202 the Identity of the Santorini Skink, Chalcides Moseri Ahl, 1937

202 The identity of the Santorini skink, Chalcides moseri Ahl, 1937 (Squamata, Scincidae) Vincenzo Caputo1, Benedetto Lanza2 'Dipartimento di BiologiaEvolutiva e Comparata, Universita' degli Studi di Napoli FedericoII, via Mez- zocannone8, 80134 Napoli, Italy. 2Dipartimentodi Biologiaanimale e Geneticae Museo Zoologico'La Specola'(sezione del Museodi Storia Naturale), Universita' degli Studi di Firenze, via Romana 17, 50125 Firenze, Italy. In 1937 the German herpetologist E.Ahl described a new species of scincid lizard, Chalcides moseri, collected some years earlier on the Santorini Island (Cyclades, Aegean Sea). He held that the new species was closely related to Chalcides spheno,bsiformis[now Sphenops sphenopsiforml*s(Duméril, 1856), according to Pasteur & Bons, 1960] which inhabits southern Morocco, Senegal and Mauritania (Welch, 1982). It would be dif- ferent from the latter species only in the presence of a small postnasal touching the '1st and 2nd supralabials and in its longer forelimbs. In his short survey of the biogeographical origin of Chalcides moseri, Ahl did not rule out that it might have been carried to the Aegean island by human agency, and came to the conclusion that the question would be cleared up only by collecting more specimens. Subsequent investigations did not provide useful information; thus Wettstein (1939, 1953) suggested that the occurrence of this lizard on an Aegean island was debatable even because lizards from the Balearic Islands were present in the same collection. More recently, in a study on the herpetofauna of the Santorini Archipelago, Fr6r and Beutler (1978) have questioned the actual origin of that specimen. In addition, they state that "the existence of this animal as a species of its own seems to be very doubt- ful" (see also Chondropoulos, 1986; Ondrias, 1968). Werner (1938) had already raised doubts on the validity of Chalcides moseri, considering it as a probably mislabelled specimen of Chalcides mionecton (Boettger, 1873). According to Wettstein (1939, 1953), however, Chalcides moseri would be a good species, closely related to Chalcides sphenopsiformis. It would differ from the latter only in having a larger and blunted snout, and longer and more slender hindlimbs. In order to elucidate this old taxonomic enigma we re-examined the type of Chalcides moseri (ZMB 35587): the specimen appears badly preserved (fig. 1), being dried with markedly sunken ocular and periocular regions. We also studied some specimens of Sphenops boulengeri(Anderson, 1892), S. sepsoides (Audouin, 1827), and S. sphenopsiformi's (Duméril, 1856) (table 1), i.e. all the species of the genus Sphenops Wagler, 1830, except S. delislei (Lataste, 1880). As regards this last species, we referred to the data published by Pasteur and Bons (1960). The whole of the features examined fall within the variability range of the Sphenops species so far known (Pasteur and Bons, 1960). In particular, characters 4, 5, 6 [as already pointed out by Wettstein (1939), Ahl's (1932) report on the occurrence of a 203 Figure 1. Type of Chalcidesmoseri. postnasal is erroneous], 14, 16 and 17 are exclusively present in Sphenops sphenopsiformi's (table 1; fig. 2). Other features that C. moseri shares with this species are: the shape of the frenocular scale, which is as long as it is high, and the proportions of the forelimbs which are shorter than the distance between the snout apex and the anterior border of the eye. The longer and more slender hindlimbs of the specimen (fig. 3), showing also longer fingers, can be explained by considering that the squamates involved in processes of limb reduction, like the genus Sphenops, may show remarkable morphological unsteadiness in their appendicular skeleton (see Essex, 1927; Greer and Cogger, 1985; Raynaud et al., 1989). In the light of what reported above, we consider Chalcides moseri Ahl, 1937, a synonym of Sphenops sphenopsiformis (Duméril, 1856). Eventually, as far as the geographical origin of "Chalcides moseri" is concerned, Wettstein's (1939) observation about the presence of lizards from the Balearic Islands in the same collection would suggest a mislabelling; this also considering that similar mishaps have occurred even in recent times (e.g. Chalcides atlantis Pasteur, 1962, which afterwards Pasteur himself (1981) realized to be a mislabelled specimen of Chalcides mionecton). However, as the collecting data of "C. moseri" are extremely careful, it can- not be ruled out that, as suggested by Ahl, the animal reached the Santorini Island .

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