Alinea lanceolata (Cope 1862) Hedges, S. Blair & Conn, Caitlin E., 2012
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publication ID |
https://doi.org/ 10.11646/zootaxa.3288.1.1 |
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persistent identifier |
https://treatment.plazi.org/id/39191A7F-0726-FFCF-2DA9-EEAA7EF4FCEF |
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treatment provided by |
Felipe |
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scientific name |
Alinea lanceolata (Cope 1862) |
| status |
comb. nov. |
Alinea lanceolata (Cope 1862) comb. nov.
Barbados Skink
( Figs. 12B View FIGURE 12 , 13B View FIGURE 13 , 15)
Mabuia lanceolata Cope, 1862:187 . Original syntypes: USNM 6041 View Materials (two specimens, recataloged; new lectotype designation:
USNM 6041 View Materials , formerly 6041A; new paralectotype designation : USNM 572080 View Materials , formerly 6041B), collected by Professor
Theodore Gill on Barbados. Mabuya agilis —Boucourt, 1979:395 (part). Mabuia sloanii — Boulenger, 1887:193 (part). Mabuia agilis — Fielden, 1889:297 (part). Mabuya lanceolata — Barbour, 1914:320. Mabuya mabouia —Barbour, 1930:105 (part). Mabuya mabouia — Barbour, 1935:129 (part). Mabuya mabouya mabouya — Dunn, 1936:544 (part). Mabuya mabouia — Barbour, 1937:147 (part). Mabuya mabouya mabouya — Grant, 1959:101 (part). Mabuya lanceolata — Underwood, 1963:83. Mabuya mabouya mabouya —Peters & Donoso-Barros, 1970:200 (part). Mabuya mabouya mabouya — Schwartz & Thomas, 1975:141 (part). Mabuya mabouya mabouya — MacLean et al., 1977:40 (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 bistriata — Malhotra & Thorpe, 1999:97 (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).
Material examined (n = 3). Barbados. USNM 6041 View Materials (lectotype) , USNM 572080 View Materials (paralectotype), both collected by Theodore Nicholas Gill, no specific locality, 1858 (see Remarks ) ; BMNH 89.7 . 5.13, Colonel H. W. Fielden, Graeme Hall Swamp, ca. 1889 (see Remarks ) .
Diagnosis. Alinea lanceolata is characterized by (1) maximum SVL in males, 82.2 mm; (2) maximum SVL in females, 93.8 mm; (3) snout width, 1.90–2.71% SVL; (4) head length, 16.3–17.8% SVL; (5) head width, 11.2– 12.8% SVL; (6) ear length, 1.23–2.24% SVL; (7) toe-IV length, 9.25–10.8% SVL; (8) prefrontals, two; (9) supraoculars, four; (10) supraciliaries, four (67%), five (33%); (11) frontoparietals, two; (12) supralabial below the eye, five (67%), six (33%); (13) nuchal rows, one; (14) dorsals, 59–61; (15) ventrals, 63–71; (16) dorsals + ventrals, 122–130; (17) midbody scale rows, 30–32; (18) finger-IV lamellae, 13–15; (19) toe-IV lamellae, 15–18; (20) finger-IV + toe-IV lamellae, 28–33; (21) supranasal contact, Y (33%), N (67%); (22) prefrontal contact, N; (23) supraocular-1/frontal contact, Y (33%), N (67%); (24) parietal contact, Y; (25) pale middorsal stripe, N; (26) dark dorsolateral stripe, N; (27) dark lateral stripe, N; (28) pale lateral stripe, N; and (29) palms and soles, pale ( Tables 3–5).
Within the Genus Alinea , A. lanceolata is distinguished from A. berengerae by having more midbody scale rows (30–32 versus 28), a shorter head (head length 16.3–17.8% SVL versus 19.0% in A. berengerae ), shorter toes (toe-IV length 9.25–10.8% SVL versus 12.8%), and a non-attenuate body shape (attenuate in A. berengerae ). It differs from A. luciae by having more dorsals (59–61 versus 54–57) and one row of nuchals (2–3 rows in A. luciae ). From A. pergravis , it differs by having fewer dorsals + ventrals (122–130 versus 132–136 in A. pergravis ), shorter toes (toe-IV 9.25–10.8% SVL versus 11.4–13.2%), and a non-attenuate body shape (attenuate in A. pergravis ).
Description of lectotype (Fig. 15C–D). An adult male in poor state of preservation, without injuries and with an abdominal slit. SVL 82.2 mm; tail length not measured (broken); HL 13.4 mm; HW 9.24 mm; SW 2.17 mm; EL 1.01 mm; and toe-IV length 7.60 mm; ear-opening small in size and oval; toe length in the following order: I <II <V <III <IV.
