Panolopus oreistes ( Schwartz 1964 )

Schools, Molly & Hedges, Blair, 2024, A new forest lizard fauna from Caribbean islands (Squamata, Diploglossidae, Celestinae), Zootaxa 5554 (1), pp. 1-306 : 200-204

Panolopus oreistes ( Schwartz 1964)

Dark Spotted Forest Lizard

(Fig. 73–74)

Diploglossus costatus oreistes Schwartz, 1964:25 . Holotype: MCZ R-74940, collected by George Whiteman from Oriani, near Saltrou, Ouest department, Haiti, between 21 March and 20 June 1962 (18.317, -71.933; 1,544 m).

Celestus costatus oreistes — Schwartz & Henderson, 1988:96.

Celestus costatus oreistes — Schwartz & Henderson, 1991:367.

Celestus costatus oreistes — Hedges et al., 2019:16.

Panolopus costatus oreistes — Schools & Hedges, 2021:230.

Material examined (n=53). DOMINICAN REPUBLIC. Barahona. KU 225401 , 3 km N Enriquillo , 8 August 1975 ; KU 225410 , 3 km N, 15 km SW Barahona , 20 June 1969 . Independencia. ANSP 38609–12 , Puerto Escondido , 20.8 km SE of, 23 July 1991 ; ANSP 38613–4 , Puerto Escondido , 23.1 km SE of, 23 July 1991 ; ANSP 38615–21 , Puerto Escondido , 23.9 km SE of, 25 July 1991 ; KU 225415 , El Aguacate, 1969 ; SBH 192496 , S. Blair Hedges, Richard Thomas, and Nicholas Plummer, 23.9 km SE of Puerto Escondido , 23 July 1991 . Pedernales. ANSP 38598–606 , Casetta Dos, Aceitillar, ca. 22 km N of, by road on ridge of Sierra de Bahoruco , 19 November 2009 . HAITI. Ouest. ANSP 38585–96 , S. Blair Hedges, Richard Thomas, Elizabeth Rochel, Eladio Fernandez, Berry , 19 November 2009 ; ANSP 38597 , 1.0 km SW Berry, 19 November 2009 ; KU 225509 , Peneau, 6 July 1962 ; KU 225513 , 225515 , Furcy, 8 July 1962 ; SBH 268567 , 1.0 km SW Berry, 19 November 2009 ; SBH 268583 , 268590 , S. Blair Hedges, Richard Thomas, Elizabeth Rochel, Eladio Fernandez, Berry , 19 November 2009 . Sud-Est. ANSP 38607–8 , Morne D’Enfer, southwestern edge of plateau, 21 November 2011 ; KU 225520 , Foret des Pins , 12 August 1962 ; KU 225522 , Foret des Pins , 25 November 1972 ; KU 225531 , Thiotte, 8 August 1976 ; MCZ R-74939, R-74940, R-74941, George Whiteman, Oriani, near Saltrou , 21 March–20 June 1962 .

Diagnosis. Panolopus oreistes 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 present, (5) an adult SVL of 77.3–103 mm, (6) ventral scale rows, 80–104, (7) midbody scale rows, 35–43, (8) total lamellae on one hand, 39–55, (9) total strigae on ten scales, 155–267, (10) relative length of all digits on one hindlimb, 31.2–40.1 %, (11) relative distance between the angled subocular and mouth, 0.406 – 0.865 %, (12) relative eye length, 3.03–3.67 %, (13) relative forelimb length, 20.1–24.9 %, (14) relative ear width, 0.558–1.79 %, (15) relative rostral height, 1.82–2.88 %, (16) relative head length, 15.3–19.8 %, (17) relative mental width, 1.54–1.90 %, (18) relative postmental width, 2.18–3.19 %, (19) relative cloacal width, 7.13–8.78 %, (20) relative prefrontal width, 4.18–4.96 %, (21) relative largest supraocular width, 2.28–3.23 %, (22) relative longest finger length, 5.27–7.23 %, (23) relative distance between the ear and eye, 6.29–9.50 %, (24) relative head width, 66.1–85.0 %, (25) relative frontal width, 61.6–76.9 %, (26) relative nasal height, 0.878–1.06 %, (27) relative angled subocular height, 0.737 –0.978 %, (28) relative distance between the eye and naris, 5.01–5.63 %, (29) relative canthal iii length, 1.61–2.16 %, (30) relative angled subocular width, 2.13–3.04 %, and (31) relative nasal length, 1.37–1.65 %. The species stem time is 2.43 Ma and the species crown time is 0.77 Ma (Fig. 4).

