Celestus occiduus ( Shaw 1802 )

Schools, Molly & Hedges, Blair, 2024, A new forest lizard fauna from Caribbean islands (Squamata, Diploglossidae, Celestinae), Zootaxa 5554 (1), pp. 1-306 : 92-97

Celestus occiduus ( Shaw 1802)

Yellow Giant Forest Lizard

(Fig. 31)

Lacerta Occidua Shaw, 1802:288 . Holotype: BMNH XV.115A.

Scincus gallivasp — Daudin, 1802:239. Syntypes: MNHN-RA-0.1227, from Jamaica .

Diploglossus Shawii — Duméril & Bibron, 1839:590. Syntypes: MNHN-RA-0.1227, from Jamaica. Diploglossus occiduus — Boulenger, 1885:290.

Diploglossus impressus — Boulenger, 1885:291.

Macrogongylus brauni — Werner, 1901:299. Holotype: unknown, from Jamaica.

Celestus impressus — Barbour, 1910:298.

Celestus occiduus — Barbour, 1930:100.

Celestus occiduus — Barbour, 1935:123.

Celestus occiduus — Barbour, 1937:139.

Celestus occiduus occiduus — Grant, 1940a:108.

Celestus occiduus — Schwartz & Henderson, 1991:378.

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

Celestus occiduus — Schools & Hedges, 2021:220.

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

Material examined (n=6). JAMAICA. ANSP 9776 ; BMNH 1970.1816 ; BMNH XV.115.A; MCZ R-131774, Ex. Army Medical College, 28 December 1938. Manchester . USNM 102652 , Kensworth, near Newport, 23 February 1937. Saint Elizabeth . USNM 73272 , Balaclava, 1914.

Diagnosis. Celestus occiduus has (1) a dorsal pattern of absent, (2) head markings absent, (3) markings in the longitudinal paramedian area absent, (4) dots arranged in bars in the lateral band absent, (5) an adult SVL of 269– 367 mm, (6) ventral scale rows, 109–134, (7) midbody scale rows, 46–56, (8) total lamellae on one hand, 50–66, (9) total strigae on ten scales, 374, (10) relative length of all digits on one hindlimb, 24.4–29.7 %, (11) relative distance between the angled subocular and mouth, 1.26–1.27 %, (12) relative eye length, 2.87–3.33 %, (13) relative forelimb length, 23.5–23.9 %, (14) relative ear width, 0.948–1.39 %, (15) relative rostral height, 1.60–1.83 %, (16) relative head length, 20.4–20.6 %, (17) relative mental width, 1.86 %, (18) relative postmental width, 3.57 %, (19) relative cloacal width, 9.00 %, (20) relative prefrontal width, 4.76 %, (21) relative largest supraocular width, 2.27–3.02 %, (22) relative longest finger length, 4.77–5.46 %, (23) relative distance between the ear and eye, 8.98–10.9 %, (24) relative head width, 73.8 %, (25) relative frontal width, 63.8 %, (26) relative nasal height, 1.16 %, (27) relative angled subocular height, 1.30 %, (28) relative distance between the eye and naris, 6.51 %, (29) relative canthal iii length, unavailable, (30) relative angled subocular width, 2.52 %, and (31) relative nasal length, 1.83 %. The species stem time is 3.49 Ma and the species crown time is 0.41 Ma (Fig. 4).

Celestus occiduus differs from all but one other member of the genus ( C. striatus ) in lacking a dorsal pattern. This species also has a larger SVL (269–367), number of total strigae on ten scales (374), relative distance between the angled subocular and mouth (1.26–1.27), and relative distance between the eye and naris (6.51) than most other species of the genus.

