Comptus alloeides ( Schwartz 1964 )

Schools, Molly & Hedges, Blair, 2024, A new forest lizard fauna from Caribbean islands (Squamata, Diploglossidae, Celestinae), Zootaxa 5554 (1), pp. 1-306 : 107-110

Comptus alloeides ( Schwartz 1964)

Samana Keeled Forest Lizard

(Fig. 36)

Diploglossus stenurus alloeides Schwartz, 1964:18 . Holotype: MCZ R-77152, collected by Richard Thomas 6 km E. Sanchez, Samana, Dominican Republic, on 10 October 1963 (19.227, -69.558; 40 m).

Celestus stenurus alloeides — Schwartz & Henderson, 1988:100.

Celestus stenurus alloeides — Schwartz & Henderson, 1991:378.

Celestus stenurus alloeides — Hedges et al., 2019.

Celestus stenurus alloeides — Schools & Hedges, 2021:226.

Material examined (n=44). DOMINICAN REPUBLIC. Samaná. AMNH 27748 , John King, nr Samaná , 1924 ; AMNH 38376–7 , William G. Hassler, Samaná , 1929 ; AMNH 39877–80 , William G. Hassler, Samaná , November– December 1929 ; AMNH 40232 , William G. Hassler, Laguna, November 1929 ; AMNH 40261–2 , 40264 , 40267–8 , William G. Hassler, Samaná , October–December 1929 ; AMNH 40396 , 40402 , 40404 , William G. Hassler, Samaná , October 1929 ; AMNH 40980 , 40982–3 , John King, Samaná , May 1923 ; KU 226555 , 13 km W Samaná , 30 October 1963 ; KU 226556 , 6 km W Samaná , 1 November 1963 ; KU 226557–60 , 8 km W Samaná , 2 November 1963 ; KU 226561 , 13 km W Samaná , 2 November 1963 ; KU 226562 , 6 km E Sanchez , 30 October 1963 ; KU 226563 , 11 km E Sanchez , 30 October 1963 ; KU 226564–9 , 14 km E Sanchez , 2 November 1963 ; MCZ R-44398, Philip J. Darlington, Jr., Sanchez , 1–31 July 1938 ; MCZ R-77152, Richard Thomas, 6 km E. Sanchez, 10 October 1963 ; USNM 61931 , near Laguna, 10 March 1919 ; USMN 61932 , near Laguna, 7 March 1919 ; USNM 62363–4 , Sanchez , 12 August 1919 ; USNM 66760–1 ; USNM 66975–6 , Laguna, 6 mi NE of Samaná, Samaná Peninsula , February 1924 . Diagnosis. Comptus alloeides has (1) a dorsal pattern of irregular dots/dots in series/dots in chevrons, (2) head markings absent/present, (3) markings in the longitudinal paramedian area present, (4) dots arranged in bars in the lateral band absent/present, (5) an adult SVL of 124–161 mm, (6) ventral scale rows, 84–109, (7) midbody scale rows, 36–44, (8) total lamellae on one hand, 43–58, (9) total strigae on ten scales, 237–323, (10) relative length of all digits on one hindlimb, 23.8–35.2 mm, (11) relative distance between the angled subocular and mouth, 0.587– 1.03 mm, (12) relative eye length, 3.16–3.90 mm, (13) relative forelimb length, 21.4–25.3 mm, (14) relative ear width, 0.710–1.83 mm, (15) relative rostral height, 1.52–1.99 mm, (16) relative head length, 15.5–20.0 mm, (17) relative mental width, 0.840–1.95 mm, (18) relative postmental width, 2.54–2.97 mm, (19) relative cloacal width, 8.86–10.3 mm, (20) relative prefrontal width, 4.25–5.07 mm, (21) relative largest supraocular width, 2.66–2.95 mm, (22) relative longest finger length, 5.32–5.95 mm, (23) relative distance between the ear and eye, 6.43–8.53 mm, (24) relative head width, 70.0– 74.2 mm, (25) relative frontal width, 64.9–75.1 mm, (26) relative nasal height, 0.863–1.30 mm, (27) relative angled subocular height, 0.733–1.23 mm, (28) relative distance between the eye and naris, 4.82–6.77 mm, (29) relative canthal iii length, 1.60–2.20 mm, (30) relative angled subocular width, 2.26–3.01 mm, and (31) relative nasal length, 1.46–2.03 mm. The species stem time is 1.46 Ma and no genetic data are available to estimate the species crown time (Fig. 4) .

