Euspondylus auyanensis, Myers & Fuenmayor & Jadin, 2009

Myers, Charles W., Fuenmayor, Gilson Rivas & Jadin, Robert C., 2009, New Species of Lizards from Auyantepui and La Escalera in the Venezuelan Guayana, with Notes on ‘‘ Microteiid’ ’ Hemipenes (Squamata: Gymnophthalmidae), American Museum Novitates 3660, pp. 1-32 : 3-12

publication ID	https://doi.org/ 10.1206/657.1
persistent identifier	https://treatment.plazi.org/id/C57A878A-6605-FFA0-3B86-089F0A76FD91
treatment provided by	Carolina
scientific name	Euspondylus auyanensis
status	sp. nov.

Treatment

Euspondylus auyanensis , new species

Figures 1–7 View Fig View Fig View Fig View Fig View Fig View Fig View Fig

Anadia species : Gorzula (1992: 276). Ayarzagüena et al. (1992: 127). Myers (1997: 4). Mentions of an undescribed species discovered by Gorzula on Auyantepui.

Anadia species b: Gorzula and Señaris (1999: 115–117), brief description of Gorzula’s lost specimens from Auyantepui.

Anadia species : Myers and Donnelly (2008: 88–89) View Cited Treatment , discussion of foregoing report and in-press mention of rediscovery of species by Renaud Boistel.

HOLOTYPE: Muséum National d’Histoire Naturelle ( MNHN) 1999.4799, an adult male from the summit of Auyantepui, [near] ‘‘ El Libertador,’’ 4 2325 m, Estado Bolívar, Venezuela, collected by Renaud Boistel in November or December, 1998.

ETYMOLOGY: From the tepui Auyán + - ensis (- e), a Latin adjectival suffix indicating origin or place.

DEFINITION AND DIAGNOSIS: A small lizard (adult ³ 60 mm SVL) of moderate build; tail less than twice body length. Tongue bearing imbricate scalelike papillae; numerous pairs of chevron-shaped infralingual plicae. Hemipenis bilobed, with chevron-shaped folds bearing comblike rows of spinules.

4 ‘‘El Libertador’’ refers to a bust of Simón Bolívar, which was placed near the southern edge of the Auyán summit in 1956, by an expedition from the Universidad Central de Venezuela ( Lindorf, 2006: nt. 18). It is a wellknown place name that is shown on maps in Dunsterville (1965) and Steyermark (1967); see Myers and Donnelly (2008: 27).

Head scales smooth. Paired prefrontals present. Supraoculars separated from eyelids by a complete superciliary series; anterior superciliary large, sometimes expanded dorsally to fuse with small presupraocular. Interparietal extending farther posteriad than parietals. Nasal scales separated by rostral and undivided frontonasal. Loreal large, in contact with supralabial; frenocular absent(?), seemingly fused with loreal (but see comment under Remarks). Lower eyelid with a row of about six somewhat enlarged, semitranslucent palpebrals. Tympanum recessed, lightly pigment- ed. Single postmental scale followed by two pairs of genials in contact with labials; genials followed by large medially separated postgenials. No anterior gular crease at ears and no guttural fold across throat; collar fold conspicuous. No enlarged paramedian gulars.

Dorsal scales keeled, rectangular or slightly rounded posteriorly, in transverse rows only. Lateral scales small, smooth; lateral fold absent. Ventrals smooth, rectangular, subimbricate, forming both transverse and longitudinal rows. Preanal scales in two rows. Femoral pores and preanal pores on same line. Limbs pentadactyl, all digits clawed; subdigital lamellae mostly single; base of pollex with a weakly enlarged thenar scale. Dorsal and lateral caudal scales rectangular, keeled only on base of tail, smooth distally. Subcaudals smooth, wider than dorsal caudals, disposed in two rows of large squarish scales distally. Caudal scales in transverse rows one-scale wide all around tail; dorsal caudals in transverse rows only, ventral caudals in both transverse and longitudinal rows.

The generic affinities of ‘‘ Euspondylus ’’ auyanensis are uncertain, but the combined characters above and the distinctive coloration (figs. 1, 3) separate it from all other named microteiids. It also is a larger lizard than other Venezuelan species currently assigned to Euspondylus . See Comparisons.

