Tropidurus panstictus, MYERS & DONNELLY, 2001

MYERS, CHARLES W. & DONNELLY, MAUREEN A., 2001, Herpetofauna Of The Yutajé - Corocoro Massif, Venezuela: Second Report From The Robert G. Goelet American Museum-Terramar Expedition To The Northwestern Tepuis, Bulletin of the American Museum of Natural History 2001 (261), pp. 1-1 : 1-

Tropidurus panstictus , new species Figures 44A , 45–48

HOLOTYPE: EBRG 3130 (field no. CWM 19795), an adult male from south end of Cerro Corocoro , 1220 m (5°42̍N, 66°10̍W), Amazonas, Venezuela; collected March 1, 1995, AMNH –TERRAMAR Expedition. See locality 2 on map (fig. 1).

PARATOPOTYPES: AMNH 147040–147045, EBRG 3128–3129, 3131–3132, from same locality as holotype, collected February 28– March 1, 1995, AMNH –TERRAMAR Expedition.

PARATYPES: AMNH 147046 , EBRG 3133– 3134 , from above Yutaje´ , Río Corocoro, 180 m (5°37̍N, 66°07̍W) ; collected March 2, 1995, AMNH –TERRAMAR Expedition. See locality 3 on map (fig. 1) .

ETYMOLOGY: The species name panstictus is an adjective derived from the Greek pan­ (all, all over) + stiktos (dappled, spotted, punctured), in allusion to the profuse speckling and spotting over the head, body, and limbs of adults.

DIAGNOSIS: A large Tropidurus having several tufts of elongate, spinous scales on the neck; complete gular and antegular folds; anteriorly imbricate head scales; small, slightly imbricate, acutely pointed, thornlike body scales; and a middorsal crest from rear of head onto the tail.

Tropidurus panstictus most nearly resembles T. lumarius , from which panstictus differs in larger size and a different color pattern, which is much lighter and which includes profuse pale speckling in adults (see later, under Comparison with Tropidurus lumarius ). Tropidurus panstictus differs from other spiny­necked tropidurines in the same way that T. lumarius does (Donnelly and Myers, 1991: 31–32). We provide a key to Venezuelan tropidurines following the Remarks section.

SIZE AND PROPORTIONS

Head large, head length (measured obliquely from tip of snout to angle of jaw) 26–30% of SVL; head longer than wide and wider than high, wider than neck; neck narrower than body. Snout rounded to broadly rounded in dorsal view, not projecting over mouth. Body wider than deep. Limbs long and slender, pentadactyl; relative finger and toe lengths 4> 3> 2> 5> 1. Tail 1.6–2.1 times SVL; tail becoming slightly vertically compressed and then rounded toward end. Four adult males with maximum snout–vent length of 119 mm (96–119 mm, x = 108.3 mm, SD = 9.6). One adult female 93 mm SVL, five juvenile males 62–94 mm SVL, two juvenile females 66–71 mm SVL, and two unsexed juveniles 40–54 mm SVL.

SQUAMATION, POCKETS, AND FOLDS

HEAD (fig. 44A): Interparietal large, roughly triangular, wider than long or longer than wide; posteriorly bordered by 1–3 rows of small smooth or rounded scales separating the interparietal from small pointed scales on rear of head; laterally in contact mainly with irregularly shaped smooth scales. Scales of interocular and frontonasal region irregularly shaped, usually smooth (with sensory pits), occasionally a few scales keeled; weakly imbricate anteriorly; 2–3 rows between circumorbital series (three in holotype). Circumorbitals mainly in 2 rows, inner row with largest scales, anteriormost and especially posteriormost scale in inner (and sometimes outer) row often resembling adjacent supraoculars in being longer than wide. Three or (usually) four large supraoculars (4/ 3 in holotype). Superciliaries longer than high, in three stacked rows; scales in middle row largest; superciliaries forming a laterally or dorsolaterally projecting crest extending beyond orbit.

