Lepidophyma jasonjonesi, Grünwald & Reyes-Velasco & Ahumada-Carrillo & Montaño-Ruvalcaba & Franz-Chávez & La Forest & Ramírez-Chaparro & Terán-Juárez & Borja-Jiménez, 2023

Gruenwald, Christoph I., Reyes-Velasco, Jacobo, Ahumada-Carrillo, Ivan T., Montano-Ruvalcaba, Carlos, Franz-Chavez, Hector, La Forest, Brandon T., Ramirez-Chaparro, Ricardo, Teran-Juarez, Sergio & Borja-Jimenez, Juan Miguel, 2023, A new species of saxicolous Lepidophyma (Squamata, Xantusiidae) from Tamaulipas, Mexico, Herpetozoa 36, pp. 9-21 : 9

publication ID	https://dx.doi.org/10.3897/herpetozoa.36.e96184
publication LSID	lsid:zoobank.org:pub:ED535B9B-15AC-4F12-8DD6-A11A21DACE42
persistent identifier	https://treatment.plazi.org/id/7389A805-0166-4D07-9D18-02372E324B4E
taxon LSID	lsid:zoobank.org:act:7389A805-0166-4D07-9D18-02372E324B4E
treatment provided by	Herpetozoa by Pensoft
scientific name	Lepidophyma jasonjonesi
status	sp. nov.

Treatment

Lepidophyma jasonjonesi sp. nov.

Figs 2 View Figure 2 , 3 View Figure 3

Type material.

Holotype (Fig. 2 View Figure 2 ). INIRENA 2817 (Original field number CIG-0969). Adult male collected in a rock crevice near a small seep, 28 km NNE of Jaumave, on Federal Highway 101 to Ciudad Victoria, Municipio de Victoria, Tamaulipas, Mexico (23.617489, -99.285573, 1,005 m a.s.l.; datum = WGS84) (Fig. 3 View Figure 3 ), by Jason M. Jones and Ivan Ahumada-Carrillo on 26 July 2016.

Paratypes (Fig. 4 View Figure 4 ). INIRENA 2818 (Original field number CIG-0970). Adult male, with the same collection data as the Holotype.

Diagnosis.

Lepidophyma jasonjonesi sp. nov. can be distinguished from all its congeners by the following combination of characters: flattened head and body, head height 31-32% of head length; anterior pretympanic plate large, similar size as anterior supratemporal; 52-54 gular scales; 0-1 gular scales contacting first pair of infralabials; 180-182 dorsal scales mid-ventrally between occipitals and rump; 17-18 enlarged tubercles in paravertebral row between axilla and groin, 16 enlarged tubercles in second vertebral row between axilla and groin; 37-40 total femoral pores; 27-30 lamellae on fourth toe of foot, with 10-15 divided mid-ventrally; 35-38 ventral scale rows, with 10 longitudinal ventral scale rows; iris brown.

Comparisons.

One of the most striking characteristics of this species which distinguish it amongst known Lepidophyma is the flattened head and body shape. While this character is not very evident from photos, it is evident when a specimen is in hand. We have included detailed photos of the head, including from a lateral profile (Fig. 5 View Figure 5 ; Suppl. material 1: plate S1), which best portrays this unique flattening of the head. This species can be distinguished from most Lepidophyma , except L. chicoasense , L. lipetzi , L. flavimaculatum , L. ramirezi and L. zongolica by the high number (37-40) of total femoral pores, vs. 14-36 in the other species. It further differs from most species of Lepidophyma , except L. smithii and L. tarascae , by possessing 16 lateral tubercle rows between the axilla and the groin, vs. 21-73 in the other species. It can be distinguished from members of the L. gaigeae group as defined by Bezy and Camarillo (1992, 2002), Canseco-Márquez et al. (2008) and Arenas-Moreno et al. (2021) by possessing enlarged tubercles interspersed amongst the small granular scales, including on the anterior and lateral portions of the body, vs. no enlarged tubercles in L. cuicateca , L. dontomasi , L. gaigeae , L. lowei , L. lusca and L. radula . L. jasonjonesi sp. nov. is most closely related to L. sylvaticum and L. micropholis (see results below). L. jasonjonesi sp. nov. differs from L. micropholis in the following manner ( L. micropholis character states in parenthesis): a more flattened head and body build (vs. not flattened), HH/HL ratio of 0.31-0.32% (vs. 0.35-0.37), larger dorsal scales in 180-182 dorsal scale rows (vs. smaller dorsal scales in 231-251 dorsal scale rows), 37-40 femoral pores (vs. 28-36), 16 lateral rows of tubercles (vs. 27-35), 52-54 gulars (vs. 55-68).

