Thursday, January 23, 2014

[Herpetology • 2014] Chiromantis inexpectatus | Bornean opposite-fingered Tree Frog • First Record of the Tree-Frog Genus Chiromantis from Borneo with the Description of a New Species (Amphibia: Rhacophoridae)



We record a tree frog of the genus Chiromantis for the first time from outside the Southeast Asian continent and describe it as a new species, Chiromantis inexpectatus. The new species from the Malaysian state of Sabah, Borneo, is a small-sized Chiromantis (male snout-vent length ca. 22 mm), and is distinguished from all other members of the genus by the combination of the following morphological characteristics: dark stripes absent, but dark spots present on dorsum; a dark-brown lateral band present from snout tip to half of body, bordered ventrally by white stripe; third and fourth fingers less than half webbed; third finger disk wider than tympanum diameter; and inner metatarsal tubercle present. Significance of findings of this species from Borneo Island, as well as phylogeny and breeding habit of the genus Chiromantis, are briefly discussed.

 Keywords: Chiromantis inexpectatus , mitochondrial phylogeny, Southeast Asia, taxonomy, zoogeography


Chiromantis inexpectatus sp. nov.
Bornean opposite-fingered Tree Frog

Etymology: The specific name is a Latin adjective, referring to the fact that the occurrence of the genus on the island of Borneo, where the new species was found, was unexpected.

Range: Known from the type locality, Camel Trophy of the Maliau Basin Conservation Area, Sandakan Division, State of Sabah, Malaysian Borneo.

Natural history: In the type locality, Camel Trophy, two adult males and a metamorphosing juvenile of the type series were simultaneously found at night perching each on a leaf of low trees (< 1 m) extending above the surface of a shallow pool (3–5 m × 10 m). The air temperature before the time of finding was 24°C. No tadpoles were found in the pond nor eggs on overhanging leaves of trees. Early March may not be a breeding season since males were not calling, but is surely in the season of metamorphosis as evidenced by the presence of a juvenile with a degenerating tail. Frogs found together with the new species included Rhacophorus borneensis, Kurixalus appendiculatus, Polypedates macrotis (Boulenger, 1891), and Microhyla petrigena Inger and Frogner, 1979.


Masafumi Matsui, Tomohiko Shimada and Ahmad Sudin. 2014. First Record of the Tree-Frog Genus Chiromantis from Borneo with the Description of a New Species (Amphibia: Rhacophoridae). Zoological Science. 31(1):45-51. doi: http://dx.doi.org/10.2108/zsj.31.45