Celestus molesworthi Grant, 1940b

Schools, Molly & Hedges, Blair, 2024, A new forest lizard fauna from Caribbean islands (Squamata, Diploglossidae, Celestinae), Zootaxa 5554 (1), pp. 1-306 : 87-91

Celestus molesworthi Grant, 1940b

Eastern Jamaican Forest Lizard

(Fig. 29–30)

Celestus crusculus molesworthi Grant, 1940b:157 . Holotype: MCZ R-45184, collected by Chapman Grant near Buff Bay , Portland Parish, Jamaica, on 2 May 1937 (18.233, -76.658).

Celestus crusculus molesworthi — Grant, 1940b:104.

Diploglossus crusculus molesworthi — Greer, 1967:96.

Celestus molesworthi — Hedges et al., 2019:17.

Celestus molesworthi — Schools & Hedges, 2021:220.

Celestus molesworthi — Landestoy et al., 2022:205.

Material examined (n=11). JAMAICA. Kingston. MCZ R-45184, Chapman Grant , 2 May 1937 . Portland. BMNH 1970.1741 , Garth Underwood, Priestman’s River ; MCZ R-45185, Chapman Grant, Buff Bay , 2 May 1937 ; USNM 108158–9 , 1 mi S of Buff Bay , 2 May 1939 . Saint Andrew. USNM 117672 , Clydesdale, 6 July 1941 . Saint Thomas. BMNH 1970.1747 , W G. Lynn, Trinityville, Half a Bottle Trail ; BMNH 1965.194 , Morant Point; One of six untagged specimens in one jar : BMNH 1970.1731 – 6 , BMNH 1970.1737 , Garth Underwood, Morant Point ; USNM 326600 , 4.8 mi N of Hordley , 24 July 1981 .

Diagnosis. Celestus molesworthi has (1) a dorsal pattern of dots in chevrons, (2) head markings absent/present, (3) markings in the longitudinal paramedian area absent/present, (4) dots arranged in bars in the lateral band absent/ present, (5) an adult SVL of 78.1–103 mm, (6) ventral scale rows, 102–125, (7) midbody scale rows, 41–49, (8) total lamellae on one hand, 32–44, (9) total strigae on ten scales, 138–159, (10) relative length of all digits on one hindlimb, 22.4–29.4 %, (11) relative distance between the angled subocular and mouth, 0.653 –0.845 %, (12) relative eye length, 3.28–3.70 %, (13) relative forelimb length, 17.5–24.2 %, (14) relative ear width, 1.37–1.50 %, (15) relative rostral height, 1.72–1.81 %, (16) relative head length, 17.2–20.0 %, (17) relative mental width, 1.81–2.00 %, (18) relative postmental width, 2.97–3.08 %, (19) relative cloacal width, 8.73–9.35 %, (20) relative prefrontal width, 4.44–4.90 %, (21) relative largest supraocular width, 1.69–2.80 %, (22) relative longest finger length, 4.28– 5.19 %, (23) relative distance between the ear and eye, 7.97–8.83 %, (24) relative head width, 69.1–76.5 %, (25) relative frontal width, 75.9–95.5 %, (26) relative nasal height, 1.17–1.26 %, (27) relative angled subocular height, 1.11 %, (28) relative distance between the eye and naris, 5.32–5.50 %, (29) relative canthal iii length, 1.99–2.09 %, (30) relative angled subocular width, 2.09–2.48 %, and (31) relative nasal length, 1.55–1.72 %. The species stem time is 4.17 Ma and the species crown time is 0.39 Ma (Fig. 4).

