Sigalegalephrynus, Smart & Sarker & Arifin & Harvey & Sidik & Hamidy & Kurniawan & Smith, 2017

Smart, Utpal, Sarker, Goutam C., Arifin, Umilaela, Harvey, Michael B., Sidik, Irvan, Hamidy, Amir, Kurniawan, Nia & Smith, Eric N., 2017, A New Genus and Two New Species of Arboreal Toads from the Highlands of Sumatra with a Phylogeny of Sundaland Toad Genera, Herpetologica 73 (1), pp. 63-75 : 63-75

Sigalegalephrynus gen. nov.

Type species. — Sigalegalephrŋnus mandailinguensis by present designation.

Diagnosis and comparisons. —The genus can be diagnosed based on the following ecological attributes and morphology: medium-sized (<40 mm SVL) member of Bufonidae , with gangly limbs, and arboreal and troglodytic habits. The morphologically comparable genus Ansonia (> 40 mm SVL), commonly called Stream toads, is typically found on low vegetation near watercourses. The generally diminutive members of Pelophrŋne (<40 mm SVL) and Leptophrŋne (> 40 mm SVL) occur on shrubs. The only other genus of toads that has true arboreal habits is Rentapia , whose members typically tend to be stockier (> 70 mm SVL) than Sigalegalephrŋnus . The genus Phrŋnoidis is represent-ed by two large (> 70 mm SVL) semiaquatic toads, usually found on rocks along streams and rivers; the members of the Duttaphrŋnus (> 40 mm SVL) and Ingerophrŋnus (> 40 mm SVL) display terrestrial or somewhat riparian habits. The monotypic genus Pseudobufo is represented by a large (> 75 mm SVL) and aquatic species with completely webbed feet that inhabits the peat swamps of the Malay Peninsula, Borneo, and Eastern Sumatra.

Like all other Sundaland toad genera (characters in parentheses), the new genus possesses a visible or slightly visible tympanum. Sigalegalephrŋnus most closely resembles Ansonia ; however, the former lacks mandibular spines (mandibular spines present) and possesses combined femur and tibia lengths smaller than its SVL (SVL <femur and tibia lengths). Unlike Pelophrŋne, in Sigalegalephrŋnus Finger I projects beyond the webbing by two phalanges (reduced Finger I, with one or no phalanges projecting beyond webbing), and males possess nuptial excrescences with well-keratinized spicules (poorly spiculated with only slight keratinization or not keratinized at all). Unlike Rentapia , Sigalegalephrŋnus lacks paratoid glands (paratoids prominent). The new genus can be told apart from Ingerophrŋnus by the lack of well-defined parallel crests between the eyes (parallel crests prominent). Unlike Leptophrŋne, Sigalegalephrŋnus lacks enlarged tubercles at the base of each toe, between at the articulation of the first phalanx and metacarpus (large tubercles present). Additionally, males of L. cruentata are unique among Southeast Asian toads in having nuptial excrescences that are white and swollen on the first and second fingers; males of Sigalegalephrŋnus (and all other genera) have nuptial excrescences with no white and swollen tissue. Unlike Phrŋnoidis, Sigalegalephrŋnus has slender limbs (limbs robust) and toes that are less than half webbed (toes fully webbed, with the exception of the fourth). Unlike Pseudobufo —the only Sundaland toad with fully webbed toes— Sigalegalephrŋnus has toes that are less than half webbed.

Males of Sigalegalephrŋnus can be distinguished from all other toads in the region by the presence of an elongate inner metacarpal-thenar tubercle, which is as distinct and large as the outer metacarpal tubercle, and is located medially ( Fig. 2 ). Males of Leptophrŋne cruentata have an elongate and medially located inner metacarpal tubercle, but this is less distinct and noticeably smaller than the outer metacarpal tubercle, whereas Rentapia and Pelophrŋne lack the inner metacarpal tubercle altogether. Fingertips three and four of the new genus are truncated, reflecting arboreality as in Pelophrŋne, Sabahphrŋnus, Rentapia , and some species of Ansonia .

Etymology. —The generic name is derived from the name given by the indigenous Batak people of the Toba region in Sumatera Utara to life-sized wooden puppets called Sigale Gale. These puppets are used during the papurpur sepata funerary festivals to placate the spirits of the dead who have left no children behind. The suffix is derived from the masculine and Latinized Greek noun for toad, phrŋnos. The new genus, with a relatively large size compared with most arboreal toads in the region, lanky hands, and a wood-brown complexion, is evocative of the Sigale Gale.

Common name. —Puppet Toads.

Content. —Our phylogenetic analyses indicate the presence of two species within the new genus: S. mandailinguensis Smart et al. ; and S. minangkabauensis Smart et al.

Figures

FIG. 2.—Palmar (upper) and plantar (lower) surfaces of Sigalegalephrŋnus mandailinguensis (A; MZB 25736) and S. minangkabauensis (B; MZB 25738).