe Curcio, from 4–13 October 2000, and MZUSP 100128 (field MRT 9196), collected by Hussam Zaher, Felipe Curcio, Pedro Nunes and Giovanna G. Montingelli on 22 january 2002; all with same locality data as for the holotype.

Diagnosis. A species of the ocellifer group with granules in the supraorbital semicircles, and no anal spurs in males. Cnemidophorus venetacaudus differs from all the other members of the ocellifer group by the absence of stripes in the dorsum and a high number of femoral pores. In addition, it differs from C. ocellifer , C. nativo , C. mumbuca , and C. jalapensis by having 34–45 (x= 38) femoral pores (24–26, x= 24 in C. nativo ; a maximum of 20 in all other species); 10 longitudinal rows of ventral scales (6–8), 30–32 (x= 31.2) transverse rows of ventrals (29– 32, x= 30.8 in C. nativo , a maximum of 29 in all other species), 31–34 (x= 31.7) scales around tail (a maximum of 30 in all other species), 114–129 (x= 119.5) scales around midbody (91–122, x= 104 in C. jalapensis , a maximum of 117 in all other species), 6 superciliaries (5), 1–2 row of spurs in the heel in males (absent), interparietal narrower than other parietals (wider), humeral region with one row of distinctive enlarged scales (2–4 not so enlarged), and no enlarged scales in temporal region posterior to third subocular (present). Cnemidophorus venetacaudus differs from C. abaetensis by having 34–45 (x= 38) femoral pores (27–31, x= 24), 190–218 (x= 204.8) dorsal scales (210–240, x= 221.8), interparietal narrower than other parietals (wider), second supraocular totally separated from frontal by supraocular granules (second supraocular contacts frontal), four supraoculars (usually 3), dorsal stripe absent (present), stripe in the tail absent (present). Cnemidophorus venetacaudus differs from C. littoralis by having 34–45 (x= 38) femoral pores (28–36, x= 32.6 in C. littoralis ), 190–218 (x= 204.8) dorsal scales (168–191, x= 174.9), interparietal narrower than other parietals (wider), frontonasal never divided (35.6 % of individuals with a divided frontonasal, according to Rocha et al., 2000), second supraocular separated from frontal by supraocular granules (second supraocular contacts frontal), dorsal stripe absent (present), and stripe in the tail absent (present).

Description of Holotype. Measurements: snout-vent-length 83.66 mm; trunk length 40.75 mm; head lengh 19.8 mm; head width 11.24 mm; head height 9.95 mm; tail length 145. 34 mm (regenerated); femur length 15.17 mm; tibia length 12.48 mm; foot length 27.89 mm; humerus length 5.92 mm, and arm length 26.41 mm.