From Celestus barbouri , we distinguish C. occiduus by the dorsal pattern (absent versus chevrons), the adult SVL (269–367 versus 78.4–93.6), the total lamellae on one hand (50–66 versus 36–49), the total strigae on ten scales (374 versus 105–136), the relative length of digits on one hindlimb (24.4–29.7 versus 18.2–23.5), the relative distance between angled subocular and mouth (1.26–1.27 versus 0.437 –0.556), the relative forelimb length (23.5– 23.9 versus 15.4–19.0), the relative head length (20.4–20.6 versus 14.6–16.6), the relative mental width (1.86 versus 1.51–1.85), the relative postmental width (3.57 versus 2.51–3.29), the relative cloacal width (9.00 versus 7.64– 8.26), the relative prefrontal width (4.76 versus 3.97–4.33), the relative longest finger length (4.77–5.46 versus 2.92–3.81), the relative distance between the ear and eye (8.98–10.9 versus 6.23–7.15), the relative frontal width (63.8 versus 65.6–82.1), the relative nasal height (1.16 versus 0.930–1.12), the relative angled subocular height (1.30 versus 0.553–1.16), the relative distance between the eye and naris (6.51 versus 4.68–4.83), and the relative nasal width (1.83 versus 1.38–1.65). From C. capitulatus sp. nov., we distinguish C. occiduus by the dorsal pattern (absent versus irregular dots/dots in chevrons), the adult SVL (269–367 versus 62.1–81.8), the total lamellae on one hand (50–66 versus 25–38), the total strigae on ten scales (374 versus 105–192), the relative length of digits on one hindlimb (24.4–29.7 versus 17.6–22.3), the relative distance between angled subocular and mouth (1.26–1.27 versus 0.525–1.17), the relative forelimb length (23.5–23.9 versus 14.3–18.1), the relative head length (20.4–20.6 versus 15.1–17.7), the relative mental width (1.86 versus 1.28–1.84), the relative postmental width (3.57 versus 2.62–2.97), the relative cloacal width (9.00 versus 7.84–8.67), the relative prefrontal width (4.76 versus 4.30–4.72), the relative longest finger length (4.77–5.46 versus 3.45–3.75), the relative distance between the ear and eye (8.98–10.9 versus 6.45–7.84), the relative frontal width (63.8 versus 78.1–81.6), the relative angled subocular height (1.30 versus 0.586–1.01), the relative distance between the eye and naris (6.51 versus 4.57–5.03), and the relative angled subocular width (2.52 versus 1.93–2.32). From C. crusculus , we distinguish C. occiduus by the longitudinal paramedian lines (absent versus present), the adult SVL (269–367 versus 59.6–77.6), the midbody scale rows (46– 56 versus 37–44), the total lamellae on one hand (50–66 versus 30–39), the total strigae on ten scales (374 versus 106–194), the relative distance between angled subocular and mouth (1.26–1.27 versus 0.339 –0.884), the relative forelimb length (23.5–23.9 versus 12.8–20.7), the relative head length (20.4–20.6 versus 15.5–20.3), the relative postmental width (3.57 versus 2.73–3.37), the relative cloacal width (9.00 versus 6.89–8.77), the relative prefrontal width (4.76 versus 3.93–4.67), the relative longest finger length (4.77–5.46 versus 2.94–4.10), the relative distance between the ear and eye (8.98–10.9 versus 6.07–8.61), the relative frontal width (63.8 versus 82.6–91.1), the relative angled subocular height (1.30 versus 0.953–1.21), the relative distance between the eye and naris (6.51 versus 4.31–4.86), the relative angled subocular width (2.52 versus 2.03–2.43), and the relative nasal width (1.83 versus 1.27–1.60). From C. duquesneyi , we distinguish C. occiduus by the dorsal pattern (absent versus bands), the adult SVL (269–367 versus 62.1), the total strigae on ten scales (374 versus 130), and the relative ear width (0.948–1.39 versus 2.45). From C. hesperius sp. nov., we distinguish C. occiduus by the dorsal pattern (absent versus dots in chevrons), the adult SVL (269–367 versus 54.0–62.3), the midbody scale rows (46–56 versus 39–44), the total lamellae on one hand (50–66 versus 29–34), the total strigae on ten scales (374 versus 95–122), the relative distance between angled subocular and mouth (1.26–1.27 versus 0.594 –0.648), the relative eye length (2.87–3.33 versus 3.61–3.74), the relative forelimb length (23.5–23.9 versus 18.6–21.3), the relative ear width (0.948–1.39 versus 1.52–1.59), the relative head length (20.4–20.6 versus 15.7–17.7), the relative largest supraocular width (2.27–3.02 versus 1.91–2.22), the relative longest finger length (4.77–5.46 versus 3.50–4.04), and the relative distance between