Wetmorena obscura, Schools & Hedges, 2024

Schools, Molly & Hedges, Blair, 2024, A new forest lizard fauna from Caribbean islands (Squamata, Diploglossidae, Celestinae), Zootaxa 5554 (1), pp. 1-306 : 267-270

Wetmorena obscura sp. nov.

Long-fingered Earless Forest Lizard

(Fig. 102)

Wetmorena haetiana surda — Schwartz, 1965:41 (part).

Wetmorena haetiana surda — Schwartz & Henderson, 1991:553 (part).

Celestus haetianus surdus — Hedges et al., 2019:17 (part).

Holotype. USNM 328904, a juvenile from Gros Cheval (ca. 15 km W of, via logging roads, NE slope of Pic La Selle), collected by S. Blair Hedges and Richard Thomas on 18 November 1984 (18.3367, -71.8686; 2,020 m).

Paratypes (n=2). HAITI. Sud-Est. USNM 328905–6 , same locality, date, and collectors as holotype .

Diagnosis. Wetmorena obscura sp. nov. has (1) a dorsal pattern of lineate, (2) head markings present, (3) markings in the longitudinal paramedian area present, (4) dots arranged in bars in the lateral band absent, (5) a maximum SVL of 46.9–61.1 mm, (6) ventral scale rows, 108–111, (7) midbody scale rows, 35–36, (8) total lamellae on one hand, 20–21, (9) total strigae on ten scales, 73–83, (10) relative length of all digits on one hindlimb, 13.8–16.2 %, (11) relative distance between the angled subocular and mouth, 0.295 –0.426 %, (12) relative eye length, 2.65–3.13 %, (13) relative forelimb length, 13.6–16.3 %, (14) relative ear width, 0.00 %, (15) relative rostral height, 1.72–2.22 %, (16) relative head length, not applicable, (17) relative mental width, 1.72–2.24 %, (18) relative postmental width, 2.49–3.05 %, (19) relative cloacal width, 6.26–6.69 %, (20) relative prefrontal width, 4.03–4.58 %, (21) relative largest supraocular width, 1.70–2.54 %, (22) relative longest finger length, 4.08–5.35 %, (23) relative distance between the ear and eye, not applicable, (24) relative head width, not applicable, (25) relative frontal width, 73.6–81.9 %, (26) relative nasal height, 0.753–1.24 %, (27) relative angled subocular height, 0.999– 1.29 %, (28) relative distance between the eye and naris, 3.68–5.01 %, (29) relative canthal iii length, 0.835 –0.980 %, (30) relative angled subocular width, 1.82–2.17 %, and (31) relative nasal length, 1.41–1.57 %. The species stem time is 4.75 Ma and the species crown time is 0.00 Ma (Fig. 4).

Wetmorena obscura sp. nov. has a lower number of total strigae on ten scales (73–83) than all other species of the genus. From Wetmorena agasepsoides , we distinguish W. obscura sp. nov. by the dorsal pattern (lineate versus absent), the midbody scale rows (35–36 versus 27–31), the total lamellae on one hand (20–21 versus 14–17), the total strigae on ten scales (73–83 versus 94–153), the relative length of digits on one hindlimb (13.8–16.2 versus 9.44–11.2), the relative distance between angled subocular and mouth (0.295 –0.426 versus 0.00–0.224), the relative forelimb length (13.6–16.3 versus 8.05–9.58), the relative ear width (0.00 versus 0.292 –0.634), the relative mental width (1.72–2.24 versus 1.40–1.66), the relative postmental width (2.49–3.05 versus 1.75–2.30), the relative prefrontal width (4.03–4.58 versus 2.77–3.35), the relative longest finger length (4.08–5.35 versus 1.44–2.01), and the relative distance between the eye and naris (3.68–5.01 versus 2.25–3.27). From W. haetiana , we distinguish W. obscura sp. nov. by the adult SVL (46.9–61.1 versus 78.3–102), the total strigae on ten scales (73–83 versus 96–144), and the relative longest finger length (4.08–5.35 versus 2.65–3.63). From W. mylica , we distinguish W. obscura sp. nov. by the dorsal pattern (lineate versus absent/irregular dots), the adult SVL (46.9–61.1 versus 76.0– 98.2), the ventral scale rows (108–111 versus 112–126), the midbody scale rows (35–36 versus 37–41), the total strigae on ten scales (73–83 versus 84–105), the relative prefrontal width (4.03–4.58 versus 3.26–4.01), the relative longest finger length (4.08–5.35 versus 2.43–2.95), the relative frontal width (73.6–81.9 versus 84.8–114), and the relative distance between the eye and naris (3.68–5.01 versus 3.10–3.67). From W. orosaura sp. nov., we distinguish W. obscura sp. nov. by the total lamellae on one hand (20–21 versus 22–26), the total strigae on ten scales (73–83 versus 92–98), the relative length of digits on one hindlimb (13.8–16.2 versus 18.6–19.7), the relative distance between angled subocular and mouth (0.295 –0.426 versus 0.206 –0.285), the relative forelimb length (13.6–16.3 versus 16.9–17.2), the relative width of canthal iii (0.835 –0.980 versus 1.14–1.26), and the relative angled subocular width (1.82–2.17 versus 2.21–2.47). From W. surda , we distinguish W. obscura sp. nov. by the adult SVL (46.9–61.1 versus 62.5–81.9), the total strigae on ten scales (73–83 versus 84–123), the relative prefrontal width (4.03–4.58 versus 3.47–3.91), the relative longest finger length (4.08–5.35 versus 2.12–2.98), and the relative width of canthal iii (0.835 –0.980 versus 1.17–1.33).