Snout moderately pointed. Rostral large, wider than high, visible from above, separated from frontonasal by the contact between anterior nasals. Anterior and posterior nasals in broad contact at midline through an oblique suture. Nostril rounded in lower part of suture. Frontonasal roughly hexagonal, with almost rounded vertices, contacting posterior nasals and prefrontals. Prefrontals roughly trapezoidal, pentagonal, in broad and straight contact along midline, contacting laterally nasal, loreal and first supraocular. Frontal approximately pentagonal, longer than wide, wider anteriorly, contacting only partially first supraocular and separated from the second and third supraoculars by a row of granules. Two frontoparietals, longer than wide, approximately pentagonal, separated from supraoculars by a row of granules. Five parietals, the interparietal narrow, longer than wide, sub-hexagonal, bordered at each side by much larger parietals. Smaller external parietals, slightly larger than interparietal and diagonally disposed. Occipital scales irregular and variable in size, larger than dorsals. Four supraoculars on each side, second and third largest, and first in contact with loreal, prefrontal, and first and second supraciliaries. Six supraciliaries on each side, third largest and sixth smallest, only first and second supraciliaries in contact with first supraocular, all others separated from supraoculars by a row of granules. Loreal single, large, in contact with posterior nasal, prefrontal, first supraocular, first supraciliary, preocular, first subocular, and third and fourth supralabials. Preocular narrow, higher than wide, in contact with first subocular, loreal, and first superciliary. Three suboculars on each side, anteriormost keeled, approximately pentagonal, in contact with fourth supralabial; second subocular keeled, longer than anterior, approximately rectangular, in contact with fourth, fifth and sixth supralabials; third subocular smooth, slightly shorter than second one, approximately rectangular. A continuous keel runs from preocular to second subocular. Six supralabials on each side. Temporal region with irregular scales, granular centrally, sub-equal, enlarging in size towards eye and ear opening. A supratemporal row with moderately large scales, decreasing in size posteriad. Ear opening large, semicircular, higher than wide. All dorsal and lateral head scales juxtaposed, smooth, except for keeled preoculars and suboculars. Symphysal wider than long, concave anteriorly, convex posteriorly, ellipsoid, contacting posteriorly first infralabials and postsymphysal, forming two wide angles. Postsymphysal single, pentagonal, as long as wide, in contact with first and second infralabials; followed by five pairs of enlarged chinshields. First pair of chinshields the longest, in broad contact along midline, in contact with third infralabials; second, third and fourth pairs separated from infralabials by row of small granules and internally marginated by a series of enlarged scales. Five infralabials on each side, followed posteriorly by series of small scales extending to labial commissure; first infralabials are the smallest. Chin scales irregular in size and shape, diagonally disposed, increasing in size posteriorly. Gular region divided in two areas: anterior one with irregularly shaped, roughly elongate, juxtaposed scales, disposed in roughly oblique and transverse rows from first pair of chinshields, to an imaginary line uniting the lower margin of ear openings; lateral scales largest. Posterior gular region with diminute granules disposed in transverse rows, identical to those on antegular fold. Gular and antegular folds with diminute granules; a series of enlarged mesoptychial scales between the two folds. Scales on nape and sides of neck similar to dorsals. Dorsal and flank scales granular, rounded, smooth, sub-imbricate; 213 scales along a middorsal line from nape to base of tail; 119 scales around midbody (excluding ventrals), 34 scales around tail. Ventrals large, smooth, wider than long, rectangular, imbricate, in 32 transverse rows; 10 transverse rows of ventral scales across midbody. Ventral scales separated from scales on flanks by a row of moderately enlarged scales. Preanal plate with four enlarged scales, the central one largest, contacting one anterior, surrounded laterally by small scales, and two posterior ones that form the lower border of the anal plate. Preanal spurs absent. Thrirty eight total femoral pores in a continuous row with a short gap medially; 18 on right side, 20 on left. Scales on base of tail rectangular, smaller than ventrals, in transverse rows; keeled dorsal and laterally, ventrally smooth. Tail scales becoming gradually longer and narrower from the base to tip; subcaudal scales becoming keeled distally, but less markedly than in dorsals. Limbs with large, smooth, imbricate scales on dorsal aspect of upper arms, antero-dorsal aspect of forearms, antero-ventral aspect of thighs, and ventral aspect of lower legs; elsewhere scales small, granular. Larger scales on upper arms, disposed in longitudinal rows. Forearms with one row of distinctively enlarged scales, wide than long. Dorsal face of arm with one row of enlarged scales. Anterior scales on thigh decreasing in size proximally, with five rows of enlarged scales. Lower legs with two rows of enlarged, hexagonal scales. Ventral aspect of hands and feet granular; one enlarged tubercle at base of pollex. Sub-digital lamellae single; 18 on left and right fourth fingers; 34 on left fourth toe and 35 on right one. Heel with one row of spurs.

Color in preservative. Dorsum, and dorsal parts of limbs light brown. A difuse wide dark-brown, dorsolateral band extends from nostril to groin, marginated inferiorly by a wider light gray band on the lower flanks. Belly, and ventral region of tail bluish white. Head color follows dorsal and lateral body patterns: light brown dorsally and light gray laterally, separated by the dark lateral stripe. Ventral aspect of head bluish white. Ventral aspect of fore and hind limbs brownish white. Dorsal and lateral aspects of tail blue.

Color in life. Dorsal surface of head, body, and limbs light brown. A dark-brown dorsolateral band runs from nostril, across the eye, and reach the groin area. Below it, a light gray area covers all the lateral surface of the head and flanks. Ventral aspect of head bluish white. Paravertebral and lateral stripes absent. Belly and ventral region of tail bluish white. Ventral aspect of fore and hind limbs brownish white. Dorsal aspect of tail bright blue, lateral aspect predominantly bluish green ( Fig. 4 ).

Variation. Based on 12 paratypes.

Head larger (15.41–19.8 mm; x= 16.94 mm), than wide (9.09–11.24 mm; x= 10.01 mm). Head height 7.57– 9.95 mm (x= 8.57 mm). Snout-vent length 63.5–83.66 mm (x= 70.97 mm). Tail length 132.32–145.34 mm, (x= 138.83 mm), 2.1 times longer than SVL. Arm length 5.75–6.5 mm, (x= 6.11mm). Fore limb length 21.76–26.41 mm, (x= 23.91mm). Tibia length 10.45–12.48 mm, (x= 11.58 mm). Thigh length 12.15–15.17 mm, (x= 13.26). Foot length 21.8–27.9 mm, (x= 24.0 mm). Hind limb, 1.88 time longer than foot. Hind limbs length 39.66–55.54 mm, (x= 48.72 mm).

There is no sexual dichromatism in adult pattern. Males have spurs in heel. MZUSP 100121 has seven superciliars. Variation in other meristic characters is summarized in Table 1 .

Etymology. The specific epithet, veneta, is a Latin adjective meaning ‘‘bluish,’’ and the Latin superlative suffix caudus, meaning ‘‘tail.’’ The name ‘‘bluish tail’’ is an allusion to the characteristic blue coloration of the tail of this species.