Nasals separated from rostral and first supralabial by 1–2 scales. Rostral separated from internasals by 1–2 rows of postrostral scales. Internasals about 15–23 in 3–4 vague rows (holotype, 18 scales in 4 rows). Super­ ciliary series terminates in a single large canthal; canthal separated from nasal by 1–2 scales. Loreal region with 6–13 small to moderate­sized smooth scales with pits. Lorilabials in 3–6 rows. Enlarged median suboculars 4–6; suboculars keeled (with sensory organs on keels). Temporal region with moderate­sized keeled or pointed scales, which imbricate anteriorly. Rostral much wider than high, little higher than adjacent supralabial. Supralabials 4–6, usually 4/4 (as in holotype).

Mental scale projecting slightly posteriorly beyond anterior margins of adjacent infralabials. Postmental series not well defined. Infralabials 5–7, usually 5/5 (as in holotype, which has second infralabial on right partially divided). Gular scales smooth, increasing in size anteriorly and laterally; lateral gulars laterally imbricate; anterior gulars anteriorly imbricate; medial posterior gulars imbricate posteriorly, then grade into conical and pointed granules, with pointed granular scales to either side.

TYMPANUM: Ear canal moderately deep, opening higher than wide; a tuft of 4–6 large pointed scales at anterior margin; usually two tufts of large pointed scales near posteroventral margin, sometimes merged into an obliquely elongated larger tuft. Internal rim of ear canal anteriorly lined with small smooth scales; dorsal, ventral, and posterior rim lined by smaller, smooth or weakly keeled, elongate scales.

NECK: Nape with anteriorly imbricate small pointed scales (large granules). Side of neck with pointed granules, anterior ones dorsally imbricate, becoming posteriorly imbricate caudad. Two tufts of elongated spiny scales more or less in line with upper edge of ear opening; spines in anteriormost tuft largest; posteriormost tuft situated at terminus of oblique neck fold.

POCKETS AND FOLDS: Terminology following Frost (1992: 25–27): Antegular fold complete (faint in smallest juvenile), although sometimes interrupted medially by longitudinally raised ridge of granules extending posteriad from throat; antegular fold overlapping or lying just anterior to the gular fold. Antegular fold continuous with oblique neck fold, which terminates in posteriormost tuft of scales on side of neck. Lateral mite pocket present, under junction between antegular and oblique neck folds. Gular fold complete, its lateral mite pocket continuing under the antehumeral fold. Scales lining folds not (or but little) reduced in size, except for tiny smooth granules in mite pockets. Rictal fold present. Dorsolateral fold present, anteriorly continuous with antehumeral fold; granular scales on dorsolateral fold elongate and pointed, somewhat larger than other body scales. Weak ventrolateral fold present, its scales little larger than other body scales. No mite pockets in axilla or groin.

BODY: Middorsal crest of laterally compressed, long pointed scales directed posterodorsally, starting about 3–7 scales behind interparietal and continuing onto tail; crest scales on body about 68–89 (x = 76.2), usually decreasing in height posteriorly and then increasing somewhat on base of tail. Middorsal crest present on all specimens, being best developed in adult males and weakly de­ veloped in small juveniles, in which enlarged crest scales are prominent but are not elevated.

Body to either side of middorsal crest with slightly imbricate, acutely pointed scales directed posterodorsally. Paravertebral scales (from posterior edge interparietal to level of posterior margin of thigh) 153–175 (x = 169.7). Scales around midbody 143–164 (x = 157.0).

Ventral scales larger than dorsals and smooth; ventrals somewhat irregularly shaped, those on anterior venter usually posteriorly pointed and imbricate, often becoming quadrangular and subimbricate on posterior belly, in wavy transverse rows only; 30–36 scales across chest (x = 32.2); 95–116 transverse rows from gular fold to vent (x = 108.5). Umbilical scar still present in smallest juvenile (40 mm SVL).

LIMBS: Dorsal surface of upper arm with moderate­sized, imbricate, acutely pointed scales, much larger than granular body scales. Dorsal surface of forearm with larger, imbricate scales, weakly to sharply keeled, slightly mucronate; scales on lateral side of forearm with mucrones elevated and acutely pointed. Elbow scales smooth. Ventral side of arm with moderate­sized, imbricate, smooth scales, sometimes faintly mucronate. Top of hand with smooth (some slightly mucronate) imbricate scales, some scales becoming keeled distally on fingers; palm with either smooth or weakly keeled scales, tending to be distally elevated and mucronate. Subdigital lamellae single, tending to be bicarinate on fingers I and II, becoming tricarinate on fingers III–V, distally changing to carinate. Subdigital lamellae of fourth finger 23–30 (x = 26.1, SD = 2.04).

