Copeoglossum redondae, 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 : 82-85

Copeoglossum redondae sp. nov.

Redonda Skink

( Figs. 23C , 24C , 29 )

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

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

Mabuya mabouya mabouya —Peters & Donoso-Barros, 1970:200 (part).

Mabuya mabouya mabouya — Schwartz & Thomas, 1975:141 (part).

Mabuya mabouya mabouya — MacLean et al., 1977:38 (part).

Mabuya mabouya mabouya — Schwartz & Henderson, 1988:150 (part).

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

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

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

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

Mabuya sloanii — Henderson & Powell, 2009:293.

Holotype. ANSP 9517 , an adult female, collected on Redonda in 1863–1873 (see Remarks), and donated to the Academy of Natural Sciences of Philadelphia by Dr. Hendrik van Rijgersma.

Diagnosis. Copeoglossum redondae sp. nov. is characterized by (1) maximum SVL in males, not available; (2) maximum SVL in females, 100.1 mm (only specimen); (3) snout width, 2.89% SVL; (4) head length, 16.1% SVL; (5) head width, 14.1% SVL; (6) ear length, 2.42% SVL; (7) toe-IV length, 9.43% SVL; (8) prefrontals, two; (9) supraoculars, four; (10) supraciliaries, five (50%), six (50%); (11) frontoparietals, two; (12) supralabial below the eye, five (50%), six (50%); (13) nuchal rows, one; (14) dorsals, 53; (15) ventrals, 59; (16) dorsals + ventrals, 112; (17) midbody scale rows, 30; (18) finger-IV lamellae, 14; (19) toe-IV lamellae, 15; (20) finger-IV + toe-IV lamellae, 29; (21) supranasal contact, N; (22) prefrontal contact, N; (23) supraocular-1/frontal contact, N; (24) parietal contact, N; (25) pale middorsal stripe, N; (26) dark dorsolateral stripe, Y; (27) dark lateral stripe, Y; (28) pale lateral stripe, Y; and (29) palms and soles, dark (possibly darkened by preservative) ( Tables 3–5).

Within the Genus Copeoglossum , C. redondae sp. nov. differs from all other species except C. nigropunctatum by having a larger auricular opening (ear length 2.42% SVL versus 1.02–2.19% in those other species). It differs from C. nigropunctatum by having a narrower frontonasal scale (frontonasal width/length 1.20 versus 1.30–2.03 in C. nigropunctatum ) ( Fig. 26 ), a shorter supraocular-2 scale (supraocular-2/supraocular-1 length ratio 0.58 in C. redondae sp. nov. versus 0.68–1.23 in C. nigropunctatum ; Fig. 27 ), and supranasals not in contact (in contact in 94% of C. nigropunctatum ). Copeoglossum redondae sp. nov. differs from C. arajara ( Rebouças-Spieker 1981) in having more finger-IV + toe-IV lamellae (29 versus 26) and more supraciliaries (5–6 versus four, or rarely three or five, in C. arajara ). Copeoglossum redondae sp. nov. differs from C. aurae sp. nov. in having broad contact between the first paired chin shields and infralabials (no contact in C. aurae sp. nov.) and a shorter toe-IV (9.43% SVL versus 10.1–12.7%). Copeoglossum redondae sp. nov. differs from C. margaritae sp. nov. in having a lower number of ventral scales (59 versus 66), a shorter supraocular-2 scale (supraocular-2/supraocular-1 length ratio diagnostic traits of that genus (see above), especially the separation of the parietal scales and low dorsal + ventral scale count. It also has dark dorsal spots (no dorsolateral stripes) and dark lateral stripes extending onto tail, both characteristics of the genus.

Description of holotype ( Figs. 23C , 29 ). An adult female in good state of preservation, without injuries and with an abdominal slit. SVL 100.1 mm; tail length 145.5 mm (complete, never regenerated, but in two separate pieces); HL 16.1 mm; HW 14.1 mm; SW 2.89 mm; EL 2.42 mm; and toe-IV length 9.44 mm; ear-opening large in size and round; toe length in the following order: I <V <II <III <IV.