L. jasonjonesi sp. nov. differs from L. sylvaticum in the following manner ( L. sylvaticum character states in parenthesis): a more flattened head and body build (vs. not flattened), HH/HL ratio of 0.31-0.32 (vs. 0.41-0.45), tympanum with upper part tilted approximately 20° posteriorly, allowing for a more flattened head-shape (vs. tympanum not tilted posteriorly), lacking enlarged tubercles on the lateral portions of the body, giving a smooth appearance (vs. enlarged lateral tubercles present, rugose appearance), 37-40 femoral pores (vs. 24-36). L. jasonjonesi sp. nov. can be distinguished from arid-land populations assigned to L. sylvaticum by Bezy (1984) by possessing more 180-182 mid-dorsal scales (vs. 150-178), by possessing one pretympanic scale separating postocular from second postorbital supralabial (vs. 2-3), by possessing 52-54 gulars (vs. 42-49) and by possessing 17-18 enlarged tubercles in the paravertebral row (vs. 15-17). We include mensural ranges for the six key characters of all currently-recognised species of Lepidophyma for comparative purposes in Table 1 View Table 1 .

Description of the holotype

(Fig. 2 View Figure 2 ). An adult male, with a rostral broader than high (2.2 mm broad, 1.15 mm high), followed by nasals which are in contact with median frontonasal; two prefrontals; two frontoparietals; no frontal; interparietal scale without parietal spot, but with parietal organ slightly visible and two parietals on the sides. Interparietal scale in contact with supraoculars, parietals and occipitals. Naris bordered by frontonasal, postnasal and first supralabial. Followed by two loreal scales, anterior loreal scale taller than postnasal and posterior loreal scale largest. Eight supralabials on both sides, fifth touching eye, sixth sub-square on left (1.3 tall long, 1.1 mm tall) and rectangular on right (1.6 mm long, 1.1 mm tall) and largest supralabial on both sides is seventh, rectangular in shape and on left 1.6 mm long, 1.1 mm tall and on right 1.8 mm long, 1.1 mm tall. Lower elongated postocular in contact with sixth supralabial on both sides.

Three supratemporal scales, first supratemporal scale in contact with parietal, second supratemporal scale is largest and in contact with parietal and occipital and third supratemporal in contact with occipital. The second supratemporal scale (3.8 mm long, 2.7 mm tall) is larger than the parietal (3.0 mm long, 2.8 mm wide). One large pretympanic scale between postoculars and seventh supralabial on both sides, with a reduced number of scales in temporal region, on left side, one large pretympanic scale and two small scales between anterior temporal and sixth and seventh supralabial, on right side only one large pretympanic scale between anterior temporal and sixth and seventh supralabials. The enlarged pretympanic scale (1.1 mm long, 1.0 mm tall) is subequal to the anterior temporal scale (1.2 mm long, 1.1 mm tall). Seven enlarged auricular scales bordering anterior portion of auricular opening, upper one dark and lower seven pale. Mental broader than long (2.7 mm broad, 2.3 mm long), follow by five pairs infralabials on both sides, the second and third are largest and the fifth is very reduced. Orbit in contact with one elongate preocular, fifth supralabial, two elongated postoculars and supraocular. No gulars contacting first pair of infralabials; 52 gulars along the ventral mid-line between second pair of infralabials and posterior gular fold.

The dorsal and lateral surfaces of the body covered by small granular scales of varying sizes, interspaced with enlarged tubercles, some of which are weakly keeled and some smooth (approximately three times the size of adjacent dorsal scales). Eighteen enlarged paravertebral tubercles from above axilla to above groin in the paravertebral row. One hundred and eighty dorsal scales along the vertebral line from the posterior edge of the occipitals to above the vent.

Square ventral scales are smooth and flat, in 10 longitudinal rows at mid-body; the lateral rows slightly smaller and keeled. Thirty-five transverse rows of ventral scales between gular fold and vent, including the anterior and posterior pre-anal scales. Scales on ventral surface of limbs heterogeneous in size, 37 total femoral pores (20 / 17). Twenty-nine sub-digital lamellae on fourth toe of left foot, 27 on fourth toe of right foot.

Regenerated tail approximately 80 mm long, regenerated at 25 mm from base. The unregenerated part with complete enlarged whorls, each separated by three rows of interwhorls; on ventral portion of tail these rows reduce to two.