DESCRIPTION OF HOLOTYPE

The undissected male holotype is about 152 mm in total length (59.6 mm SVL + 92 mm tail length [tip missing]). It is sexually mature as judged by the well-developed hemipenes and swollen femoral pores.

(MNHN 1999.4799). Scale lines 5 5 mm.

Measurements, some scale counts, and relevant methodology are provided in table 1.

HABITUS AND PROPORTIONS ( FIGS. 1–3 View Fig View Fig View Fig ): Snout attenuate, not flat on top. Head length 24% of SVL, 1.6 times longer than wide, 1.3 times wider than high; head little wider than neck (which is slightly overinflated with preservative). Neck long, 63% of head length, 33% of trunk length. Snout-axilla length 104% of trunk length, 47% of SVL. Body wider than deep. Tail ventrally flattened proximally, otherwise nearly cylindrical. Limbs pentadactyl, all digits clawed (lacking left forelimb). Forelimb 30% of SVL, 67% of trunk length; hind leg equal to trunk length, 45% of SVL; appressed limbs widely overlapping (toe IV extending past elbow).

TONGUE AND DENTITION: (To avoid damage to the unique specimen, the mouth was gently pried only partly open, allowing minimal description.) Tongue lanceolate; gray over visible dorsal surface well onto fork (tips unpigmented); except for tips, fork also gray below; rest of visible tongue nearly unpigmented ventrally. Upper surface of tongue behind fork covered with scalelike papillae (proximal part of tongue not examined), which extend onto ventrolateral sides of tongue; papillae not arranged in rows. Raised medioventral side of tongue with median groove, which extends anteriorly through numerous pairs of thin, oblique, anteriorly converging (chevronlike) infralingual plicae; anterior pair of infralingual plicae much larger than those following.

Anterior maxillary and dentary teeth nearly conical in profile; anterior teeth slightly recurved, losing curvature and becoming slightly larger and weakly bicuspid posteriorly (with a very small cusp on anterior face of tooth).

SCUTELLATION: All head scales smooth. Rostral plate much wider than deep, laterally in contact with nasal and first supralabial, dorsally in contact with large frontonasal. Frontonasal pentagonal, with nearly straight anterior edge and apex on posterior edge. Paired prefrontals in broad contact medially. Frontal weakly hexagonal, concave laterally. Paired frontoparietals with long medial suture, in contact with interparietal, parietals, and two posterior supraoculars. Three or four large supraoculars: three supraoculars on left side preceded by a small presupraocular; four supraoculars on right side resulting from apparent fusion of presupraocular with the first superciliary (or ‘‘presuperciliary’’). Interparietal longer than wide, with anterior apex, weakly concave posteriorly. Parietals not as wide as interparietal, not extending as far posteriad as interparietal. Three dorsal occipitals (postparietals), the medial one smallest. Two postoccipitals larger than other dorsal neck scales.

Nostril slightly anterior of center in nasal scale, which is divided below naris on right side only. Nasal scale in broad contact with rostral anteriorly and with loreal posteriorly. Loreal large, situated between a prefrontal and second supralabial, posterodorsally in broad contact with first superciliary. Frenocular absent (seemingly fused with loreal, but see under Remarks). One preocular and several irregular postoculars. Two (left) or three elongate superciliaries posterior to large first superciliary; one (right) or two small azygous scales inserted between superciliaries and penultimate supraocular. A very elongate subocular, smoothly (without pronounced angularity) approaching lip above supralabials 4–5, which are very low and in little more than point contact. Seven supralabials on each side (posteriormost very small).

Eight large ciliaries along upper eyelid; about 6 smaller ciliaries along edge of lower eyelid. Edges of eyelids darkly pigmented, brown pigmentation on eyelids otherwise sparse. Semitranslucent scales on lower eyelid include a line of 4–7 somewhat enlarged palpebrals below ciliaries; lower palpebral granules concealed by folding.

Temporal scales juxtaposed, smooth, with rounded surfaces, largest above, progressively smaller ventrad. Ear opening a vertical ovoid, edged all around with pebblelike granular scales; tympanum recessed, lightly pigmented.