the ear and eye (8.98–10.9 versus 6.74–7.53). From C. hewardi , we distinguish C. occiduus by the dorsal pattern (absent versus mottled/bands), the adult SVL (269–367 versus 129–171), the total strigae on ten scales (374 versus 164–315), the relative ear width (0.948–1.39 versus 1.40–1.82), the relative mental width (1.86 versus 1.75–1.81), the relative postmental width (3.57 versus 2.84–3.44), the relative distance between the ear and eye (8.98–10.9 versus 6.72–8.73), the relative nasal height (1.16 versus 1.21–1.24), the relative distance between the eye and naris (6.51 versus 5.00–5.60), and the relative angled subocular width (2.52 versus 1.63–2.23). From C. jamesbondi sp. nov., we distinguish C. occiduus by the adult SVL (269–367 versus 54.7–72.0), the midbody scale rows (46–56 versus 35–44), the total lamellae on one hand (50–66 versus 30–36), the total strigae on ten scales (374 versus 101–173), the relative distance between angled subocular and mouth (1.26–1.27 versus 0.363–1.01), the relative forelimb length (23.5–23.9 versus 14.4–19.9), the relative postmental width (3.57 versus 2.61–2.92), the relative longest finger length (4.77–5.46 versus 3.66–4.33), the relative distance between the ear and eye (8.98–10.9 versus 6.92–7.80), the relative head width (73.8 versus 76.0–80.8), the relative frontal width (63.8 versus 70.5–77.6), the relative angled subocular height (1.30 versus 0.893–1.18), the relative distance between the eye and naris (6.51 versus 4.25–5.54), and the relative nasal width (1.83 versus 1.42–1.75). From C. macrolepis , we distinguish C. occiduus by the dorsal pattern (absent versus bicolored), the relative distance between angled subocular and mouth (1.26–1.27 versus 1.39–1.66), the relative eye length (2.87–3.33 versus 3.63–3.70), the relative forelimb length (23.5–23.9 versus 26.1–26.7), and the relative longest finger length (4.77–5.46 vs 5.47–5.51). From C. macrotus , we distinguish C. occiduus by the dorsal pattern (absent versus chevrons/bands), the longitudinal paramedian lines (absent versus present), the dots arranged in bars in the lateral areas (absent versus present), the adult SVL (269–367 versus 60.0–86.1), the ventral scale rows (109–134 versus 87–93), the midbody scale rows (46–56 versus 41–45), the total lamellae on one hand (50–66 versus 39–40), the total strigae on ten scales (374 versus 64–115), the relative length of digits on one hindlimb (24.4–29.7 versus 30.2–31.2), the relative distance between angled subocular and mouth (1.26–1.27 versus 0.640 –0.983), the relative eye length (2.87–3.33 versus 3.79–5.17), the relative ear width (0.948–1.39 versus 1.75–2.08), the relative longest finger length (4.77–5.46 versus 6.43–6.67), the relative distance between the ear and eye (8.98–10.9 versus 7.58–8.02). From C. microblepharis , we distinguish C. occiduus by the dorsal pattern (absent versus chevrons), the adult SVL (269–367 versus 96.4), the midbody scale rows (46–56 versus 43), the total lamellae on one hand (50–66 versus 30), the total strigae on ten scales (374 versus 165), the relative distance between angled subocular and mouth (1.26–1.27 versus 0.820), the relative eye length (2.87–3.33 versus 1.83), the relative forelimb length (23.5–23.9 versus 14.2), the relative ear width (0.948–1.39 versus 0.446), the relative nasal height (1.16 versus 0.726), and the relative angled subocular height (1.30 versus 0.778). From C. molesworthi , we distinguish C. occiduus by the dorsal pattern (absent versus dots in chevrons), the adult SVL (269–367 versus 78.1–103), the total lamellae on one hand (50–66 versus 32–44), the total strigae on ten scales (374 versus 138–159), the relative distance between angled subocular and mouth (1.26–1.27 versus 0.653 –0.845), the relative head length (20.4–20.6 versus 17.2–20.0), the relative distance between the ear and eye (8.98–10.9 versus 7.97–8.83). From C. oligolepis sp. nov., we distinguish C. occiduus by the dorsal pattern (absent versus dots in chevrons), the head markings (absent versus present), the longitudinal paramedian lines (absent versus present), the ventral scale rows (109–134 versus 98), the midbody scale rows (46–56 versus 35), and the total lamellae on one hand (50–66 versus 30). From C. striatus , we distinguish C. occiduus by the adult SVL (269–367 versus 145), the midbody scale rows (46–56 versus 41–43), and the relative distance between angled subocular and mouth (1.26– 1.27 versus 0.710).

