Mabuya grandisterrae, Hedges & Conn, 2012

Hedges, S. Blair & Conn, Caitlin E., 2012, A new skink fauna from Caribbean islands (Squamata, Mabuyidae, Mabuyinae) 3288, Zootaxa 3288 (1), pp. 1-244 : 101-104

Mabuya grandisterrae sp. nov.

Grande-Terre Skink

( Figs. 30D , 32D , 41 )

Eumeces mabouia — Duméril & Bibron, 1839:646 (part).

Mabouya cepedii — Gray, 1845:95 (part).

Mabuya mabouia — Barbour, 1914:320 (part).

Mabuya sp. indet.—Barbour, 1930:105.

Mabuya mabouia — Barbour, 1935:129 (part).

Mabuya mabouya mabouya — Dunn, 1936:544 (part).

Mabuya mabouia — Barbour, 1937:147 (part).

Mabuya mabouia — Underwood, 1963:83 (part).

Mabuya mabouya mabouya — Schwartz & Henderson, 1991:457 (part).

Mabuya bistriata — Powell et al., 1996:82 (part).

Mabuya bistriata — Malhotra & Thorpe, 1999:84 (part).

Mabuya sloanii — Mayer & Lazell, 2000:883 (part).

Mabuya mabouya — Breuil, 2002:267 (part).

Mabuya mabouya —Miralles, 2005:49 (part).

Mabuya mabouya — Henderson & Powell, 2009:292 (part).

Holotype. BMNH 1920.1 .20.398, an adult female, collected at Pointe-à-Pitre , Grande-Terre, Guadeloupe, by "Vitrac" and donated to the BMNH by F. Lataste; entered into the BMNH registry on 20 January 1920 (and thus collected at some time before that date).

Paratypes (n = 4). Guadeloupe. USNM 11175 , USNM 11249 and USNM 565045–46 , May 1880 , Guadeloupe, no specific locality (no collector information available).

Material not examined (n = 1). Guadeloupe. BMNH 1920.1 .20.399 (paratopotype), same collecting data as holotype .

Diagnosis. Mabuya grandisterrae sp. nov. is characterized by (1) maximum SVL in males, 90.8 mm; (2) maximum SVL in females, 102.1 mm; (3) snout width, 2.34–3.44% SVL; (4) head length, 17.2–19.8% SVL; (5) head width, 12.5–13.9% SVL; (6) ear length, 1.26–2.08% SVL; (7) toe-IV length, 10.2–12.8% SVL; (8) prefrontals, two; (9) supraoculars, two (20%), three (80%); (10) supraciliaries, four; (11) frontoparietals, two; (12) supralabial below the eye, five (80%), six (20%); (13) nuchal rows, one; (14) dorsals, 54–61; (15) ventrals, 62–68; (16) dorsals + ventrals, 116–128; (17) midbody scale rows, 30–34; (18) finger-IV lamellae, 14–15; (19) toe-IV lamellae, 17–18; (20) finger-IV + toe-IV lamellae, 31–33; (21) supranasal contact, Y (80%), N (20%); (22) prefrontal contact, Y (20%), N (80%); (23) supraocular-1/frontal contact, Y; (24) parietal contact, Y; (25) pale middorsal stripe, N; (26) dark dorsolateral stripe, N; (27) dark lateral stripe, Y; (28) pale lateral stripe, N; and (29) palms and soles, dark ( Tables 3–5).

Within the Genus Mabuya , M. grandisterrae sp. nov. and the other three species inhabiting Guadeloupe and its islets ( M. cochonae sp. nov., M. desiradae sp. nov., and M. guadeloupae sp. nov.), here placed in the M. guadeloupae sp. nov. species group, have a similarly-proportioned frontonasal scale that distinguishes them from other species in the genus ( Fig. 34 ). Species in the M. guadeloupae sp. nov. species group have a longer frontonasal compared with M. montserratae sp. nov. (frontonasal length/head length 0.176 –0.199 versus 0.165 – 0.168) and a shorter frontonasal compared with other species in the genus (0.176 –0.199 versus 0.205 –0.239 in M. dominicana , M. hispaniolae sp. nov., and M. mabouya ). In addition, M. grandisterrae sp. nov. differs from M. dominicana by lacking pale dorsolateral stripes and a well-defined pale lateral stripe (such stripes are present in M. dominicana ). It is separated from M. hispaniolae sp. nov. by lacking well-defined pale lateral stripes (present in M. hispaniolae sp. nov.).