Description of holotype. USNM 328904. An adult; SVL 61.1 mm; tail nearly cylindrical, broken, 25.4 mm (41.6% SVL); axilla-to-groin distance 37.3 mm (61.0% SVL); forelimb length 8.29 mm (13.6% SVL); hindlimb length 12.3 mm (20.1% SVL); head width 7.34 mm (12.0% SVL); diameter of orbit 1.62 mm (2.65% SVL); horizontal diameter of ear opening 0.00 mm (0.00% SVL); vertical diameter of ear opening 0.00 mm (0.00% SVL); length of all toes on one foot 8.80 mm (14.4% SVL); shortest distance between angled subocular and lip 0.18 mm (0.295% SVL); longest finger length 2.49 mm (4.08% SVL); largest supraocular width 1.04 mm (1.70% SVL); cloacal width 4.09 mm (6.69% SVL); mental width 1.20 mm (1.96% SVL); prefrontal width 2.52 mm (4.12% SVL); frontal width 81.9% frontal length; nasal height 0.46 mm (0.753% SVL); angled subocular height 0.79 mm (1.29% SVL); shortest distance between the eye and naris 3.06 mm (5.01% SVL); canthal iii width 0.51 mm (0.835% SVL); angled subocular width 1.11 mm (1.82% SVL); nasal width 0.96 mm (1.57% SVL); rostral 1.72X as wide as high, barely visible from above, not in contact with nasals, in contact with 1 st supralabial and anterior internasal (left)/(right); anterior internasals are narrower than posterior ones; frontonasals and prefrontal fused into a single large plate with a straight posterior margin, wider than long, bordered by posterior internasals, 1 st loreals, 1 st median oculars, and the frontal; frontal longer than wide; a pair of frontoparietals (missing on the right), separated by the posterior prolongation of the frontal and the interparietal plate; interparietal plate smaller than parietals and separating them, posteriorly touching the interoccipital, which is wider than long; parietal separated from supraoculars by 1 st and 2 nd temporals and frontoparietal (left)/(right); nasal single; nostril just posterior to suture between 1 st and 2 nd supralabials (left)/(right); 1 postnasal (left)/(right); 2 loreals (left)/(right); 1 st loreal higher than wide (left)/(right), in contact with postnasal, posterior internasal, prefrontal/frontonasal complex, 1 st median ocular, canthal iii, 2 nd loreal, and 3 rd supralabials (left)/(right); 2 nd loreal shorter than 1 st, higher than wide (left)/(right), excluded from contact with supraocular by canthal iii (left)/(right); 2 nd loreal posteriorly bordering the lower preocular (left)/(right); canthal iii wider than high (left)/(right), contacting 1 st median ocular, anterior supraciliary, upper preocular, and 1 st and 2 nd loreals (left)/(right); 9 median oculars (left)/(right), 1 st contacting the prefrontal (left)/(right); 1 upper preocular (left)/(right); an irregular anterior supraciliary (left)/(right); 6 lateral oculars (left)/(right); 5 temporals (left)/(right); 2 suboculars (left)/(right); posterior subocular large and elongate (left)/(right); anterior subocular small (left)/(right); 9 supralabials (left)/(right), 5 to level below center of eye (left)/(right); 9 infralabials (left)/(right), 6 to level below center of eye (left)/(right); mental small, followed by 2 post mentals, the first small and the second large; 4 pairs of enlarged chin shields; 1 st pair in contact with one another; 2 nd –4 th pairs separated by 1–3 scales; 112 transverse rows of dorsal scales from interoccipital to base of tail; 108 transverse rows of ventral scales from mental to vent; 35 scales around midbody; 4 digits; finger lengths 3>2>4>1; 6 lamellae under longest finger (left)/(right); 20 total lamellae on one hand; toe lengths 3>2>4>1; 11 lamellae under longest toe (left)/(right); keelless and striate dorsal body and caudal scales; smooth ventral scales; 83 total strigae counted on ten scales.