We distinguish Comptus alloeides from the other species of Comptus based on a complex of traits. From Comptus arboreus sp. nov., we distinguish C. alloeides by the adult SVL (124–161 versus 93.2–123), the total strigae on ten scales (237–323 versus 143–207), the relative length of digits on one hindlimb (23.8–35.2 versus 37.4–39.7), and the relative longest finger length (5.32–5.95 versus 6.01–6.37). From C. badius , we distinguish C. alloeides by the adult SVL (124–161 versus 78.2–99.1), the relative postmental width (2.54–2.97 versus 2.39), the relative longest finger length (5.32–5.95 versus 4.38–5.04), and the relative head width (70.0–74.2 versus 62.8–69.3). From C. maculatus , we distinguish C. alloeides by the dorsal pattern (irregular dots/dots in series/dots in chevrons versus absent/chevrons), the adult SVL (124–161 versus 60.1–81.3), the total lamellae on one hand (43–58 versus 32–37), the total strigae on ten scales (237–323 versus 149–201), and the relative longest finger length (5.32–5.95 versus 4.14–5.01). From C. stenurus , we distinguish C. alloeides by the total strigae on ten scales (237–323 versus 176– 234). From C. weinlandi , we distinguish C. alloeides by the total strigae on ten scales (237–323 versus 167–236).

Description of holotype. MCZ R-77152. An adult male; SVL 115 mm; tail nearly cylindrical, broken in life midway, regenerated, 113 mm (98.3% SVL); axilla-to-groin distance 63.6 mm (55.3% SVL); forelimb length 25.7 mm (22.3% SVL); hindlimb length 38.2 mm (33.2% SVL); head length 18.9 mm (16.4% SVL); head width 13.8 mm (12.0% SVL); head width 73.0% head length; diameter of orbit 4.34 mm (3.77% SVL); horizontal diameter of ear opening 1.58 mm (1.37% SVL); vertical diameter of ear opening 1.39 mm (1.21% SVL); length of all toes on one foot 34.0 mm (29.6% SVL); shortest distance between angled subocular and lip 0.96 mm (0.835% SVL); shortest distance between the ocular and auricular openings 7.82 mm (6.80% SVL); longest finger length 7.48 mm (6.50% SVL); largest supraocular width 2.89 mm (2.51% SVL); cloacal width 11.4 mm (9.91% SVL); mental width 2.17 mm (1.89% SVL); postmental width 3.21 mm (2.79% SVL); prefrontal width 5.00 mm (4.35% SVL); frontal width 74.9% frontal length; nasal height 1.51 mm (1.31% SVL); angled subocular height 1.07 mm (0.930% SVL); shortest distance between the eye and naris 5.05 mm (4.39% SVL); canthal iii width 2.02 mm (1.76% SVL); angled subocular width 2.00 mm (1.74% SVL); nasal width 2.06 mm (1.79% SVL); rostral 1.53X as wide as high, 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 slightly concave posterior margin, wider than long, bordered by posterior internasals, 1 st loreals, canthal iii (left), 1 st and 2 nd median oculars, and the frontal; frontal longer than wide; a pair of frontoparietals, separated by the posterior prolongation of the frontal and the interparietal plate; interparietal plate much smaller than parietals and separating them, posteriorly touching the interoccipital, which is approximately as wide as long; parietal separated from supraoculars by 1 st and 2 nd temporals and frontoparietal (left)/1 st and 2 nd temporals and frontoparietal (1 st fused with FP) (right); nasal single; nostril above 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, canthal iii, 2 nd loreal, and 3 rd –4 th supralabials (left)/postnasal, posterior internasal, prefrontal/frontonasal complex, median ocular 1, canthal iii, 2 nd loreal, and 3 rd –4 th supralabials(right); 2 nd loreal shorter than 1 st, approximately as high as wide (left)/(right), excluded from contact with supraocular by canthal iii (left)/(right); final loreal posteriorly bordering the upper and lower preoculars (left)/(right); canthal iii wider than high (left)/(right), contacting 1 st median ocular, anterior supraciliary, upper preocular, prefrontal/ frontonasal complex, and 1 st and 2 nd loreals (left)/1 st median ocular, anterior supraciliary, upper preocular, and 1 st and 2 nd loreals (right); 10 median oculars (left)/(right), 1 st and 2 nd contacting the prefrontal (left)/(right); 1 upper preocular (left)/(right); an irregular anterior supraciliary (left)/(right); 6 lateral oculars (left)/(right); 5 (left)/4 (1 st fused with FP) (right) temporals; 2 suboculars (left)/(right); posterior subocular large and elongate (left)/(right); anterior subocular small (left)/(right); 9 supralabials (left)/(right), 6 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 a single, slightly larger postmental; 4 pairs of enlarged chin shields, followed by 1 pair of reduced chin shields; 1 st pair in contact with one another anteriorly, posteriorly separated by one scale; 2 nd –5 th pairs separated by 1–5 scales; 92 transverse rows of dorsal scales from interoccipital to base of tail; 92 transverse rows of ventral scales from mental to vent; 39 scales around midbody; 5 digits; finger lengths 3>4>2>5>1; 12 lamellae under longest finger (left)/(right); 38 total lamellae on one hand; toe lengths 4>3>5>2>1; 17 (left)/18 (right) lamellae under longest toe; strigae and median keel dorsal body and caudal scales; faint striations ventral scales; 195 total strigae counted on ten scales.