Mabuya grandisterrae sp. nov. differs from M. cochonae sp. nov., M. desiradae sp. nov., and M. guadeloupae sp. nov. by having a lower supraciliary-2/supraciliary-3 length ratio (1.67–1.79 versus 2.06–2.40; Fig. 36 ). It differs from M. cochonae sp. nov. in having fewer ventrals (62–68 versus 70), a shorter anterior loreal scale (1.35– 1.74% SVL versus 2.26–2.47% SVL; Fig. 37A ), a shorter suture length between the upper secondary temporal and the parietal scale (1.59–1.93 versus 2.12–2.29% SVL; Fig. 37C ), and a larger ear (1.26–2.08 versus 1.02–1.12% SVL). Mabuya grandisterrae sp. nov. differs from M. desiradae sp. nov. in having fewer dorsals (54–61 versus 62), fewer dorsals + ventrals (116–128 versus 130–132), and a shorter dark lateral stripe that extends one-third (versus two-thirds) of body. Mabuya grandisterrae sp. nov. differs from M. guadeloupae sp. nov. in having a wider head (12.5–13.9% SVL versus 11.6–12.0% SVL), a longer toe (toe-IV 10.2–12.8% SVL versus 8.77–9.72% SVL), a longer interloreal suture (0.90–1.16% SVL versus 0.64–0.85% SVL; Fig. 37B ), a longer supralabial-7 (1.62– 2.00% SVL versus 1.36–1.44% SVL; Fig. 37D ), and absence of dark dorsolateral stripes and well-defined pale lateral and dorsolateral stripes (those stripes present and well-defined in M. guadeloupae sp. nov.).

Description of holotype ( Figs. 30D , 41 ). An adult female in good state of preservation, although the irregular and asymmetrical head scalation suggests that it sustained a head injury at some point in its life. An abdominal slit is present. SVL 84.3 mm; tail complete (length not measured); HL 15.3 mm; HW 11.7 mm; SW 2.67 mm; EL and toe-IV length not measured; ear-opening moderate in size, round; toe length in the following order: I <V <II <III

Head scalation. Rostral wider than high, contacting first supralabials, nasals and supranasals. Paired supranasals in median contact, contacting anteriormost loreal (right side only). Frontonasal diamond-shaped, wider than long, laterally in contact with anterior loreal scale. A pair of quadrilateral prefrontals, in contact medially, and in contact with frontonasal, both anterior and posterior loreals, first supraciliary, first supraoculars, and frontal. Frontal small and asymmetrical (roughly triangular), in contact with the first supraoculars. Frontoparietals also in contact with parietals and interparietal. Interparietal tetragonal and lanceolate, separated from nuchals by parietals; parietal eye distinct. Parietals in contact with upper secondary and tertiary temporal scales. Three supraoculars, the first one being the longest and largest. Four supraciliaries, the second the longest. Nostril in posterior part of the nasal. A small postnasal, bordered by supranasal, anterior loreal and first supralabial. Anterior and posterior loreals squarish with posterodorsal projection on latter. Two upper preoculars and two lower preoculars. Eight supralabials on the right and seven on the left, the sixth on the right and the fifth on the left being the widest and forming the lower border of the eyelid. Four moderately enlarged scales behind eye (five on the left) comprising the postoculars; similar to temporal scales but smaller. One primary temporal, two secondary temporals, and three tertiary temporals; all imbricate, smooth, cycloid, not distinctly delimited from the scales on the nape and the sides of the neck. Eight infralabials (seven on the left). Mental scale wider than long, posterior margin curved slightly toward tip of snout. Postmental scale and two pairs of adjoining chin shields (plus one additional right chin shield) in contact with anterior infralabials. First two pairs of chin shields in contact medially; third pair separated by a smaller cycloid scale.

Body and limb scalation. One row of paired nuchal scales. Other scales on nape similar to dorsals. On lateral sides of neck, scales slightly smaller. Dorsal scales cycloid, imbricate, smooth, 56 in a longitudinal row; ventrals similar to dorsals; 64 in a longitudinal row; 34 scales around midbody. No distinct boundaries between dorsals, laterals and ventrals. Scales on tail and limbs similar to dorsals, except smaller on limbs. Palmar and plantar regions with small tubercles, subequal in size and delimited by a surrounding region of flatter scales. Subdigital lamellae smooth, single, 15 under finger-IV and 18 under toe-IV. Preanal scales similar to ventrals. Median subcaudal scales gradually increasing in size from base to tip of tail. stripes absent. Dark lateral stripes present, dark brown with pale bluish-gray spots posterior to hindlimbs, extending from loreal region to first third of body. Pale middorsal stripe, pale dorsolateral stripe, and pale lateral stripe absent. Ventral surface of body without pattern. Palmar and plantar surfaces dark brown. No information on color in life is available for the holotype, although its pale bluish-green hue suggests that it was tan.

Variation. In coloration and scalation, the paratypes resembled the holotype, although the pattern was much faded in the four USNM specimens, which appeared uniformly brown, apparently from formalin fixation ( Tables 4–5). The pattern of the holotype is in much better condition; the bluish-green hue is probably a reaction to preservative .

Distribution. The species is distributed on Guadeloupe (1,628 km 2), where the only known locality is the city of Pointe-à-Pitre, Grande-Terre ( Fig. 11B ). No specific locality data are associated with the USNM paratypic specimens.