Dorsal and posterior thigh with small pointed scales not much larger than granular body scales; raised scale points (and direction of imbrication) projected posteriorly on top of thigh, dorsally on posterior thigh. Anteroventral thigh with larger smooth scales (some slightly mucronate) imbricating toward knee; ventral thigh with smooth scales posteriorly imbricate. Lower leg scales keeled and mucronate on upper surfaces, smooth on ventral side, all imbricate toward foot. Knee scales smooth, smaller than adjacent dorsal or ventral scales. Dorsal scales of foot proximally small, essentially smooth, distally becoming larger, keeled, mucronate. Sole with smooth, slightly mucronate scales. Subdigital lamellae with carination similar to that of fingers. Subdigital lamellae of fourth finger 31–39 (x = 34.8, SD = 2.26).

TAIL: Enlarged middorsal crest scales continuous from body crest, declining in size posteriorly; distinct on anterior third to half of tail. Dorsal and lateral caudal scales posterodorsally imbricate or subimbricate, acutely pointed on base of tail, becoming weakly mucronate distally. Subcaudal scales posteriorly imbricate, smooth, becoming weakly keeled toward tip of tail.

COLORATION

In life (or shortly after death, fig. 45), 27 head of adults with black, light yellow, yellowish brown, or greenish markings, including a small to large pale spot on the parietal in all. A variably configured and broken black nuchal collar and a V­shaped scapular band (posterior to antehumeral folds). Dorsal surfaces of body greenish gray or light brown, with several ill­defined blackish blotches (posterior to scapular band) visible on middorsum of the lighter specimens. Dorsum and sides overall densely and rather uniformly speckled with small spots and dots of pale tan, pale yellow, or pale green.

Limbs colored like dorsa, with black or grayish brown bands on the paler ground col­ or; bands on forelimbs tending to be darker and better defined than those on hind legs. Dark tail bands on the lighter ground color.

Underside of head with black markings on variable ground color of pale green, or bluish gray, or yellow on chin and orange on throat. Ventral surface of body and limbs bluish white, with an ill­defined but conspicuous suffusion of orange along ventrolateral sides of venter and under tail. Iris brown, tongue and mouth lining unpigmented.

A juvenile paratopotype (fig. 47) had a grayish head with brown markings, promi­

27 Color in ‘‘life’’ is based on transparencies and fieldnote descriptions made by daylight, from dead or stunned upland paratopotypes that had been recently collected with.22­caliber dustshot. A few lowland paratypes reached camp after dark and were only photographed (fig. 46).

31333, AMNH 147046 ♀ (lower).

nent black nuchal and scapular markings, and a light brown body with darker brown, round spots; the limbs and tail were light brown with darker brown bands.

In preservative, dorsal ground color grayish brown to blackish, with numerous light spots and flecks scattered over body, except light flecking inconspicuous in smaller juveniles. Collar and cape often emphasized by light internal spots and edging of light markings. Three to five irregular dark middorsal blotches on body posterior to scapular band, sometimes (especially in juveniles) with irregular smaller blotches on sides; dorsal markings often vague. Light interorbital bar (anterior to supraocular scales) present in all, distinct in most (V­shaped in one); a less distinct light bar across snout discernible in most. A light triangular to round, small to large parietal spot, usually distinct. Light spots or one or two light lines from eye to upper lip; a dark­edged light stripe or a few light lines on side of head from eye to ear; upper lip black with light spots (still showing yellow or light blue color in a few) distinct or vague; lower lip spotted black or gray.

Larger specimens with large black spot on base of throat, this spot smaller or absent in others. Underside of head rather densely marked with gray lines or spots tending to radiate forward and outward from black spot (when present) or from base of throat. A midventral dark­edged, light gular line in some specimens, extending from middle of throat to base.