Color (in alcohol): dorsal surface of head gray-brown with darker brown areas on scale borders and in irregular spots; lateral surfaces of head grading from gray-brown to faded gray-brown with darker brown eye masks and areas on the labial scales; dorsal surfaces of the body are gray-brown with darker brown spots arranged in broken longitudinal paramedian lines that continue as multiple lines down the back; dorsal surface of tail the same as the body; lateral areas grade from dark brown to gray with paler spots; dorsal surfaces of the limbs are dark brown with paler mottling; lateral and ventral areas of the limbs grade to pale brown with darker mottling; ventral surfaces of the head, body, and tail are pale gray-brown covered in dark brown mottling that becomes heavier posteriorly.

FIGURE 102. (A–F) Wetmorena obscura sp. nov. (USNM 328904, holotype), SVL 61.1 mm.

Variation. The two USNM paratypes ( USNM 328905–6 ) resemble the holotype in pattern and scalation. All specimens have head markings in the form of a darker outline on head scale borders. USNM 328904 also has dark, irregular areas on its head scales. The dots arranged in bars in the lateral band are either absent or appear as mottling. Measurements and other morphological data for the holotype and other examined material are presented in Table 1 .

Distribution. Wetmorena obscura sp. nov. is known only from the locality of the type series, which was collected in southeastern Haiti at an elevation of 2020 m (Fig. 95). It has an extent of occurrence of ~ 90 km 2.

Ecology and conservation. The type series was collected under rocks in pine forest (SBH, field data). We consider the conservation status of Wetmorena obscura sp. nov. to be Critically Endangered B1ab(iii), based on IUCN Redlist criteria ( IUCN 2023). It faces a primary threat from habitat destruction resulting from agriculture and charcoaling. Haiti is heavily deforested with <1% of nation’s primary forest remaining ( Hedges et al. 2018). Secondary threats to this species include predation from introduced predators, including the mongoose and black rats. Studies are needed to determine the health of any remaining populations and threats to the survival of the species.

Reproduction. No data on reproduction are available for this species.

Etymology. The species name ( obscura ) is a Latin feminine singular adjective meaning “dark” in reference to the dark color of this species.

Remarks. Previously regarded as Wetmorena haetiana surda , we recognize W. obscura sp. nov. as a full species based on its genetic and morphological distinctiveness. Additional specimens in museum collections catalogued as W. haetiana or W. haetiana surda should be examined to determine if they are additional specimens of this species.

Wetmorena obscura sp. nov. is included in our genetic dataset and has significant support in both Bayesian and ML likelihood analyses at the crown node. The stem node that places W. obscura sp. nov. as the closest relative of W. agasepsoides has a support value of 66% in our ML analysis and is not supported in our Bayesian analysis. Using genomic data, Schools et al. (2022) placed W. agasepsoides as the outgroup to all other species of Wetmorena with significant support in both ML and Bayesian analyses. Based on our timetree (Fig. 4), W. obscura sp. nov. diverged from its closest relative ( W. agasepsoides ) 4.75 Ma, consistent with typical species of vertebrates (> 0.7 Ma; Hedges et al. 2015). Although not scored in our suite of diagnostic characters, W. obscura has the darkest dorsal color of the genus Wetmorena . Wetmorena obscura sp. nov. was recovered as conspecific with Wetmorena surda in our ASAP analysis.