We distinguish Celestus molesworthi from all other species of Celestus based on a complex of traits. From Celestus barbouri , we distinguish C. molesworthi by the dorsal pattern (dots in chevrons versus chevrons), the total strigae on ten scales (138–159 versus 105–136), the relative distance between angled subocular and mouth (0.653 –0.845 versus 0.437 –0.556), the relative rostral height (1.72–1.81 versus 1.41–1.66), the relative head length (17.2–20.0 versus 14.6–16.6), the relative cloacal width (8.73–9.35 versus 7.64–8.26), the relative prefrontal width (4.44–4.90 versus 3.97–4.33), the relative longest finger length (4.28–5.19 versus 2.92–3.81), the relative distance between the ear and eye (7.97–8.83 versus 6.23–7.15), the relative nasal height (1.17–1.26 versus 0.930–1.12), the relative distance between the eye and naris (5.32–5.50 versus 4.68–4.83), and the relative width of canthal iii (1.99– 2.09 versus 1.54–1.93). From C. capitulatus sp. nov., we distinguish C. molesworthi by the relative length of digits on one hindlimb (22.4–29.4 versus 17.6–22.3), the relative cloacal width (8.73–9.35 versus 7.84–8.67), the relative longest finger length (4.28–5.19 versus 3.45–3.75), the relative distance between the ear and eye (7.97–8.83 versus 6.45–7.84), the relative angled subocular height (1.11 versus 0.586–1.01), the relative distance between the eye and naris (5.32–5.50 versus 4.57–5.03), and the relative width of canthal iii (1.99–2.09 versus 1.61–1.70). From C. crusculus , we distinguish C. molesworthi by the adult SVL (78.1–103 versus 59.6–77.6), the relative longest finger length (4.28–5.19 versus 2.94–4.10), and the relative distance between the eye and naris (5.32–5.50 versus 4.31– 4.86). From C. duquesneyi , we distinguish C. molesworthi by the dorsal pattern (dots in chevrons versus bands), the adult SVL (78.1–103 versus 62.1), the total lamellae on one hand (32–44 versus 64), the total strigae on ten scales (138–159 versus 130), the relative length of digits on one hindlimb (22.4–29.4 versus 31.4), the relative distance between angled subocular and mouth (0.653 –0.845 versus 0.644), the relative eye length (3.28–3.70 versus 4.36), the relative forelimb length (17.5–24.2 versus 24.4), the relative ear width (1.37–1.50 versus 2.45), the relative rostral height (1.72–1.81 versus 2.14), and the relative head length (17.2–20.0 versus 21.6). From C. hesperius sp. nov., we distinguish C. molesworthi by the adult SVL (78.1–103 versus 54.0–62.3), the total strigae on ten scales (138–159 versus 95–122), the relative distance between angled subocular and mouth (0.653 –0.845 versus 0.594 –0.648), the relative ear width (1.37–1.50 versus 1.52–1.59), the relative mental width (1.81–2.00 versus 1.51–1.78), the relative postmental width (2.97–3.08 versus 2.87–2.92), the relative cloacal width (8.73–9.35 versus 7.99–8.55), the relative longest finger length (4.28–5.19 versus 3.50–4.04), the relative distance between the ear and eye (7.97–8.83 versus 6.74–7.53), the relative distance between the eye and naris (5.32–5.50 versus 4.70–5.28), and the relative width of canthal iii (1.99–2.09 versus 1.77–1.93). From C. hewardi , we distinguish C. molesworthi by the dorsal pattern (dots in chevrons versus mottled/bands), the adult SVL (78.1–103 versus 129–171), the total lamellae on one hand (32–44 versus 50–61), the total strigae on ten scales (138–159 versus 164–315), and the relative frontal width (75.9–95.5 versus 57.3–75.3). From C. jamesbondi sp. nov., we distinguish C. molesworthi by the adult SVL (78.1–103 versus 54.7–72.0), the relative postmental width (2.97–3.08 versus 2.61–2.92), and the relative distance between the ear and eye (7.97–8.83 versus 6.92–7.80). From C. macrolepis , we distinguish C. molesworthi by the dorsal pattern (dots in chevrons versus bicolored), the adult SVL (78.1–103 versus 254–316), the total lamellae on one hand (32–44 versus 52–54), the total strigae on ten scales (138–159 versus 398), the relative distance between angled subocular and mouth (0.653 –0.845 versus 1.39–1.66), the relative forelimb length (17.5–24.2 versus 26.1–26.7), and the relative longest finger length (4.28–5.19 versus 5.47–5.51). From C. macrotus , we distinguish C. molesworthi by the dorsal pattern (dots in chevrons versus chevrons/bands), the ventral scale rows (102–125 versus 87–93), the total strigae on ten scales (138–159 versus 64–115), the relative length of digits on one hindlimb (22.4–29.4 versus 30.2–31.2), the relative eye length (3.28–3.70 versus 3.79–5.17), the relative ear width (1.37–1.50 versus 1.75–2.08), the relative largest supraocular width (1.69–2.80 versus 2.96–4.03), the relative longest finger length (4.28–5.19 versus 6.43–6.67), the relative frontal width (75.9–95.5 versus 57.6–66.1), the relative angled subocular height (1.11 versus 1.00–1.07), the relative angled subocular width (2.09–2.48 versus 2.77–2.83), and the relative nasal width (1.55–1.72 versus 2.08–2.33). From C. microblepharis , we distinguish C. molesworthi by the dorsal pattern (dots in chevrons versus chevrons), the total lamellae on one hand (32–44 versus 30), the total strigae on ten scales (138–159 versus 165), the relative length of digits on one hindlimb (22.4–29.4 versus 16.6), the relative eye length (3.28–3.70 versus 1.83), the relative forelimb length (17.5–24.2 versus 14.2), the relative ear width (1.37– 1.50 versus 0.446), the relative rostral height (1.72–1.81 versus 1.71), the relative head length (17.2–20.0 versus 14.7), and the relative nasal height (1.17–1.26 versus 0.726). From C. occiduus , we distinguish C. molesworthi by the dorsal pattern (dots in chevrons versus absent), the adult SVL (78.1–103 versus 269–367), the total lamellae on one hand (32–44 versus 50–66), the total strigae on ten scales (138–159 versus 374), the relative distance between angled subocular and mouth (0.653 –0.845 versus 1.26–1.27), the relative head length (17.2–20.0 versus 20.4–20.6), and the relative distance between the ear and eye (7.97–8.83 versus 8.98–10.9). From C. oligolepis sp. nov., we distinguish C. molesworthi by the ventral scale rows (102–125 versus 98), the midbody scale rows (41–49 versus 35), and the total lamellae on one hand (32–44 versus 30). From C. striatus , we distinguish C. molesworthi by the dorsal pattern (dots in chevrons versus absent/chevrons), the adult SVL (78.1–103 versus 145), the total lamellae on one hand (32–44 versus 59–66), the total strigae on ten scales (138–159 versus 279), the relative length of digits on one hindlimb (22.4–29.4 versus 37.8), the relative eye length (3.28–3.70 versus 3.85), the relative forelimb length (17.5–24.2 versus 26.1), the relative ear width (1.37–1.50 versus 1.30), the relative rostral height (1.72–1.81 versus 1.94).

