Tuesday, November 13, 2012

[Herpetology • 2004] Systematics of the Carliafusca” lizards (Squamata: Scincidae) of New Guinea and Nearby Islands

Carlia aenigma Zug, 2004 | Carlia ailanpalai Zug, 2004 | Carlia aramia Zug, 2004
Carlia eothen Zug, 2004 | Carlia mysi Zug, 2004 | Carlia tutela Zug, 2004

On New Guinea and its surrounding islands, an assortment of Carlia with weakly tricarinate to smooth dorsal scales has been variously recognized as C. fusca or members of the fusca group. The C. fusca group has never been defined or characterized explicitly, nor has any other group of Carlia. A preliminary cladistic analysis of the Australian, New Guinean, and Sundan Carlia failed to identify species groups. This maximum parsimony analysis using a character set of predominantly scalation and body proportions yielded 1 putative clades with the other Carlia species branching before this clade. Additionally, the 2 Lygisaurus species are within the Carlia cluster and near the base. Removing body size and sexual dimorphism yielded a consensus tree with 2 small clades among a massive polytomy of all other taxa including the outgroups; the clades were: (dogare,  vivax); (((coensis, scirtetis) beccarii, luctuosa) longipes, rostralis). The New Guinea “fusca” species were not linked as an unambiguous clade; nevertheless, the subsequent morphological analyses demonstrated a high similarity of the New Guinea species and their continued recognition as the Carlia fusca complex is recommended. This complex contains only the New Guinea and adjacent island species, C. leucotaenia and C. tutela of the Mollucas, C. longipes of Cape York and Torres Strait islands, and tentatively the Lesser Sundan species C. babarensis and C. beccarii. This complex is characterized, but it is not proposed as a formal taxonomic unit.

Quantitative analysis of meristic, morphometric, and color pattern characters of New Guinean C. ”fusca” reveals at least 14 species in the New Guinea region. Names are available for the Babar and Tanimbar populations (C. babarensis); the Kei islands (C. beccarii); southeastern Irian Jaya (IJ) and Aru (C. diguliensis); Waigeo, north coastal Vogelkop IJ (C. fusca); southeastern Papua New Guinea (PNG) (C. luctuosa); northeastern IJ and northwestern PNG (C. pulla); and Seram-Ambon (C. leucotaenia). Although interpopulational variation in scalation is slight, differences in juvenile and adult coloration and adult sizes suggest the recognition of the previous named species as well as several new species. The new species are C. aenigma from the eastern PNG Gulf lowlands, C. ailanpalai from the Admiralty Islands, C. aramia from the central PNG Gulf area to the Morehead plains and to mid elevations in the Fly drainage, C. eothen from the vicinity of Milne Bay and the eastern island groups, C. mysi of the PNG north coast from Adelbert Mtns. area east to Cape Vogel and the Bismarck Archipelago, and C. tutela of Halmahera and Morotai. Several areas (PNG highlands, IJ south-central coast, and Sepik drainage) have populations that potentially represent new species, but the present samples and analyses were inadequate for confirmation.

Current morphological data provide no reliable clues to assess interspecific relationships among the New Guinea “fusca” complex, hence this uncertainty does not allow a detailed biogeographical analysis. The distributions of the presently recognized taxa do not match closely those of any other clade of lizards, or any other group of reptiles, amphibians, or other New Guinea organisms. The oldest portion of New Guinea, the Australian craton, harbors the greatest number of fusca complex species but offers no direct clues to their isolation and subsequent speciation. 

Unicolor populations occur in several areas, typically small island habitats. The Admiralty populations are recognized as a distinct species, C. ailanpalai, and the similarity of the Guam Carlia suggests that this population and those on nearby Micronesian islands derive from the Admiralties and the post-World War II transport of military supplies. The Kei, north coast IJ, and Halmahera unicolor populations cannot be assigned with surety to any of the recognized species. The Palau Carlia also appears to represent an accidental post-WWII introduction. Morphological evidence and to a lesser extent color pattern suggest that it derives from C. tutela populations of Halmahera and Morotai.

Zug,G. R. 2004. Systematics of the Carlia fusca” lizards (Squamata: Scincidae) of New Guinea and Nearby Islands. Bishop Mus. Bull. Zool. 5: 1-83