Head scalation. Rostral wider than high, contacting first supralabials, nasals and supranasals. Paired supranasals not in median contact, contacting anteriormost loreal. Frontonasal diamond-shaped, wider than long, laterally in contact with anterior loreal scale. A pair of quadrilateral prefrontals, separated medially, and in contact with frontonasal, both anterior and posterior loreals, first supraoculars, and frontal. Frontal heptagonal, in contact with the second supraoculars and paired frontoparietals. Frontoparietals also in contact with parietals and interparietal. Interparietal tetragonal and acorn-shaped, not separated from nuchals by parietals; parietal eye distinct. Parietals in contact with upper secondary and tertiary temporal scales. Four supraoculars, the second one being the largest. Six (left) and five (right) 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 posteromedial projection on latter. Two upper preoculars and two lower preoculars. Seven (right) and eight (left) supralabials, the fifth (right) and sixth (left) being the widest and forming the lower border of the eyelid. Two moderately enlarged scales behind eye comprising the postoculars on the right and three on the left; 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. Mental scale wider than long, posterior margin straight. Postmental scale and one pair of adjoining chin shields (plus one additional left 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, 53 in a longitudinal row; ventrals similar to dorsals; 59 in a longitudinal row; 30 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, 14 under finger-IV and 15 under toe-IV. Four preanals larger than adjacent ventral scales. Enlarged median subcaudal scales on tail.

Pattern and coloration. The pattern is present but considerably faded from many years in preservative. Dorsal ground color pale brown with medium brown spots, distributed on body and limbs (limbs are more densely spotted and mottled). Dark dorsolateral stripes absent. Dark lateral stripes present, medium brown, extending from loreal region to last third of body and onto tail. Pale middorsal stripe absent. Pale dorsolateral stripes absent. Pale lateral stripes present, pale tan, extending from behind eye to hindlimbs, bordered below by a narrow dark line. Ventral surface of body without pattern. Palmar and plantar surfaces pale brown to medium brown, similar to ground color. No information is available on color in life of the holotype.

Variation. No other specimens are known. Measurements and other morphological data for the holotype are presented in Tables 3–5.

Distribution. The species is distributed on Redonda ( Fig. 11E ), only ~ 2 km 2.

Ecology and conservation. No ecological information is available. Guano mining took place on Redonda from 1869 to about 1920, during which time the island was inhabited. Since then it has been uninhabited, but there are feral goats ( Capra aegagrus Erxleben ) and black rats ( Rattus rattus ) ( Daltry 2007), which have almost certainly disturbed the habitat. No individuals have been seen since the holotype was collected.

Based on IUCN Redlist criteria ( IUCN 2011), we assess the conservation status of Copeoglossum redondae sp. nov. to be Critically Endangered and possibly extinct (CR A2ace). It faces a primary threat from predation by introduced mammals, 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.

Etymology. The species name ( redondae ) is a feminine genitive singular noun and refers to the distribution of the species on the island of Redonda.

animals and sent the latter to the Academy of Natural Sciences, Philadelphia. They were received by Edward Drinker Cope, who acknowledged the collection ( Holthius 1959). No information is associated with this specimen other than the island and the donor, but we note that the date of collection can be constrained by a notice published in 1873 ( Leidy 1873) stating that a "jar containing a collection of small vertebrates and some invertebrates, from the Isle Redowda, W.I., was presented by Dr. R. E. Van Rijgersma." Despite the misspellings, this certainly refers to H. E. van Rijgersma and Redonda Island. Dunn mentioned this specimen in the first sentence of his revision of "American Mabuyas" ( Dunn 1936): "the following notes are an attempt to name Mabuyas from the islands of St. Martin, Redonda, and Marie Galante, in the collection of the Academy."

Miralles (2005) considered " M. mabouya " to be "the most southern species in the Lesser Antilles" and "endemic to Dominica, Guadeloupe, Martinique and St. Lucia," but he did not mention or discuss the skinks from northern islands ( St. Martin, Redonda or Montserrat) or those south of St. Lucia ( St. Vincent, Grenadines, and Grenada).

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 23. Head scalation in species of the Genus Copeoglossum occupying Caribbean islands (left, side view; right, dorsal view). (A) C. aurae sp. nov. (BMNH 90.11.25.16, paratype); (B) C. margaritae sp. nov. (USNM 217141, holotype); and (C) C. redondae sp. nov. (ANSP 9517, holotype).

FIGURE 24. Representative patterns in species of the Genus Copeoglossum occupying Caribbean islands (top, dorsal view; bottom, side view). (A) C. aurae sp. nov.; (B) C. margaritae sp. nov.; and (C) C. redondae sp. nov.

FIGURE 26. Graph of frontonasal width versus frontonasal length in the five species of the Genus Copeoglossum. The syntypes of Tiliqua aenea Gray (= Copeoglossum nigropunctatum) are indicated with arrows.

FIGURE 27. Graph of suture length between supraocular-2 and supraciliaries versus that between supraocular-1 and supraciliaries in four species of the Genus Copeoglossum. Copeoglossum arajara is not included because it has three supraoculars, possibly from fusion between first and second supraoculars.

FIGURE 29. Copeoglossum redondae sp. nov., from Redonda. (A–D) ANSP 9517, holotype, Redonda (no specific locality).