We describe a new species of torrent-dwelling ranid frog of the genus Meristogenys from the Crocker Range, western Sabah, northern Borneo. The new species, Meristogenys maryatiae, differs from congeners by the combination of: small body, males 31-37 mm and females 65-66 mm in snout-vent length; head narrower than long; eyes moderate, diameter subequal to snout; iris unicolored; legs long; ventral surface of tibia without heavy pigmentation; rear of thigh blotched dark brown and cream; toes fully webbed; outer metatarsal tubercle present; larval dental formula 7(4-7)/6(1).
We describe a new species of cascade frog of the genus Rana, from west Malaysia. Rana monjerai, new species is a medium-sized frog of the subgenus Odorrana (SVL of males, 38-43 mm; of one female, 75 mm), and is distinguished from all other members of this subgenus by the combination of: white lip stripe, dorsolateral fold, full web on the fourth toe, vomerine teeth, gular vocal pouch and relatively large tympanum in males, no dorsal marking, no clear light spots on rear of thigh, first finger subequal to second, finely tuberculated dorsum, and unpigmented ova. The significance of finding this species from peninsular Malaysia is discussed.
Although the crab-eating frog Fejervarya cancrivora is one of the most widely distributed species in Asian region, taxonomic relationships among different populations remain unclarified. In this study, we attempted to elucidate the taxonomic status of F. cancrivora from Indonesian and other Asian populations. Five populations of F. cancrivora from Selangor (Malaysia), Cianjur (Java, Indonesia), Trat (Thailand), Khulna (Bangladesh), and Makassar (Sulawesi, Indonesia) were morphologically observed and subjected to crossing experiments. Principal component and clustering analyses revealed that these five populations could be organized into three groups corresponding to three observed morphological types: a Selangor and Cianjur group (large-type), a Trat and Khulna group (mangrove-type), and a Makassar group (Sulawesi-type). The limited crossing experiments revealed that hybrids between Selangor females and Cianjur and Trat males developed normally, whereas hybrids between Selangor females and Khulna males showed incomplete gametic isolation. Histological observations of the testes of mature males revealed the presence of pycnotic nuclei in the hybrids between Selangor females and Khulna males in addition to normal bundles of spermatozoa. In contrast, no pycnotic nuclei were observed in the Selangor controls. Although meiotic metaphases in the controls were normal, those in hybrids showed several abnormalities, such as the appearance of univalents and an increase in rod-shaped bivalents. Based on our findings from the morphological observations and crossing experiments, we conclude that each of three identified types represents a distinct species. We propose that the large-type is F. cancrivora, the mangrove-type is F. moodiei, and the Sulawesi-type represents an undescribed species.
Two forms of Staurois that are differentiated by body size occur parapatrically in the Crocker Range, Sabah, Borneo. Analyses of a total of 1,499 bp of the mitochondrial cytochrome b, 12S rRNA, and 16S rRNA genes revealed that the two forms could be completely split genetically. The two forms could be also clearly differentiated morphologically, not only by snout-vent length but also by the relative sizes of snout, eye, and finger disk. Comparisons of the two forms with all known species of the genus revealed the large and small forms to be S. tuberilinguis and S. parvus, respectively. The latter species has long been synonymized with the former, but we here consider them to represent different species.
A cryptic Bornean torrent frog of the genus Meristogenys, which is divergent genetically and morphologically from all known congeners, is described from mountain streams of western Sarawak, East Malaysia (Borneo). The species occurs sympatrically with the type species of the genus, M. jerboa, but apparently differs from it in adult coloration and larval morphology, such as keratodont formulae and glands in tail fins. Females of the new species possess much larger and fewer eggs than in sympatric M. jerboa, suggesting significantly different reproductive traits between these species. A key to larvae of known species of the genus is provided.