Underside of head with four infralabials on each side. Large mental followed by large postmental in lateral contact with first infralabials. Two pairs of genials, each pair in median contact, in contact with infralabials 1– 3 laterally. Two pairs of side-by-side, large postgenials, each pair in contact with a member of the second pair of genials; lateral member of each pair of postgenials in partial contact with third infralabial. Small to medium-size gular scales with slightly rounded surfaces, subimbricate. Gulars posteriorly becoming larger and arranged in transverse rows, culminating in collar row of about eight scales. Medial collar scales largest, overhanging collar fold of small scales. Side of neck between ear and collar pebbled with subequal, rounded juxtaposed scales.

Dorsal scales on neck subimbricate, irregularly shaped to posteriorly rounded, some become weakly keeled toward forearms. Dorsal body scales keeled, weakly imbricate, longer than wide—rectangular or with slightly rounded posterior ends—in transverse rows only. About 10 large keeled scales across transverse rows at midbody, each transverse row of dorsals laterally becoming 1–2 rows of much smaller scales (fig. 4); the small lateral scales are smooth and juxtaposed.

Ventral scales smooth, quadrangular, roughly 1.3–1.6 times wider than long, barely subimbricate; in 9–10 longitudinal rows at midbody (including 1–2 small ventrolateral plates) and 24 transverse rows between collar and preanal scales. Ventrals much wider than dorsals.

Three anterior preanal scales, the median one much larger than the lateral ones (fig. 5). Five marginal preanal scales anterior to vent, the three middle ones much larger than the lateral ones. Adult male with 15/18 femoralpreanal pores; pore scales slightly swollen, in contact, forming an uninterrupted series from each leg onto preanal area, where the left and right sides are separated by one poreless scale.

Dorsal and lateral caudal scales rectangularly longer than wide, strongly to weakly keeled on base of tail and smooth distally. Subcaudals smooth, about same length as dorsals but larger, and wider than long on base of tail, becoming disposed in two rows of large squarish scales distally. All caudal scales subimbricate, with straight edges, in transverse rows one-scale wide all around tail, the first few rows ventrally narrowed behind vent.

Dorsal surfaces of arm with large, smooth imbricate scales, obtusely pointed on upper arm, tending to have broadly rounded edges on lower arm. Ventral side of upper arm with small, smooth, rounded subimbricate scales; ventral side of lower arm with large rounded or obtusely pointed, smooth imbricate scales.

TABLE 1 Measurements (in mm) and Scale Counts of Holotype of Euspondylus auyanensis , New Species

Hind limbs with large, mostly obtusely pointed imbricate scales that are weakly striated or keeled dorsally and smooth ventrally. Posterior and posterodorsal surfaces of thigh pebbled with small, round, and raised juxtaposed scales.

Small to moderately large scales atop hands and feet. Supradigital scales single; upper and lower ungual-sheath scales covering base of claws, leaving tips well exposed. Palms and soles with small juxtaposed scales (possibly raised but too desiccated to verify for certain). A weakly enlarged thenar scale, with slightly produced inner edge, on inner margin of palm at base of pollex. Subdigital lamellae mostly single, but a few divided at bases of digits. Longest (4th) finger with 14 subdigital lamellae, longest (4th) toe with 19 subdigital lamellae.

COLORATION: In life (fig. 1), brown above with irregularly distributed squarish black markings occupying single scales. A black stripe from snout to eye; a pale brown blackedged light stripe from eye to shoulder. Underside of head bluish gray with dark speckling; venter and undersides of limbs mottled black and pale bluish gray, with slight tinges of orange on belly and base of tail; black pigmentation increasing onto base of tail, becoming solid black posteriorly. All pattern elements of the holotype well retained in preservative (figs. 2–3), with ground color a duller light brown above, grayish below.

HEMIPENIS: The genitalia of the holotype had been everted during preservation. The attached, fully everted right hemipenis is 8 mm long and 6 mm across its widest point; the appressed organ extends to the suture between the sixth and seventh transverse rows of caudal scales. The left organ was detached by Jadin and inflated with blue-dyed petroleum jelly to provide contrast (fig. 6). The right organ subsequently was inflated in situ and illustrated in apical view without removal from the specimen (fig. 7).