We distinguish Panolopus oreistes from the other species of Panolopus based on a complex of traits. From Panolopus aenetergum , we distinguish P. oreistes by the longitudinal paramedian lines (present versus absent), the relative length of digits on one hindlimb (31.2–40.1 versus 26.8), the relative prefrontal width (4.18–4.96 versus 4.15), the relative longest finger length (5.27–7.23 versus 4.83), the relative frontal width (61.6–76.9 versus 88.2), the relative nasal height (0.878–1.06 versus 1.15), the relative angled subocular height (0.737 –0.978 versus 1.08), the relative distance between the eye and naris (5.01–5.63 versus 4.35), the relative angled subocular width (2.13– 3.04 versus 2.07), and the relative nasal width (1.37–1.65 versus 1.92). From P. aporus , we distinguish P. oreistes by the relative nasal height (0.878–1.06 versus 1.08–1.23). From P. chalcorhabdus , we distinguish P. oreistes by the relative nasal width (1.37–1.65 versus 1.70–2.01). From P. costatus , we distinguish P. oreistes by the area of the nasal scale by the SVL (1.06–1.57 versus 1.59–2.03) (see Remarks). From P. curtissi , we distinguish P. oreistes by the dorsal pattern (irregular dots/dots in series/dots in chevrons versus absent/irregular flecks), the dots arranged in bars in the lateral areas (present versus absent), the relative length of digits on one hindlimb (31.2–40.1 versus 20.8–28.1), and the relative longest finger length (5.27–7.23 versus 3.59–4.54). From P. diastatus , we distinguish P. oreistes by the dorsal pattern (irregular dots/dots in series/dots in chevrons versus absent/irregular flecks), the longitudinal paramedian lines (present versus absent), the relative length of digits on one hindlimb (31.2–40.1 versus 21.5–27.4), the relative longest finger length (5.27–7.23 versus 3.48–4.87), and the relative distance between the eye and naris (5.01–5.63 versus 4.06–4.94). From P. emys , we distinguish P. oreistes by the dorsal pattern (irregular dots/dots in series/ dots in chevrons versus absent/irregular flecks). From P. hylonomus , we distinguish P. oreistes by the dorsal pattern (irregular dots/dots in series/dots in chevrons versus absent/irregular flecks), the dots arranged in bars in the lateral areas (present versus absent), the adult SVL (77.3–103 versus 59.3–76.5), the relative length of digits on one hindlimb (31.2–40.1 versus 22.8–28.2), and the relative distance between the eye and naris (5.01–5.63 versus 4.03–4.98). From P. lanceolatus sp. nov., we distinguish P. oreistes by the relative distance between the eye and naris (5.01–5.63 versus 4.58–4.98). From P. lapierrae sp. nov., we distinguish P. oreistes by the relative length of digits on one hindlimb (31.2–40.1 versus 24.3–30.9), the relative mental width (1.54–1.90 versus 1.92–1.94), the relative longest finger length (5.27–7.23 versus 4.49–4.55), the relative frontal width (61.6–76.9 versus 77.6–79.0), and the relative nasal width (1.37–1.65 versus 1.81). From P. leionotus , we cannot distinguish P. oreistes based on our standard suite of characters (see Remarks). From P. marcanoi , we distinguish P. oreistes by the relative nasal height (0.878–1.06 versus 1.07–1.28). From P. melanchrous , we cannot distinguish P. oreistes based on our standard suite of characters (see Remarks). From P. neiba , we distinguish P. oreistes by the relative nasal width (1.37–1.65 versus 1.67–1.92). From P. nesobous , we distinguish P. oreistes by the relative mental width (1.54–1.90 versus 1.96–2.18), the relative nasal height (0.878–1.06 versus 1.12–1.14), and the relative nasal width (1.37–1.65 versus 1.69–1.71). From P. psychonothes , we distinguish P. oreistes by the relative nasal height (0.878–1.06 versus 1.12–1.32) and the relative nasal width (1.37–1.65 versus 1.68–1.94). From P. saonae , we distinguish P. oreistes by the dorsal pattern (irregular dots/dots in series/ dots in chevrons versus absent), the longitudinal paramedian lines (present versus absent), the relative length of digits on one hindlimb (31.2–40.1 versus 26.5–29.8), the relative mental width (1.54–1.90 versus 1.52), the relative prefrontal width (4.18–4.96 versus 4.14), the relative longest finger length (5.27–7.23 versus 5.01), the relative distance between the eye and naris (5.01–5.63 versus 6.43), and the relative nasal width (1.37–1.65 versus 1.69). From P. semitaeniatus sp. nov., we distinguish Panolopus oreistes by the relative ear width (0.558–1.79 versus 1.90–2.30), the relative head width (66.1–85.0 versus 58.8–63.8), the relative nasal height (0.878–1.06 versus 1.08), the relative angled subocular height (0.737 –0.978 versus 0.654), and the relative distance between the eye and naris (5.01–5.63 versus 4.61). From P. unicolor sp. nov., we distinguish P. oreistes by the dorsal pattern (irregular dots/dots in series/dots in chevrons versus absent), the adult SVL (77.3–103 versus 67.6), the total strigae on ten scales (155–267 versus 144), the relative frontal width (61.6–76.9 versus 58.2), the relative nasal height (0.878–1.06 versus 1.15), and the relative nasal width (1.37–1.65 versus 2.00).