Head scalation. Rostral wider than high, contacting first supralabials, nasals and supranasals. Paired with frontonasal, both anterior and posterior loreals, first supraciliary, 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 lanceolate, 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 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 loreal rectangular and posterior loreal squarish with posteromedial projection on latter. One or two upper and two lower preoculars. Seven supralabials, the fifth being the widest and forming the lower border of the eyelid. Five moderately enlarged scales behind eye 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. Seven infralabials. Mental scale wider than long, posterior margin straight. Postmental scale and one pair of adjoining chin shields in contact with anterior infralabials. First pair of chin shields in contact medially; second 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, 59 in a longitudinal row; ventrals similar to dorsals; 71 in a longitudinal row; 32 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 17 under toe-IV. Four preanals larger than adjacent ventral scales. No enlarged median subcaudal scales on tail.
Pattern and coloration. Dorsal ground color faded but appears medium brown without visible dark brown spots. Dark dorsolateral stripes, dark lateral stripes, pale middorsal stripe, pale dorsolateral stripes, and pale lateral stripes absent. Ventral surface of body mostly without visible pattern, probably due to poor preservation, but throat (ventral) striping still visible. Palmar and plantar surfaces unpigmented. No information is available on color in life of the lectotype.
Variation. In coloration and scalation, the other material resembled the lectotype ( Tables 4–5), in general. The paralectotype, 65.3 mm SVL (a young adult, unsexed) is also in poor condition, but agrees in scalation with the lectotype (except 30 midbody scale rows, 63 ventrals, 13 finger-IV lamellae, and 15 toe-IV lamellae). As with the lectotype, there is virtually no color pattern visible, almost certainly from the poor state of preservation. Nonetheless, the paralectotype shows some evidence of ventral striping, especially along edges of throat. The third and largest specimen, BMNH 89.7 .5.13 (Fig. 15A–B and E–F), a 93.8 mm SVL female, is in excellent condition and retains details of coloration. It differs somewhat in scalation from the lectotype (30 midbody scale rows, 61 dorsals, 67 ventrals, 15 finger-IV lamellae, and 18 toe-IV lamellae, five supraciliaries, supralabial six below eye, and supranasals in contact). In coloration (Fig. 15E–F) it has a pale gray-green dorsum with many small brown spots on the body and limbs, sometimes in broken lines, and blue-green pale dorsolateral stripes (as noted elsewhere, the blue-green color of many preserved specimens may be an artifact of preservation) .
Distribution. This species is known only from the island of Barbados in the Lesser Antilles ( Fig. 11H View FIGURE 11 ). The only localities known are Greame Hall Swamp and Chancery Lane ( Fielden 1889), about 8 km apart and at the southern tip of the island.
Ecology and conservation. No ecological information is associated with the types. However, the collector of the third specimen writes that it occurs in "damp and rushy situations" ( Fielden 1889). He also notes how the mongoose ( Urva auropunctata ), even by the late 1800s, had already severely impacted the endemic reptiles of the island. Barbados is one of the ten most densely populated countries in the World ( World Resources Institute 2008) and has essentially no original forest remaining ( FAO 2005). Besides the mongoose, black rats ( Rattus rattus Linnaeus ) are on Barbados as well, and are arboreal, and thus the endemic skink would be unable to evade the black rat by climbing trees. Barbour (1937) considered skinks to be extinct on Barbados, as did Underwood (1963), although confirming this would be difficult. Carrington et al. (2003), in their book on Barbados heritage, noted only that the skink species that occurs on Barbados and elsewhere is "often found under rocks or old timber and moves with a snake-like slither" (thus not presenting any evidence of its presence or of new records). The two known localities are both nature preserves, but with no sightings of the species since 1889, there is no evidence that they are preserving that species.
Based on IUCN Redlist criteria ( IUCN 2011), we consider the conservation status of Alinea lanceolata to be Critically Endangered and possibly extinct (CR A2ace). It is known from only three specimens, and there are no records since 1889 despite search efforts by herpetologists, including one of us (S.B.H.). It faces a primary threat 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. The adult female, BMNH 89.7.5.13 (93.8 mm SVL), contained seven fetuses, not fully developed. No specific date of collection is available.
Etymology. The species name ( lanceolata ) is a feminine Latin adjective, meaning spear-like, referring to the acuminate head shape, although this feature is a characteristic of the entire genus Alinea and even more evident in A. pergravis .
Remarks. The collector of the type specimens, Theodore Nicholas Gill (1837–1914), is known to have made only a single expedition to the West Indies (including Barbados), in the first few months of 1858 ( Dall 1916). This constrains the date of collection of those specimens, only 4–5 years before their description by Cope (1862a). The third specimen (BMNH 89.7.5.13) was accessioned in 1889, donated by "Col. Fielding." Almost certainly this refers to Col. H. W. Fielden, who wrote an article on the reptiles of Barbados that same year ( Fielden 1889). In it he mentioned the collection of specimens, referred to as Mabuya agilis , from Graeme Hall Swamp and Chancery Lane. He noted that the local name for it is "scorpion." This provides the only locality information for the species, which has not been recorded since then. More recently, Grant (1959) commented on skinks from Barbados, doubting that they ever occurred on the island. However, we disagree with that opinion and have no doubt that these three specimens came from Barbados, especially given the biographic information on Gill, the account by Fielden, and the specimens that they collected.
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