Description of holotype. MCZ R-45184. An adult; SVL 85.6 mm; tail nearly cylindrical, 82.0 mm (95.8% SVL); axilla-to-groin distance 47.5 mm (55.5% SVL); forelimb length 15.0 mm (17.5% SVL); hindlimb length 25.9 mm (30.3% SVL); head length 15.8 mm (18.5% SVL); head width 12.1 mm (14.1% SVL); head width 76.6% head length; diameter of orbit 2.82 mm (3.29% SVL); horizontal diameter of ear opening 1.28 mm (1.50% SVL); vertical diameter of ear opening 1.49 mm (1.74% SVL); length of all toes on one foot 20.3 mm (23.7% SVL); shortest distance between angled subocular and lip 0.87 mm (1.02% SVL); shortest distance between the ocular and auricular openings 6.82 mm (7.97% SVL); longest finger length 3.66 mm (4.28% SVL); largest supraocular width 1.45 mm (1.69% SVL); cloacal width 8.00 mm (9.35% SVL); mental width 1.71 mm (2.00% SVL); postmental width 2.54 mm (2.97% SVL); prefrontal width 3.80 mm (4.44% SVL); frontal width 95.5% frontal length; nasal height 1.00 mm (1.17% SVL); angled subocular height 0.95 mm (1.11% SVL); shortest distance between the eye and naris 4.55 mm (5.32% SVL); canthal iii width 1.79 mm (2.09% SVL); angled subocular width 1.79 mm (2.09% SVL); nasal width 1.33 mm (1.55% 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, much wider than long, bordered by posterior internasals, 1 st loreals, canthal iii, 1 st 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 approximately the size of parietals and separating them, posteriorly touching the interoccipital, which is wider than long; parietal separated from supraoculars by 1 st temporals and frontoparietal (left)/(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 –4th supralabials (left)/(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)/(right); 10 median oculars (left)/(right), 1 st contacting the prefrontal (left)/(right); 1 upper preocular (left)/(right); an irregular anterior supraciliary (left)/(right); 7 (left)/6 (right) lateral oculars; 5 temporals (left)/(right); 2 suboculars (left)/ (right); posterior subocular large and elongate (left)/(right); anterior subocular small (left)/(right); 10 (left)/9 (right) supralabials, 6 to level below center of eye (left)/(right); 10 (left)/9 (right) infralabials, 6 to level below center of eye (left)/(right); mental small, followed by a single, slightly larger postmental; 4 pairs of enlarged chin shields; 1 st pair in contact with one another; 2 nd to 4 th pair separated by 1–3 scales; 115 transverse rows of dorsal scales from interoccipital to base of tail; 119 transverse rows of ventral scales from mental to vent; 46 scales around midbody; 5 digits; finger lengths 3>4>2>5>1; 8 (right) lamellae under longest finger; 34 total lamellae on one hand; toe lengths 4>3>5>2>1; 15 (left)/14 (right) lamellae under longest toe; striate with a faint median keel dorsal body and caudal scales; smooth to faintly striated ventral scales; 138 total strigae counted on ten scales.

