Muhammad F. Fauzan, Eric N. Smith, A. A. Thasun Amarasinghe, Achmad Farajallah, Asrael Racho, Masafumi Matsui & Amir Hamidy

Abstract. The fauna of Indonesia’s Lesser Sunda and eastern Java areas harbour lineages of Leptobrachium that have been historically assigned to L. hasseltii Tschudi, 1838. Here, using an integrative dataset—mtDNA (12S–tRNA^Val–16S; 1,979 bp), adult and larval morphology, and advertisement calls—we delimit and describe a new species from Buleleng (Bali) and Kediri (East Java). Phylogenetic analyses (ML/Bayesian) recover two well-supported clades within L. hasseltii sensu lato: (1) West–Central Java and southern Sumatra (true L. hasseltii) and (2) Bali–East Java (new species), with 16S uncorrected p-distance 3.2–5.2% to L. hasseltii. Morphologically, the new species differs from L. hasseltii by the combination of brown iris with a light-blue scleral arc (eye fully open), very large oval femoral glands (dark edged), no vomerine teeth and rictal glands, distinctive dorsal pattern (dark blotches with paired transverse bars) and ventral patterning, and tadpoles having LTRF 7(1–6)/5(1–4) versus 5(1–4)/5(1–4) in L. hasseltii. The advertisement call is an elongated series of short barks followed by low-frequency squawks and differs markedly in temporal structure from L. hasseltii. We discuss biogeographic implications and provide an IUCN preliminary assessment following current guidelines.

Key words. Amphibia, bioacoustics, Leptobrachium hasseltii, morphology, phylogeny

Read article here: RBZ-2026-0007