Description of holotype. MCZ R-74940. An adult; SVL 103 mm; tail slightly laterally compressed, broken in life, regenerated, 109 mm (106% SVL); axilla-to-groin distance 57.6 mm (55.9% SVL); forelimb length 23.2 mm (22.5% SVL); hindlimb length 31.7 mm (30.8% SVL); head length 20.0 mm (19.4% SVL); head width 14.3 mm (13.9% SVL); head width 71.5% head length; diameter of orbit 3.17 mm (3.08% SVL); horizontal diameter of ear opening 1.01 mm (0.981% SVL); vertical diameter of ear opening 1.58 mm (1.53% SVL); length of all toes on one foot 32.1 mm (31.2% SVL); shortest distance between angled subocular and lip 0.79 mm (0.767% SVL); shortest distance between the ocular and auricular openings 9.79 mm (9.50% SVL); largest supraocular width 2.83 mm (2.75% SVL); cloacal width 8.00 mm (7.77% SVL); mental width 1.90 mm (1.84% SVL); postmental width 3.29 mm (3.19% SVL); prefrontal width 5.11 mm (4.96% SVL); frontal width 70.4% frontal length; nasal height 1.05 mm (1.02% SVL); angled subocular height 0.86 mm (0.835% SVL); shortest distance between the eye and naris 5.54 mm (5.38% SVL); canthal iii width 1.75 mm (1.70% SVL); angled subocular width 2.44 mm (2.37% SVL); nasal width 1.54 mm (1.50% SVL); rostral 2.22X 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, frontal, and prefrontal fused into a single large plate with a concave posterior margin, much wider than long, bordered by posterior internasals, 1 st loreals, 1 st and 2 nd median oculars, and the frontal; frontal longer than wide; a pair of frontoparietals, fused with frontal, 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 approximately as wide as long; parietal separated from supraoculars by 1 st and 2 nd temporals and frontoparietal (left)/1 st temporal and frontoparietal (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 –5 th supralabial (left)/(right); 2 nd loreal shorter than 1 st, approximately as high as wide (left)/ shorter than 1 st, wider than high (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, and 1 st and 2 nd loreals (left)/1 st median ocular (fused), anterior supraciliary, upper preocular, and 1 st and 2 nd loreals (right); 10 (left)/9 (right) median oculars, 1 st and 2 nd contacting the prefrontal (left)/(right); 1 upper preocular (left)/(right); an irregular anterior supraciliary (left)/ (right); 6 (left)/5 (right) lateral oculars; 5 temporals (left)/(right); 2 suboculars (left)/(right); posterior subocular large and elongate (left)/(right); anterior subocular small (left)/(right); 9 (left)/10 (right) supralabials, 6 (left)/7 (right) to level below center of eye; 9 (left)/10 (right) infralabials, 5 (left)/6 (right) to level below center of eye; mental small, followed by a single, larger postmental; 4 pairs of enlarged chin shields; 1 st pair in contact with one another anteriorly, posteriorly separated by one scale; 2 nd –4 th pairs separated by 1–3 scales; 93 transverse rows of dorsal scales from interoccipital to base of tail; 100 transverse rows of ventral scales from mental to vent; 40 scales around midbody; 5 digits; finger lengths 3>4>2>5>1; 13 (right) lamellae under longest finger; 48 total lamellae on one hand; toe lengths 4>3>2>5>1; 18 (left)/20 (right) lamellae under longest toe; keelless and striate dorsal body and caudal scales; smooth to faintly striated ventral scales; 267 total strigae counted on ten scales.

