Thursday, September 12, 2013

[Herpetology • 2002] Kaloula walteri | Walter's Narrow-mouthed Frog • A New Species of Narrow-mouthed Frog (Amphibia: Anura: Microhylidae; Genus Kaloula) from the Mountains of southern Luzon and Polillo Islands, Philippines

Fig. 1. Color pattern variation in live Kaloula walteri, photographed on Mt. Banahao, Luzon Island. Light phase, tan dorsum with dark marbling

Kaloula walteri Brown, Diesmos & Alcala, 2002

We describe a new species of narrow-mouthed frog of the genus Kaloula from the volcanic mountains of southern Luzon Island (Mt. Banahao, Mt. Isarog, and Mt. Mayon) and adjacent Polillo Island, Philippines. On the volcanoes of southern Luzon, the new species is found in habitats ranging from small dry stream beds to stationary pools of rivers in mid- to upper montane primary forest. On Polillo Island, the new species has been found near quiet streams in selectively logged primary forest and second growth near sea level. The new species presumably is allied to Kaloula rigida (a forest species endemic to northern Luzon Island) and to Kaloula picta (a more widespread Philippine endemic that is found in a variety of habitats) as indicated by possession of narrow disks on the digits and by the presence of supernumerary tubercles on the palmar surface of the manus. It differs from these species by its smaller body size, reduction of webbing on toes, absence or extreme reduction of outer metacarpal tubercles, and by characteristics of the advertisement call.

Etymology: The new species is named in honor of Walter C. Brown in recognition of his immense contributions to our knowledge of the systematics, zoogeography, and ecology of Philippine amphibians and reptiles. Suggested Common Name: Walter's narrow-mouthed frog

Ecology, habitat, and life history. Specimens of K. walteri have been observed or collected in riparian habitats ranging from lowland dipterocarp forest to midmontane closed-canopy rain forest (sensu Whitmore, 1984). On Mt. Banahao, the new species has been observed in habitats at elevations of 650-950 m ranging from small (= 3 m wide) dry stream beds to larger rivers (> 6 m wide) during the dry season (observed in March and April) when water levels decline and large stationary pools form (Fig. 5). The single specimen from Mt. Isarog was collected at an elevation of 990 m, and Mt. Mayon specimens were collected at 650 m. The specimen from Polillo was collected at approximately 25 m above sea level in well-regenerated secondary forest. Specimens at this locality have been heard calling near clearings and even on edges of agricultural areas adjacent to forest (V. Yngente, pers. comm.)


Other sympatric species of anurans include K conjuncta conjuncta, Limnonectes macrocephalus, Limnonectes woodworthi, Rana luzonensis, Rana similis, Philautus surdus, Platymantis banahao, Platymantis corrugatus, Platymantis dorsalis, Platymantis luzonensis, Platymantis montanus, Platymantis indeprensus, and Platymantis pseudodorsalis. Other amphibians known from Mt. Banahao (Diesmos, 1998; unpubl. data), that we have not found at the specific type locality, include Occidozyga laevis, Rana erythraea, Polypedates leucomystax, Rhacophorus bimaculatus, Rhacophorus pardalis, and two additional undescribed species of Platymantis. On Mt. Isarog, the new species also is sympatric with Platymantis isarog (Brown et al., 1997), and an undescribed species of Platymantis (unpubl. data) and on Polillo Island, Rhacophorus appendiculatus, Platymantis polillensis, Platymantis sp. (of uncertain taxonomic status, possibly conspecific with P. luzonensis) and Rana (= Fejervarya) vittigera also have been recorded sympatrically (Hampson, 1999a,b; ACD and RMB, pers. obs.). 

Diesmos, A.C., Brown, R.M. and Alcala, A.C. 2002. A New Species of Narrow-mouthed Frog (Amphibia: Anura: Microhylidae; Genus Kaloula) from the Mountains of southern Luzon and Polillo Islands, Philippines. Copeia. 1037-1051.