The broad hemipenis, tapered near the base, is weakly and symmetrically bilobed. The sulcus spermaticus curves halfway around the base of the organ before running a medial course, which is flanked by a broad nude area on each side (fig. 6, left). The sulcus extends into the center of the crotch to a raised wedge of tissue, where the sulcus bifurcates inconspicuously and centripetally, with a broad indefinite ‘‘branch’’ on the medial side of each lobe (the branches are ill defined).

The base of the hemipenis is nude (obscured by knotted thread in fig. 6). About 12–13 chevron-shaped pairs of oblique plicae or flounces occupy most of the asulcate side, the members of a pair failing to meet at the midline (fig. 6, right). The several basal pairs of plicae are very short. The plicae bear comblike rows of minute mineralized spinules that project slightly from the edges of the plicae and increase in size towards proximal ends of the plicae; the spinules are largest in the short basal plicae, where the terminal ones attain approximately 0.25–0.3 mm in length.

There are widely separated pairs of oblique plicae on the sulcate face of the hemipenis (fig. 6, left), also with comblike rows of spinules. The proximal and middle sulcateside plicae extend weakly around the sides of the organ to connect with the pronounced plicae on the asulcate sides (fig. 6, center).

The apices of the hemipenial lobes show a complex but symmetrical configuration of folded tissue (fig. 7). A transverse fold from the asulcate face of each lobe gives the appearance of a low hood lying across each head. A circular bare space in front of each ‘‘hood’’ is rimmed below by a collar of thin tissue rising from the upper sulcate side of the organ—possibly a shallow basin for concentrating seminal fluid. A facing pair of flaps extend mediad from the circular bare space, to overlap the lobular cleft. Concealed deep on the medial sides of the lobes, part of each broad ‘‘branch’’ of the sulcus spermaticus disappears distally under a fold of tissue. 5

COMPARISONS

Euspondylus auyanensis is a distinctive lizard that is assignable to the subfamily Cercosaurinae sensu Castoe et al. (2004) ; these authors recognized four additional subfamilies in their classification of Gymnophthalmidae . The presence of rows of hemipenial spinules and posteriorly convex parietal-interparietal margin distinguish E. auyanensis from the Alopoglossinae ; movable eyelids from the Gymnophthalminae ; external ear openings from the Rhachisaurinae ; and rectangular dorsal scales and heterogeneous lateral scales distinguish it from the Ecpleopinae.

Within the Cercosaurinae , Euspondylus auyanensis is not easily placed to genus. In general physiognomy, it bears resemblance to species of Euspondylus and Riama (formerly Proctoporus in part; see Doan and Castoe, 2005). However, Riama (as well as Petracola and some Pholidobolus spp. ) is distinguished by absence of prefrontal scales, evidently a

5 It seemed possible, but could not be demonstrated by probing or minimal dissection, that there might be a route for seminal fluid to flow under the folding and emerge from under the ‘‘hoods’’ onto the bare spaces confined by collars of tissue. In any case, the facing sides of the bare spaces extend narrowly under the facing flaps to the upper medial surfaces of the lobes. From there, the collared bare spaces seem likely to collect and concentrate seminal fluid on the apices of the everted lobes.

constant character in that genus ( Doan and Castoe, 2005: 411). Euspondylus , on the other hand is not readily diagnosed, as pointed out by Uzzell (1973: 4):

The genus Euspondylus , although one of the earliest names in Group II [5 Gymnophthalmidae in part] ( Boulenger, 1885) of the family Teiidae , remains one of the most ill defined, largely because the type species of the genus, Euspondylus maculatus Tschudi (1845) , is essentially devoid of unusual external morphological features on which a generic concept could be founded. As a result Euspondylus became a wastebasket.

The above tradition continues with our assignment of the new species to Euspondylus , a genus badly in need of revision.