Color (in alcohol): dorsal surface of head medium brown with several darker brown spots; lateral surfaces of head grading from medium brown to yellow-cream with darker brown eye masks and labial scales; dorsal surfaces of the body are gray-brown with markings in longitudinal paramedian series and faint darker brown spots arranged in vague herring bones farther down the dorsum; dorsal surface of tail same as the body; lateral areas grade from darker brown to dark cream with darker brown and off-white spots arranged in vertical bars; dorsal surfaces of the limbs are medium brown with darker brown mottling; lateral and ventral areas of the limbs grading to dark cream with reduced brown mottling; ventral surfaces of the head, body, and tail are orange-cream with darker spotting under the chest, head, and tail.

Variation. All of the examined material appears similar to the holotype in dorsal pattern and has either dots arranged in chevrons or dots occurring irregularly. Roughly half of the examined material has patternless heads whereas the other half displayed either darker outlines on head scale borders or dark, irregular markings on the head scales. All examined material have markings in the longitudinal paramedian series that range from dots in series, to broken longitudinal paramedian lines, to complete longitudinal paramedian lines. All animals of this species that we examined have dots arranged in bars in the lateral area. Measurements and other morphological data for the holotype and other examined material are presented in Table 1.

Distribution. Panolopus oreistes is distributed in southern Haiti and into the southeastern Dominican Republic at elevations of 0–2220 m (Fig. 49).

Ecology and conservation. No ecological data are associated with this species. We consider the conservation status of Panolopus oreistes to be Least Concern, based on IUCN Redlist criteria ( IUCN 2023). It is likely a common species tolerant of some habitat disturbance, based on what is known of most species of Panolopus . However, it faces a primary threat of habitat destruction resulting from deforestation.A secondary threat is predation from introduced mammals, including the mongoose and black rats. Studies are needed to determine the health and extent of remaining populations and better understand the threats to the survival of the species.

Reproduction. Ovoviviparous, embryos observed in multiple specimens.

Etymology. The species name oreistes is derived from the Greek words oreios, meaning “mountain”, and stes, meaning “dweller.”

Remarks. Previously considered a subspecies of Panolopus costatus , herein we recognize P. oreistes to be a full species based on genetic and morphological differences. Additional specimens categorized as P. costatus from the range of P. oreistes should be examined to determine if they are members of this species.

FIGURE 73. (A–F) Panolopus oreistes (MCZ R-74940, holotype), SVL 103 mm.

FIGURE 74. Panolopus oreistes (ANSP 38608, SBH 269898), in life. From Morne D’Enfer, southwestern edge of plateau, Sud-Est Department, Haiti. Photo by SBH.

Panolopus oreistes and P. costatus cannot be morphologically separated based on our standard suite of characters; however, they can be separated by the area of the nasal scale by the SVL (1.06–1.57 [n=14] versus 1.59–2.03 [n=4]). Panolopus oreistes and P. leionotus cannot be distinguished based on our suite of morphological characters; however, both species are morphologically distinct from their respective closest relative ( P. costatus and P. semitaeniatus sp. nov., respectively). Additionally, P. oreistes and P. leionotus are genetically distinct (Fig. 3) and diverged 3.81 Ma (Fig. 4). Future studies should examine additional characters to morphologically diagnose P. oreistes and P. leionotus . Panolopus oreistes and P. melanchrous cannot be distinguished based on our suite of morphological characters and future studies should examine additional characters to morphologically diagnose those two species.

Panolopus oreistes was 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 P. costatus . Based on our timetree (Fig. 4), P. oreistes diverged from its closest relative 2.43 Ma, consistent with typical species of vertebrates (> 0.7 Ma; Hedges et al. 2015). Panolopus oreistes was recovered as conspecific with Panolopus aporus in our ASAP analysis.