Forelimb, especially lower arm, with distinct black bands and narrower light interspaces. Hind legs usually less distinctly banded. Venter and undersides of limbs and tail cream, often with light gray suffusion. Tail bands distinct in smaller individuals.

HEMIPENIS

The right hemipenis of a paratopotype (AMNH 147041), which had been partially everted in the field, was detached from the specimen and softened in a solution of KOH. After removing as much of the major retractor muscle as possible, the organ was inflated with red­dyed petroleum jelly. Each lobe had to be manually everted separately, and each lobe ruptured at its delicate apex. The complete eversion otherwise was successful, as shown in figure 48.

The hemipenis is tiny considering the size of the adult male (119 mm SVL). When straightened from its curved position, the organ measures about 11 mm from the base to the tip of one lobe. It is divided for about half of its length. The sulcus spermaticus bifurcates proximal to the crotch, and the sulcus branches diverge in centrolineal orientation and extend apparently to the tips of the lobes. The basal stalk of the hemipenis lacks ornamentation; there are thin lateral alae on the sides of the stalk, extending from about halfway up the stalk and terminating at the base of each lobe.

The lobes are nearly fully calyculate, from shortly above the base of each lobe, with the calyces decreasing in size distally from the large basal calyces. The calyculate areas are confined to the lobes and are widely separated across the nude crotch.

COMPARISON WITH TROPIDURUS LUMARIUS

Tropidurus panstictus is most similar to T. lumarius from Cerro Guaiquinima, about 300 km east of the Yutaje´–Corocoro massif, on the other side of the Sierra de Maigualida. Tropidurus panstictus is a larger species: Four adult male panstictus average 108.3 mm SVL (96–119 mm), compared with a mean of 88.5 mm (76–100 mm) for four adult male lumarius . One adult female panstictus measured 93 mm SVL, compared with a range of 76–79 mm (x = 77.1) for five adult female lumarius . The difference in SVL appears to be correlated with a relatively stockier head and body in T. panstictus .

Apart from size, it is hard to find consistent differences in the morphology of these two lizards. Differences seen when comparing one individual with another mostly disappear when intrapopulational variation is considered. For example, when comparing heads of the holotypes (fig. 44), there are visible differences in the disposition of spinous scales on the anterior ear margin, and in alignment of the two spiny tufts on the neck, but these traits are variable in each species. The elongate spines on the granular neck and body scales seem to us to be longer in lumarius than in panstictus , but any difference would be tediously difficult to quantify. One difference, although not an absolute one, involves the nature of the tiny scales in contact with the rear margin of the large interparietal. In T. lumarius , the interparietal usually is in contact with small pointed scales anterior to the middorsal crest, but sometimes a row of small smooth scales intervenes. In T. panstictus , there usually are 2–3 rows of small smooth scales separating the interparietal from the small pointed scales, but sometimes there is only one such row, as in lumarius . Such a difference, not detectable in the draw­ ings (which cannot show elevated points or mucrones on granular scales at the magnification drawn), would seem both biologically and taxonomically insignificant.

Differences in living coloration are pronounced. Tropidurus lumarius is essentially a black lizard, with small yellowish spots and dots, which are frequently coalesced to form ill­defined transverse bars or rows of spots on the body and tail or narrow crossbars on the limbs. Adult males have golden yellow patches on the posterior belly, preanal area, and undersides of thighs, whereas females have a pink wash in the same area.

Tropidurus panstictus differs from the above in having a lighter ground color and (especially in adult males) a profuse dappling of small light spots and dots that do not coalesce to form bars or rings (figs. 45, 46). Rather than golden yellow ventral patches as in lumarius , adult male panstictus are suffused with orange ventrolaterally and under the tail. Some specimens of panstictus have dark dorsal spots and other dark markings not observed in lumarius .

Both species share variable but similar black nuchal and scapular markings, but these tend to be obscured in Tropidurus lumarius and more prominent in T. panstictus . Direct comparison of the hemipenes suggests that the organ of T. panstictus (fig. 48) is virtually identical to that of T. lumarius (Donnelly and Myers, 1991: fig. 18), although the latter organ is less well prepared. The earlier published drawing for T. lumarius shows only representative calyces on the lobes, which prove to be incompletely evert­ ed; the calyculate areas resemble those in T. panstictus (fig. 48).