Color (in alcohol): dorsal surface of head golden tan with some slightly darker brown spots and darker brown areas on scale borders; lateral surfaces of head grading from golden tan to cream with some darker brown areas, especially on the labials and a darker lateral band beginning anterior to the eye; dorsal surfaces of the body are gray-brown with two darker longitudinal paramedian lines that extend halfway down the back, other areas of the back have a regular spotted pattern arranged into chevrons; dorsal surface of tail gray-brown to yellow (on regenerated section); lateral areas grade from gray-brown to white with dark brown and off-white spots arranged in bars; dorsal surfaces of the limbs are bronze with paler spots on them; lateral and ventral areas of the limbs fade to cream; ventral surfaces of the head, body, and tail are pale cream, patternless.

FIGURE 36. (A–F) Comptus alloeides (MCZ R-77152, holotype), SVL 115 mm.

Variation. The examined material overall resembles the holotype in dorsal pattern with all specimens having a pattern of enlarged dots, many of which are continuations of the longitudinal paramedian lines or arranged in broken chevrons. All specimens show longitudinal paramedian lines with the most reduced form occurring in AMNH 40232 . The majority of specimens show patternless heads with the holotype, KU 226562 , and KU 226555 showing some darker outlines on head scale borders and KU 226563 , MCZ R-44398, and USNM 66975 showing irregular, darker markings on their head. The majority of specimens show dots arranged in bars in the lateral band whereas this trait is absent or only present anteriorly in a minority of specimens. Measurements and other morphological data for the holotype and other examined material are presented in Table 1 .

Distribution. Comptus alloeides is known from Peninsula de Samaná and associated islets in the Bahía de Samaná, where it has been collected at elevations of 0–330 m (Fig. 35). It has an extent of occurrence of ~ 790 km 2.

Ecology and conservation. SBH and Richard Thomas collected this species under rocks and among rotting coconut husks and fronds under palm trees (6 km SSW Las Galeras). As with other species confused in the past with Comptus stenurus , this species appears to be tolerant of some habitat disturbance.

We consider the conservation status of Comptus alloeides sp. nov. to be Least Concern, primarily because it has been encountered frequently in the past, based on IUCN Redlist criteria ( IUCN 2023). However, it has a relatively small range, which is of concern. Conversion of forests to agricultural and urban areas will reduce available habitat. Also, introduced predators, including the mongoose and black rats, likely prey upon it. Therefore, studies are needed to determine the health and extent of the populations, and threats to the survival of the species.

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

Etymology. The species name alloeides is derived from the Greek words alloe- (meaning “of a different kind”) and eidos (meaning “form or resemblance”). As noted in the original description ( Schwartz 1964), the name likely alludes to the prominent longitudinal paramedian lines of this species distinguishing this taxon from its close relatives.

Remarks. Large numbers of specimens of this species exist in museum collections. Comptus alloeides is included in our genetic dataset and is placed as the closest relative to C. weinlandi with significant support in ML and Bayesian analyses at the stem node. Based on our timetree (Fig. 4), C. alloeides diverged from its closest relative 1.46 Ma, consistent with typical species of vertebrates (> 0.7 Ma; Hedges et al. 2015). We further recognize it as a distinct species because of the diagnostic trait that separates it from C. weinlandi (the total strigae on ten scales). This species is also sympatric with C. weinlandi at one locality on the Samana Peninsula. Although not diagnostic, the prominent longitudinal paramedian lines that were used to originally identify this species are apparent in all specimens. Comptus alloeides was recovered as conspecific with Comptus weinlandi in our ASAP analysis.