Ecology and conservation. No ecological information exists for this species. It has not been observed in about a century, likely because of predation by the introduced mongoose or other mammalian predators. However, Guadeloupe is a large island, and there are small, fringing islets that might provide a mongoose-free haven for this species.

Based on IUCN Redlist criteria ( IUCN 2011), we consider the conservation status of Mabuya grandisterrae sp. nov. to be Critically Endangered and possibly extinct (CR A2ace). It faces a primary threat from the introduced mongoose, which has probably led to its extinction. Secondary threats include habitat destruction from agriculture and urbanization, and predation from other introduced predators, including black rats. Studies are needed to determine if the species still exists, the health of any remaining populations, and threats to the survival of the species. Captive breeding programs should be undertaken, if the species still exists, because eradication of introduced mammalian predators is not possible on large islands.

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

Etymology. The species name ( grandisterrae ) is a feminine genitive singular noun, referring to the distribution of the species on Grand-Terre, Guadeloupe.

Remarks. Of the nine known specimens of Mabuya from the main islands of Guadeloupe (Grande-Terre and Basse-Terre), only the holotype and associated paratype (BMNH 1920.1.20.398–388) of this species, M. grandisterrae sp. nov., have a specific locality. The three FMNH specimens are quite clearly a different species, described below ( M. guadeloupae sp. nov.). It is possible that both species were broadly sympatric on both islands. However, given that they are similar in body size, and therefore would have competed with one another, we think it is more likely that M. grandisterrae sp. nov. evolved on the drier island, Grande-Terre (because two specimens are from that island), and the other species ( M. guadeloupae sp. nov.) evolved on the wetter island, Basse-Terre. The coloration of the two species could be viewed as supporting that assumption: M. guadeloupae sp. nov. appears to be a darker species than M. grandisterrae sp. nov., a coloration trend often seen in reptiles, where areas with higher rainfall often have more darkly-colored species.

Figures

FIGURE 11. Map showing the distribution of mabuyine skinks occurring in the Lesser Antilles and Trinidad and Tobago. See Fig. 1 for location of the islands. The islands and species are: (A) Anguilla, Dog Island, and St. Barts (Spondylurus powelli sp. nov., squares), and St. Martin (S. martinae sp. nov., circle); (B) Guadeloupe: Basse-Terre (Mabuya guadeloupae sp. nov., square), Grande-Terre (Mabuya grandisterrae sp. nov., triangle), Îlet à Cochons (Mabuya cochonae sp. nov., star), La Désirade and Terre de Bas, Petite-Terre (Mabuya desiradae sp. nov., diamonds), and Marie-Galante (Capitellum mariagalantae sp. nov., circle); (C) Martinique (Mabuya mabouya, circles; Capitellum metallicum, triangle); (D) St. Vincent, the Grenadines, and Grenada (Copeoglossum aurae sp. nov., circles; Marisora aurulae sp. nov., triangles); (E) Redonda (Copeoglossum redondae sp. nov., circle) and Montserrat (Mabuya montserratae sp. nov., square); (F) Dominica (Mabuya dominicana); (G) St. Lucia (Alinea luciae), (H) Barbados (Alinea lanceolata); (I) Trinidad (Copeoglossum aurae sp. nov., circles; Marisora aurulae sp. nov., triangle), and (J) Tobago (Copeoglossum aurae sp. nov., circles; Marisora aurulae sp. nov., triangles). Hollow symbols in A and J are literature records (specimens not examined). Where no specific localities within an island are known for a species, a symbol is placed centrally on the island: Alinea luciae, Capitellum mariagalantae, Capitellum metallicum, and Copeoglossum redondae sp. nov. The scale in (A) applies to all islands.

FIGURE 30. Head scalation in species of the Genus Mabuya (left, side view; right, dorsal view). (A) M. cochonae sp. nov. (KU 242043, holotype); (B) M. desiradae sp. nov. (KU 242045, holotype); (C) M. dominicana (MCZ R-182281); and (D) M.

FIGURE 32. Representative patterns in species of the Genus Mabuya (top, dorsal view; bottom, side view). (A) M. cochonae sp. nov.; (B) M. desiradae sp. nov.; (C) M. dominicana; (D) M. grandisterrae sp. nov.; (E) M. guadeloupae sp. nov.; (F) M. hispaniolae sp. nov.; (G) M. mabouya; and (H) M. montserratae sp. nov.

FIGURE 34. Graph of frontonasal length versus head length in the eight species of the Genus Mabuya.

FIGURE 36. Graph of supraciliary-2 length versus supraciliary-3 length in the eight species of the Genus Mabuya.

FIGURE 37. Graphs of four diagnostic characters of head scalation in the Mabuya guadeloupae sp. nov. species group (M.

FIGURE 41. Mabuya grandisterrae sp. nov., from Guadeloupe. (A–D) BMNH 1920.1.20.398, holotype, Pointe-à-Pitre, Basse-Terre.