Two New Species of Toxicocalamus (Squamata: Elapidae) from Papua New Guinea
I describe two new species of the fossorial elapid snake genus Toxicocalamus from New Guinea. The first is restricted to the D'Entrecasteaux Islands off the southeastern tip of New Guinea; the second is known from only a single locality along the southern versant of the Central Highlands. The first species is a member of the Toxicocalamus loriae group, whose members are poorly differentiated from each other by scalational features but can be distinguished by differences in size, color pattern, and morphometric variables; it represents one of six clades of T. “loriae” previously identified using genetic data. Remaining populations assigned to T. loriae require further collecting and research to clarify their taxonomic relationships. The second species is more morphologically distinct and is most similar to Toxicocalamus stanleyanus. It is known from a single specimen, but it occurs in a region with few obvious topographic barriers, leaving uncertain the extent to which it may range more broadly across the southern foothills of the Central Highlands.Abstract
Portraits in life of (A) Toxicocalamus nigrescens (holotype, BPBM 16545), (B) Toxicocalamus loriae from northwest side of Mt Obree, Central Province (BPBM 19503), and (C) Toxicocalamus cratermontanus (holotype, USNM 562941).
(A) Lateral and (B) dorsal view of head of holotype (BPBM 16545) of Toxicocalamus nigrescens; (C) lateral and (D) dorsal view of head of holotype (USNM 562941) of Toxicocalamus cratermontanus. Scale bar = 5 mm.
Map of Papua New Guinea showing type locality for Toxicocalamus nigrescens (solid circle) on Oya Waka, Fergusson Island, Milne Bay Province; additional locality for T. nigrescens at Basima, Fergusson Island, Milne Bay Province (open circle); type locality for Toxicocalamus loriae on Mt. Victoria, Central Province (solid square); locality for my comparative sample of T. loriae from Mt. Obree, Central Province (open square); and type locality for Toxicocalamus cratermontanus (star) on Crater Mountain, Chimbu Province, Papua New Guinea. Type localities are shown for taxa currently synonymized with T. loriae: Apistocalamus lamingtoni on Mt. Lamington, Oro Province (filled hexagon), Apistocalamus pratti at Dinawa, Central Province (open hexagon), and Pseudapistocalamus nymani at Sattelberg, Morobe Province (triangle); type locality for Apisthocalamus loennbergii is off the map at Fakfak, West Papua Province, Indonesia, 1,700 km west of the Papuan Peninsula. Numbers refer to “T. loriae” clades sampled by Strickland et al. (2016).
Bivariate plots of head features showing relatively longer snout and smaller eye of Toxicocalamus nigrescens (circles) versus that of Toxicocalamus loriae (squares). (A) Relative snout length as measured by distance between eye and naris vs. distance between external nares; and (B) relative eye width as measured against head length.