Description of holotype. BMNH XV.115A. An adult; SVL 269 mm; tail laterally compressed, broken, 172 mm (63.9% SVL); axilla-to-groin distance 138 mm (51.3% SVL); forelimb length 63.3 mm (23.5% SVL); hindlimb length 91.8 mm (34.1% SVL); head length 54.9 mm (20.4% SVL); head width 40.5 mm (15.1% SVL); head width 73.8% head length; diameter of orbit 8.95 mm (3.33% SVL); horizontal diameter of ear opening 2.55 mm (0.948% SVL); vertical diameter of ear opening 5.16 mm (1.92% SVL); length of all toes on one foot 80.0 mm (29.7% SVL); shortest distance between angled subocular and lip 3.40 mm (1.26% SVL); shortest distance between the ocular and auricular openings 24.2 mm (9.00% SVL); longest finger length 14.7 mm (5.46% SVL); largest supraocular width 8.12 mm (3.02% SVL); cloacal width 24.2 mm (9.00% SVL); mental width 5.01 mm (1.86% SVL); postmental width 9.60 mm (3.57% SVL); prefrontal width 12.8 mm (4.76% SVL); frontal width 63.8% frontal length; shortest distance between eye and naris 17.5 mm (6.51% SVL); angled subocular width 6.78 mm (2.52% SVL); nasal width 4.92 mm (1.83% SVL); rostral 1.60X 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 concave posterior margin, wider than long, bordered by posterior internasals, 1 st loreals, 1 st and 2 nd median oculars, and the frontal; frontal much longer than wide; a pair of frontoparietals (left fused with frontal), separated by the interparietal plate; interparietal plate much smaller than parietals and separating them (missing), posteriorly touching the interoccipital, which is approximately as wide as long; parietal separated from supraoculars by fused frontal/frontoparietal/uppermost temporal complex (left)/ 1 st and 2 nd temporals and frontoparietal (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, 1 st median ocular, canthal iii, 2 nd loreal, and 3 rd –5 th 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); final loreal posteriorly bordering the lower preocular (left)/(right); canthal iii wider than high (left)/divided into two scales, together are wider than high (right), contacting 1 st median ocular, anterior supraciliary, lower preocular, and 1 st and 2 nd loreals (left)/(right); 8 (left)/9 (right) median oculars, 1 st and 2 nd contacting the prefrontal (left)/(right); 0 upper preoculars (left)/(right); an irregular anterior supraciliary (left)/(right); 6 lateral oculars (left)/(right); 5 (several are fused) (left)/5 (right) temporals; 2 suboculars (left)/(right); posterior subocular large and elongate (left)/(right); anterior subocular small (left)/(right); 11 supralabials (left)/ (right), 7 (left)/8 (right) to level below center of eye; mental small, followed by a single, larger postmental; 5 pairs of enlarged chin shields; 1 st pair in contact with one another; 2 nd –5 th pairs separated by 1–5 scales; 128 transverse rows of dorsal scales from interoccipital to base of tail; 124 transverse rows of ventral scales from mental to vent; 48 scales around midbody; 5 digits; finger lengths 3>4>2>5>1; 17 lamellae under longest finger (left)/(right); 66 total lamellae on one hand; toe lengths 4>3>5>2>1; 23(right) lamellae under longest toe; dorsal body and caudal scales striate with a faint median keel; smooth ventral scales; 374 total strigae counted on ten scales.