The male holotype of Euspondylus auyanensis was compared directly with a larger female specimen of the generic type species, Euspondylus maculatus (AMNH R-1704, 75 mm SVL, from ‘‘Juliaca, Lake Aracona, 16,600 ft.,’’ 6 Peru). There are no essential resemblances in color pattern, but tongue

6 This locality is cited in both old and recent literature on the basis of AMNH catalogue entries. Because of the high elevation (. 5000 m), some authors have speculated that it is an erroneous locality for AMNH amphibians, reptiles, birds, and mammals collected by H.H. Keays. Former AMNH Research Associate and Peruvian authority Harvey Bassler (1883–1950) suggested to E.R. Dunn that material labeled Juliaca had probably been collected at about 3000 ft. [, 900 m] in the vicinity of Inca Mine, near Santo Domingo, Puno. See Dunn (1942: 459); also Uzzell (1970: 26; 1973: 31, 57–58). AMNH ornithologist John Zimmer (1889–1957) was of the same opinion (fide Vaurie, 1972: 19; Stephens and Traylor, 1983: 103).

However, generally forgotten was the fact that Keays himself had cleared up the confusion in a letter to AMNH mammalogist Joel A. Allen (1838–1921): According to Allen (1901: 41) ‘‘Mr. Keays’s post-office address was Juliaca … In a later letter Mr. Keays informs me that the Inca Mines are situated about 200 miles northeast of Juliaca, on the east side of the Andes, on the Inambary River [5 Río Inambari], a tributary of the Amazon, and at much lower altitude than Juliaca. The altitude and geographical position were correctly given in the former paper, but in place of Juliaca … read Inca Mines’’. Keays had earlier given the elevation as 6000 ft. and coordinates 13 ° 30 9 S, 70 ° W, in country ‘‘very broken, with deep narrow canons … covered with a dense undergrowth of shrubs and vines, with here or there a palmetto or a cedar rising above the surrounding vegetation’’ ( Allen, 1900: 219). The locality can be properly cited as ‘‘Inca Mines, Río Inambari, 6000 ft. [1829 m], 13 ° 30 9 S, 70 ° W, Puno, Peru.

morphology, general physiognomy, and scutellation are similar. Both specimens have the lateral body scales much smaller than the dorsals, with most of the transverse rows of dorsal scales laterally splitting into two rows of small scales. There are, however, differences worth noting: The specimen of E. maculatus has, in addition to the collar fold, an anterior gular crease between the ears and a weak gular fold across the throat; the frenocular is clearly present (not fused with loreal); the dorsal scales are striated and lack median keels.

Mijares-Urrutia et al. (2000) reviewed the two Venezuelan species that are still assigned to Euspondylus , namely E. acutirostris and their new E. monsfumus . These are cloudforest lizards of the Cordillera de la Costa, with the eastern monsfumus known only from Cerro El Humo in the Península de Paria. Mijares-Urrutia et al. (2000) gave an LRC (SVL) length of 46.0 mm for the female holotype of E. monsfumus ; SVL lengths for E. acutirostris were given as:

Males: 44.6±2.5 (41.9–49.0 mm), n 5 7

Females: 48.2±3.89 (43.8–53.5 mm), n 5 5

Euspondylus acutirostris and E. monsfumus are noticeably smaller and more slender lizards than the female specimen of E. maculatus (75 mm SVL) or the male holotype of E. auyanensis (59.6 mm SVL, 152 mm total length).

The unique specimen of E. auyanensis was compared with a small series of E. acutirostris from Rancho Grande in northwestern Venezuela (AMNH R-137247, 137254– 137259); the series includes an apparently adult female smaller than the range for females given above (AMNH R-137257, 39 mm SVL, about 115 mm total length). The color pattern of E. acutirostris is rather variable: a middorsal line of dark pigment, a vivid pale dorsolateral line, and lateral ocelli on the dark flanks are characters that are variably present or absent; the usually pale venter sometimes is suffused with dusky pigment, but it lacks bold black markings.

