A new species of Dibamus Duméril & Bibron, 1839 (Squamata: Dibamidae) from Pulau Manado Tua, Northern Sulawesi, Indonesia

Abstract

Based on three adult specimens, viz. two males and a female that form the type series, a new species of blind or worm-like lizards is described from Pulau (= Island) Manado Tua, a little volcanic island located off the northern tip of the Minahassa Peninsula of Sulawesi, Indonesia. Dibamus manadotuaensis sp. nov. differs from all congeneric species in the following unique combination of characters: maximum snout-vent length 135 mm; tail length up to 14.2 mm (i.e., 12–13% of SVL); labial and nasal sutures present and complete; four (three) postoculars; four to six scales on posterior edge of infralabial; 26–28 midbody scale rows; 30–33 transverse scale rows posterior to head; 25 transverse scale rows anterior to vent; 218–232 ventral scales; 39 subcaudal scales; relative size of frontal to frontonasal 0.68–0.73; relative size of interparietal to surrounding scales 0.67–1.43; 132–135 presacral and 21–24 postsacral vertebrae. Morphologically, D. manadotuaensis is most similar to D. celebensis, which occurs on mainland Sulawesi.Dibamus manadotuaensis sp. nov. represents the twenty-fourth species of Dibamus and the third species of this genus recorded from the Sulawesi region. At the same time, it is the only squamate species considered endemic for the islands of the Bunaken Marine National Park, to which Manado Tua belongs.

Structural and environmental constraints on reduction of paired appendages among vertebrates

“…Squamate reptiles and lissamphibians were scored as lacking their limbs (1) if both pairs of appendages were absent, and as intermediate (01) if only one pair of appendages has been lost. The only exceptions to this rule are snakes with underdeveloped hindlimbs (e.g., pythons, Pachyrhachis, Haasiophis), the genus Dibamus in which the presence of hindlimbs are a sexual dimorphic character (vestigial hindlimbs only present in males; Koppetsch et al, 2019), and Amphiuma, which have been scored as limbless although they possess small vestigial hindlimbs useless for locomotion. Lifestyle has been divided in "fossorial" or "not fossorial".…”

The palatal gland of dibamid lizards

“…The family Dibamidae is a group of fossorial, limbless, almost eyeless lizards (Koppetsch et al, 2019), with 25 living species, distributed throughout Southeast Asia ( Dibamus : 24 species) and Eastern Mexico ( Anelytropsis papillosus ), with one fossil, Hoeckosaurus mongoliensis , represented by jaw fragments from the Oligocene of Mongolia (Čerňanský, 2019).…”

The atlas–axis complex in Dibamidae (Reptilia: Squamata) and their potential relatives: The effect of a fossorial lifestyle on the morphology of this skeletal bridge

“…Members of the genus Dibamus occur in scattered locations across tropical Southeast Asia (Vietnam, Cambodia, Thailand, Peninsular Malaysia, Borneo, Indonesia), and are also found as far west as the Nicobar Islands of India and east to the Philippines and New Guinea. By contrast, Anelytropsis is distributed in a relatively small area of northeastern Mexico (e.g., Darevsky, ; Das & Lim, , , ; Das & Yaakob, ; Greer, ; Koppetsch, Böhme, & Koch, ; Neang et al, ; Quah, Shahrul, Grismer, & Grassby‐Lewis, ). All dibamid species are small to medium sized ( Dibamus snout‐vent‐length: 52–203 mm; Anelytropsis papillosus : 77–180 mm) and have a small skull (5–7 mm; see Greer, ; Evans, ).…”