Color (in alcohol): dorsal surface of head dark gold with some darker brown areas; lateral surfaces of head grading from dark gold to creamy yellow, patternless; dorsal surfaces of the body are dark gold, patternless; dorsal surface of tail the same dark gold as the head; lateral areas grade from the same dark gold as the head to creamy yellow; dorsal surfaces of the limbs are dark gold; lateral and ventral areas of the limbs fade to creamy yellow; ventral surfaces of the head, body, and tail are yellow-cream, patternless.

Variation. The examined material closely resembles the holotype in a lack of pattern. Measurements and other morphological data for the holotype and other examined material are presented in Table 1.

Distribution. Little data are available on the distribution of Celestus occiduus as most specimen accounts give either no information or refer to “West Indies” or “ Jamaica ” as the area from which the specimens were collected. Gosse (1851) has previously referred to this species as the “Morass Galliwasp,” indicating that it was from the area of the Black River on the southwestern coast of Jamaica (Fig. 11).

Ecology and conservation. Based on literature reports, Celestus occiduus is a swamp-dwelling lizard.Although confusion has persisted throughout the literature regarding the identification of C. occiduus , ecological reports of a yellow diploglossid (presumably C. occiduus ) living in the Jamaican swamps confirm its placement in the Swamp Ecomorph. Gosse (1851: 77) described the “Yellow Galliwasp” as occurring in the “swamps and morasses of Westmoreland Parish,” where it “might be observed sitting idly in the mouth of its burrow, or feeding on the wild fruits and marshy plants that constitute its food.” Later in the book ( Gosse 1851: 214), he mentioned that C. occiduus eats fruit from the Alligator Apple tree ( Annona paulustris ), which occurs in and around the same morasses. This descriptive yellow color of C. occiduus agrees more closely with the holotype, a pale specimen in preservative, than with the holotype of C. macrolepis , a specimen that is predominantly dark brown, with pale blotches ( Schools & Hedges 2021: fig. 12). As reported by the naturalist Anthony Robinson during the 1760s (in Cockerell 1894), the species “ Celestus occiduus ” was observed to hunt for fish from riverbanks, from which they would jump into the water to catch fish and return with them to the riverbanks. When discussing C. occiduus, Shaw (1802) commented that the back teeth of the species resemble the molars of mammals. This might be an adaptation for eating hard invertebrates, such as the crabs found in the stomach of C. macrolepis , an association noted in other species of lizards ( Renesto & Dalla Vecchia 2000).

The IUCN Redlist ( IUCN 2023) considers the conservation status of Celestus occiduus to be Critically Endangered (Possibly Extinct) C2a(i,ii); D because it was “last recorded in the mid-nineteenth century, it is thought that the introduction of predatory species (primarily mongoose) to Jamaica, and the extensive conversion of woody swamp habitat, resulted in the extinction of C. occiduus . Recent surveys, although extensive, have not yet been exhaustive, given the difficulties of access into and around the Black River Morass, leaving room for some hope that the species may persist, albeit with a tiny population. Any remnant population is thought likely to number fewer than 50 mature individuals of this large species and is likely to be restricted to a very small area likely at risk from habitat degradation and continued impacts of mongoose predation.” Studies are needed to determine the health and extent 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 is Latin meaning western, presumably for its distribution in western Jamaica (or at least west of the major population area of Jamaica, Kingston).

Remarks. Celestus occiduus , first described in 1802, has had a long and confusing taxonomic history, especially because of its confusion with C. macrolepis . Cochran (1941) also suggested that C. crusculus may in fact be juvenile C. occiduus , a hypothesis that can be discounted because many adult specimens (including gravid females) of C. crusculus , a much smaller species, exist.

Grant (1951) said that he believed that Celestus impressus is a synonym of C. occiduus . However, Schwartz (1964) reported that one syntype of C. impressus , which he designated as lectotype (ANSP 9225), was C. hewardi and the other was C. crusculus . We examined those specimens and agree with Schwartz, although the damage to both specimens is substantial.

Cousens (1956) reported that a giant Galliwasp had not been seen in over 100 years; however, Grant (1940a) suspected that Celestus occiduus could still exist. Later, Schwartz (1970) said that he found it highly unlikely that the species could still exist, and speculated that C. barbouri , C. crusculus , C. hewardi , and C. occiduus might form a group. Since the introduction of the mongoose, many species, including C. occiduus , likely were more widespread, but are now found only in the highlands ( Barbour 1910). If this is the case, C. occiduus , a swamp dweller, might not have been able to find refuge in the highlands, in contrast to the other species.

FIGURE 31. (A–F) Celestus occiduus (BMNH XV.115A, holotype), SVL 269 mm.

The holotype number of Celestus occiduus was incorrectly reported as BMNH XV.118A by Schwartz & Henderson (1991) and Schools & Hedges (2021). This presumably was a result of the confusion of C. macrolepis with C. occiduus , and, because the holotype number for C. macrolepis is BMNH XV.118.A or 1946.8.3.82. The correct holotype number for C. occiduus is BMNH XV.115.A and the Natural History Museum has made that correction on the specimen tag as well.

Celestus occiduus (two individuals) is included in our genetic dataset and has significant support in both Bayesian and ML likelihood analyses at the crown node of the species and the stem node that places it as the closest relative to C. striatus . Based on our timetree (Fig. 4), C. occiduus diverged from its closest relative 3.49 Ma, consistent with typical species of vertebrates (> 0.7 Ma; Hedges et al. 2015). Celestus occiduus was recognized as a distinct species in our ASAP analysis.