Size, habitus, and color pattern differences notwithstanding, E. auyanensis is conceivably congeneric with Venezuelan E. acutirostris and the similar E. monsfumus . Scutellation is generally similar, although acutirostris has a pair of large postparietals behind the interparietal, lacks the enlarged postgenials of auyanensis , and has a definite frenocular. These Venezuelan species differ from the specimen of E. maculatus in lacking both the anterior gular crease between the ears and the weak gular fold anterior to the gular collar (characters of uncertain significance at the moment). Montero et al. (2002) posited that Euspondylus acutirostris is closely related to Anadia sensu lato, showing E. acutirostris in a clade bordered by Anadia spp. 7

Euspondylus auyanensis has been referred to as ‘‘ Anadia sp. ,’’ but the lateral zone of small body scales immediately differentiates Euspondylus auyanensis from species of Anadia , which lack ‘‘a distinct band of much smaller scales along each side’’ ( Oftedal, 1974: 206). Lateral scales in Anadia may be smaller than the dorsals, but the transverse rows continue unbroken (except near limb insertions) onto the sides of the body. With rare exception ( A. escalerae described herein), species of Anadia differ from Euspondylus in having smooth rather than keeled dorsal scales. Species belonging to Anadia sensu stricto (at least including Oftedal’s [1974] ocellata group) are elegantly slender and attenuate lizards (fig. 11); these are much different in habitus from any Euspondylus except for possibly the rare E. simonsii . 8 The keeled dorsals as well as the zone of small lateral body scales immediately differentiates E. auyanensis from the heavier bodied species currently assigned to Anadia (e.g., A. blakei , figs. 12–13).

7 However, of the few specimens of E. acutirostris used by Montero et al. (2002), one exchange specimen originally had been part of a series of four specimens at the Museo de Historia Natural La Salle (MHNLS). During his time on the staff there, Rivas re-identified the remaining three specimens as young Anadia marmorata , leaving one to wonder if the fourth specimen (formerly MHNLS 12678) had been also misidentified as E. acutirostris .

8 D.M. Harris (personal commun.) informed us that the British Museum holotype of the Peruvian Euspondylus simonsii Boulenger ‘‘is at least as slender as Anadia petersi or A. rhombifera ,’’ which seems confirmed by a specimen of simonsii (AMNH R-104284) from 1560 m in Depto. Huánuco, Peru.

REMARKS

Euspondylus auyanensis is known to have been collected on only two of the many expeditions to Auyantepui. The 1994 AMNH– TERRAMAR Expedition failed to find it during a month’s fieldwork in February and Stefan Gorzula found it only on one of his several trips to Auyantepui. Gorzula collected several specimens, all of which seem to have been lost. Myers and Donnelly (2008: 88–89) summarized the history:

Gorzula (1992: 276) discovered an unnamed species of Anadia on Auyantepui in 1984. According to Gorzula and Señaris (1999: 115–117) the species is known only from a single collection of seven specimens obtained ‘‘ 6 miles E Angel Falls’’ in May and June. The specimens were found mostly in concealment by day, in association with the frogs Stefania schuberti and Tepuihyla edelcae and the lizard Tropidurus bogerti . One ‘‘was observed basking on the edge of a vegetation mat … [and on] being approached it dove into a small pool that was about 6 cm deep, and hid in the detritus on the bottom.’’

Gorzula and Señaris were unable to ascertain the present whereabouts of the specimens and therefore refrained from formally describing the species. They did, however, describe the individual lizard that was to have been designated holotype and indicated variation in the potential paratypes. The color in life ‘‘was dark olive with irregularly distributed black flecks … ventral color of females was white with irregular black spots … [male ventral color] similar to that of the females except … tinged with red.’’ Illustrations were unavailable.

Gorzula and Señaris (1999: 115–117) provided a detailed description of one lost specimen and notes on the others; measurements, however, had not been taken. The specimen described in detail had ‘‘loreal (frenocular?) large, contacting prefrontal and supralabials’’; this was not indicated as a variable character and presumably applied to all specimens. The same condition, which we interpret as fusion of loreal + frenocular, also pertains to the holotype (fig. 2, upper right) and may be characteristic of the species. However, the scale anterior to the elongate subocular (fig. 2, upper right) might be interpreted as a reduced, posteriorly positioned frenocular. In any case, presence or absence of a frenocular is a variable character in some gymnophthalmids, as in Anadia blakei (q.v.).

Gorzula’s locality lies in the northern part of the Auyán summit, whereas the type locality is at the southern edge. It would seem to be a fairly conspicuous lizard when it ventures out from cover, but hard to find if it seeks dry-season sanctuary in deep rock crevices. Euspondylus auyanensis is assumed to be endemic to the summit area.