Natural history and distribution. The Parque Nacional da Serra das Confusões (PNSC) is located in the southeastern part of the state of Piauí (08°32’– 09°16’S, 43°15’– 43°51’W) and was created in 1998 to protect an area of 5024 km ², between the towns of Caracol, Guaribas, Cristino Castro, and Tamboril do Piauí ( Fig. 1 ). All the area of the National Park is enclosed within the drainage of the Rio Parnaiba, with altitudes ranging from 450 to approximately 700 m ( Rodrigues et al., 2001; Bour and Zaher, 2005). Most of the area of the park corresponds to an extensive arenitic plateau, the “Chapada dos Gerais” (locally known as “Serra Grande”), dissected by intermittent drainages ( Rodrigues et al., 2001; Bour and Zaher, 2005). The borders of the plateau are deeply dissected and characterized by ruiniform rocky outcrops with sandy soils originated from the erosion of Serra Geral, especially on lower areas. The climate is tropical semi-arid and most of the region is covered by xeromorphic and thorny plants with deciduous leaves. As usual in the Caatinga, cactuses are especially abundant. Although most of the area is dominated by the Caatinga, some scattered Cerrado-like trees with a leathery bark trees occur near crevices in the plateau borders, especially near sandy soils among the rock outcrops. Further information on the area can be obtained in Rodrigues et al. (2001) and Bour and Zaher (2005). We collected at Toca da Cabocla, Canto Verde, and Morrinhos on the Serra Grande plateau; all covered by a highly dense Caatinga vegetation dominated by Leguminosaeae and Euphorbiaceae with trees reaching up to 6–7 meters high ( Fig. 6 and 7 ). We also sampled at the Ôlho D’Água da Santa, in the lowland areas with sandy soils near the plateau border and at Lagoa do Jacú, a lowland area covered by an evergreen Caatinga vegetation.

Cnemidophorus venetacaudus was collected only at Olho D’Agua da Santa in an area characterized by sandy soils with arenitic outcrops near the plateau border ( Fig. 8 ). In this area it was observed sintopically with C. confusionibus which is widely distributed in the PNSC. Specimens emerged from their nocturnal refuges in suny days, around 9am, and remained active until the end of the day. They usually took refuge under rocks, fallen trunks, piles of debris, or small holes in the ground. Most specimens were observed when foraging among tufts of Caatinga vegetation in white sandy soils at the hotest part of the day. Eventually they were spotted crossing rocky areas. Cnemidophorus confusionibus is much more abundant than its congener in the area.

Other species obtained in the region were: the tropidurids Stenocercus squarosus , Tropidurus oreadicus , and Tropidurus semitaeniatus , the leiosaurid Enyalius bibroni , the hoplocercid Hoplocercus spinosus , the gymnophthalmids Calyptommatus confusionibus, Colobosaura mentalis, Micrablepharus maximiliani , and Procellosaurinus erythrocercus , the teiids Ameiva ameiva , and Tupinambis merianae , the skink Mabuya heathi, the phyllodactylid Phyllopezus pollicaris , and the gekkonid Hemidactylus brasilianus . Up to now, Cnemidophorus confusionibus is know only from PNSC. We have seen no specimens of C. venetacaudus other than the type series but one of us (MTR) has a copy of a picture taken in 1989 by Ivan Sazima after a specimen obtained at Boqueirão Grande, municipality of Recanto do Buriti, Piauí, about 120 km NE from the type locality.

Figures

FIGURE 1. Distribution of Cnemidophorus confusionibus and Cnemidophorus venetacaudus in the Parque Nacional da Serra das Confusões (PNSC), Piauí, Brazil. Black circles = C. confusionibus; black squares = C. venetacaudus. Localities: 1) Ôlho D’Água da Santa, 2) Morrinhos, 3) Toca da Cabocla, 4) Canto Verde, and 5) Lagoa do Jacú.

FIGURE 4. Cnemidophorus venetacaudus, Olho D´Água da Santa, Parque Nacional da Serra das Confusões, Piauí, Brazil. Photo: Miguel Rodrigues.

FIGURE 5. Cnemidophorus venetacaudus, holotype, MZUSP 100119, adult male. A) dorsal view of the head; B) lateral view of head; C) ventral view of the head; D) preanal plate and femoral pores.

FIGURE 6. Habitat of Cnemidophorus confusionibus at Morrinhos in the Serra Geral, Parque Nacional da Serra das Confusões, Piauí, Brazil.

FIGURE 7. General aspect of a dense and thorny Caatinga, habitat of Cnemidophorus confusionibus, near Canto Verde, Parque Nacional da Serra das Confusões, Piauí, Brazil.

FIGURE 8. Habitat of Cnemidophorus venetacaudus and Cnemidophorus confusionibus at Ôlho D´Água da Santa, Parque Nacional da Serra das Confusões, Piauí, Brazil. Both species occur sintopically at sandy areas among rock outcrops.