Colouration in life

(Figs 2 View Figure 2 , 3 View Figure 3 ). Dorsal colouration of head chocolate brown; with a greenish tinge on the frontonasals, prefrontals and frontoparietals; interparietal, occipitals and supratemporals chocolate brown. Upper labials yellow, with a dark brown irregular loreal stripe which runs from the tip of the snout to the lower posterior edge of the occipitals. Dark loreal stripe chocolate brown and extends down on to third supralabial. Dorsal ground colouration of dorsum yellowish-cream, with unmarked pale yellowish-cream stripe down mid-dorsal region. Black reticulation on lateral portions of dorsum and flanks, with pale yellow highlights forming indistinct occelli. Tail pale grey with black blotches. Ventral colouration of head yellowish-cream, with brown spots. Venter white, with grey spots on throat and tail. Iris brass-copper coloured.

Colouration in preservative.

After several years in preservative, the dorsal colouration of the head light tan, with green tinge faded away. Dark melanophores spread evenly on all large head scales. Labial region yellowish-cream ground colouration with one dark brown blotch on each supralabial, centred on the anterior five supralabials, concentrated on the posterior portion of the sixth supralabials and covering the most of the seventh and eight supralabials. Dark brown loreal lateral stripe on head begins anterior to naris, proceeds posteriorly through loreal region, where it extends down on to third supralabial and then posterior through upper orbit and posteriorly through the supratemporal scales to above the tympanum. The dorsal colouration of the body is pale tan, with two broken rows of dark brown blotches dorso-laterally and then dark brown spotting and reticulation. The mid-dorsal area, between the two paravertebral tubercle rows, is pale tan and complete unmarked. Two rows of pale cream ocelli are present between the rows of dark brown blotches, with 10-11 pale ocelli present per row. Dorsal colouration of tail pale cream with remnants of dark brown blotches turning into two alternating rows of dark brown spots. Tail is regenerated after proximal third and the regenerated portion lacks dark brown spots. Ventral colouration yellowish-cream. Ventral surface of head and throat yellowish-cream, with dark spotting. Three dark brown blotches on postmental, which are composed of dense clusters of little dark brown spots. These dark brown blotches continue on to the infralabials, where they are arranged in subequal pairs, the larger one nearest to the mouth. The throat has approximately 50 brown spots which consist of one gular each and extend back to the thirtieth row of gulars. The latter portion of the throat unmarked, cream. Venter unmarked, cream, lateral two rows of ventral scales haves some dark black stippling along the scale edges, most concentrated towards the anterior portion of the scale. Ventral portions of arms, hands, thighs, legs and feet are cream, unmarked. Ventral surface of tail white, unmarked. Eye black.

Measurements

(mm). SVL 61.0 mm; TL 79.8 mm; TotL; 140.8 HL 15.1 mm; HW 9.65 mm; HH 4.7 mm; ED 2.4 mm; 4TL 7.7 mm.

Variation.

Meristic variation of the two available specimens is given in Table 2 View Table 2 . The paratype (INIRENA 2818) possesses a pale spot on the interparietal scale, towards the posterior portion of the scale and roughly encompassing the parietal organ. The paratype has 17 enlarged paravertebral tubercles in the paravertebral row between the axilla and the groin, as well as a total of 40 femoral pores. We have depicted variation of colour pattern of other individuals which were photographed (but not collected) at the type locality (Fig. 6 View Figure 6 ). The dorsal colouration and pattern of all the individuals observed is the same; however, each individual varies slightly by amount and shape of the dark dorsal blotches and pale yellow dorsal ocelli.

Distribution and habitat.

This species is known from semi-arid tropical deciduous forest on the lower leeward slopes of the Sierra Madre Oriental between Ciudad Victoria and Jaumave, Tamaulipas. The vegetation of the tropical deciduous forest in the Jaumave Valley grows to a low height and was described as "thorn desert" (= thornscrub) by Martin (1958). Martin reported 568 mm of mean annual precipitation and a mean annual temperature of 21.2 °C for Jaumave. The Koppen classification for the valley is BSh (hot semi-arid climate). The Jaumave Valley is unique for its Cactacea biodiversity and endemism ( Martin 1958). Lepidophyma jasonjonesi sp. nov. is known with certainty only from 1005 m elev. at the type locality (Fig. 3 View Figure 3 ), where it has been observed on several occasions. Sight records of small saxicolous Lepidophyma at other points along this stretch of highway and near it are likely to be of this species and we have included one of these on the distribution map (Fig. 7 View Figure 7 ). A specimen from Gomez Farías, Tamaulipas (CIG 2050) appears to represent this species; however, we have decided not to include it as a paratype pending further molecular work. A population of Lepidophyma from San Roque (Nuevo León) is closely related, but whether it represent this species remains unresolved (see below, Fig. 8 View Figure 8 ).

Etymology.

Named in honour of Jason Michael Jones, American-Mexican herpetologist and savvy field collector, who has always shared a profound interest for members of the family Xantusiidae and who collected the type series of the new species.