REMARKS

We described Tropidurus lumarius from 14 specimens that we collected on the summit of Cerro Guaiquinima in 1990 (Donnelly and Myers, 1991) on an expedition sponsored by the Fundación para el Desarrollo de las Ciencias Físicas, Matemáticas y Naturales (FUDECI); this expedition included different groups of scientists working on various projects during different times, with no coordination between groups. We were not informed that a German group had been sched­ uled to work on amphibians and reptiles before us; later, we were given reason to believe that their interests were not systematic. We were unaware that a professional herpetologist was involved with the German effort, and we certainly made a mistake in not pressing for more particulars on the German party and in not trying to make contact—we probably missed a chance at fruitful collaboration. But we thought no more about it until we saw in late March, 1991, their collection report that had been published a month earlier (Mägdefrau et al. 1991). We were surprised by their report—as they doubtless also were when our own report appeared several months later on June 28 (Donnelly and Myers, 1991). A short paper by Mägdefrau (1991) appeared a few days after that, with the description of Plica nigra , a junior synonym of T. lumarius (synonymy by Frost, 1992: 5). This hapless duplication of effort, and a comparison of collection results, is discussed in a postscript to our 1991 paper. The only reason for bringing it up again emanates from insinuations made recently by Gorzula and Señaris (1999: 153).

Among other things, these authors complained that Gorzula had collected the first specimens of Tropidurus lumarius / nigra six years before the 1990 FUDECI expedition, and that unnamed persons in FUDECI were aware that he had been planning to describe the new lizard. Gorzula and Señaris (1999: 153) asserted that ‘‘Certainly by late 1990, staff of both the AMNH and the ZSM were aware of the series of [Gorzula’s] specimens collected in 1984 and 1985.’’ This statement is fabricated! We did not learn of Gorzula’s earlier collection of this lizard on Cerro Guaiquinima until much later, long after the 1991 publications (Mägdefrau et al., 1991; Mägdefrau, 1991; Donnelly and Myers, 1991), and we have no reason to believe that our German colleagues knew of it either. In 1995, Gorzula first complained about the matter in a letter to Myers; in that letter, Gorzula did not mention FUDECI, but twice laid the blame on unidentified persons in TER­ RAMAR, where ‘‘I spent a whole morning giving them maps of Guaiquinima and telling them where and what I had collected’’ (letter, Gorzula to Myers, August 24, 1995). In response, Gorzula was advised that (1) it had been not a TERRAMAR but a FUDECI­sponsored expedition, and that we had had no association with TERRAMAR in 1990; (2) his information had not been passed on to us (by either institution); and (3) that his prior manuscript name would have been honored had we known about it. 28 There is much water under such bridges.

Tropidurus panstictus is not endemic to Cerro Yutaje´, but occurs also on neighboring Cerro Guanay (Myers and Donnelly, in progress).

Figures

Fig. 44. Dorsal, lateral, and ventral views of heads of adult male holotypes. A: Tropidurus panstictus, new species (EBRG 31303, 111 mm SVL). B: Tropidurus lumarius Donnelly and Myers (AMNH 136176, 98 mm SVL). Scale line = 10 mm for both.

Fig. 45. Tropidurus panstictus, new species. Coloration of adult males before preservation. Top: Holotype (EBRG 3130) in dorsolateral view. Bottom: Dorsal view, left to right, EBRG 3130 (holotype), AMNH 147041, 147042 (paratopotypes).

Fig. 46. Tropidurus panstictus, new species. Dorsal and ventral views of lowland paratypes, EBRG

Fig. 47. Tropidurus panstictus, new species. A juvenile paratopotype (AMNH 147045, 40 mm SVL). Compare with color pattern of adults (figs. 45, 46).

Fig. 48. Hemipenis of Tropidurus panstictus, new species Right organ of AMNH 147041 (paratopotype, 119 mm SVL), in sulcate and asulcate view, Χ7.9.