Color (in alcohol): dorsal surface of head a golden tan, patternless; lateral surfaces of head grading from golden tan to dark cream with darker brown eye masks and areas on the labial scales; dorsal surfaces of the body are a pale tan with medium brown chevrons; dorsal surface of tail same as the body with the chevrons of the body disappearing after the base; lateral areas grade from dark brown around the forelimb to pale tan down the rest of the side that is interspersed with regular medium brown and white dots that are continuations of the chevrons from the back that appear as vertical or diagonal lines down the sides; dorsal surfaces of the limbs are medium brown with paler gold spots; lateral and ventral areas of the limbs fade to cream; ventral surfaces of the head, body, and tail are pale cream, patternless.

FIGURE 29. (A–F) Celestus molesworthi (MCZ R-45184, holotype), SVL 85.6 mm. FIGURE 30. Celestus molesworthi (USNM 328144, SBH 172465), in life. From 1.3 km WSW Section, Portland Parish, Jamaica. Photo by SBH.

Variation. The examined material resembles the dorsal pattern of the holotype with dots arranged in broken chevrons. Specimens have both patternless heads or exhibit head scales with darker outlines. Markings in the longitudinal paramedian series range from absent, to mottling, to broken longitudinal paramedian lines, to present longitudinal paramedian lines. Measurements and other morphological data for the holotype and other examined material are presented in Table 1.

Distribution. Celestus molesworthi is distributed on the coast and in inland areas of northeastern Jamaica at elevations of 0–960 m (Fig. 12).

Ecology and conservation. The original description of this species reported that individuals were recovered from under rotting piles of coconut husks ( Grant 1940b). Grant (1940a) also noted that as an escape mechanism, this species will “wriggle with astonishing speed,” but will not use its legs.

We consider the conservation status of Celestus molesworthi to be Endangered B1ab(iii,v) because “the species has a small extent of occurrence (around 1330 km 2), and is inferred to occur in only a single location and to be undergoing continuing decline in the extent and quality of its habitat and the number of mature individuals (based on the prevalence of conversion of moist forest habitat to residential and tourism developments, and the depredations of mongoose and cats, throughout its small range),” based on IUCN Redlist criteria ( IUCN 2023). Studies are needed to determine the health and extent of remaining populations and threats to the survival of the species. Captive-breeding programs should be undertaken, because eradication of introduced mammalian predators is not yet possible on Jamaica.

Reproduction. Little data exist on the reproduction of this species. One neonate SVL 26 mm, tail 30 mm was recorded ( Grant 1940a).

Etymology. The species was named for Mr. Delves Molesworth, who served as the Secretary of the Institute of Jamaica from 1936–1938.

Remarks. Celestus molesworthi was originally described as a subspecies of C. crusculus ( C. crusculus molesworthi ) ( Grant 1940b) but was referred to as a full species in later works ( Hedges et al. 2019; Hedges 2023). Sexual dimorphism was reported in this species with males recorded as having “thicker, heavier heads,” in addition to being “apparently somewhat larger” than females ( Grant 1940a).

Celestus molesworthi is included in our genetic dataset and has significant support in both Bayesian and ML likelihood analyses at the crown node for the species. The stem node that places it as the closest relative to C. duquesneyi and C. hewardi has a support value of 84% in ML analyses and 83% in Bayesian analyses. Genomic data in Schools et al. (2022) placed C. molesworthi (referred to as C. cundalli ) as the closest relative to C. duquesneyi with a support value of 52% in ML analyses and a significant value in Bayesian analyses. Based on our timetree (Fig. 4), C. molesworthi diverged from its closest relative 4.17 Ma, consistent with typical species of vertebrates (> 0.7 Ma; Hedges et al. 2015). Celestus molesworthi was recognized as a distinct species in our ASAP analysis.