Amnihyla Richards, Mahony & Donnellan, 2025

Donnellan, Stephen C., Mahony, Michael J., Esquerré, Damien, Brennan, Ian G., Price, Luke C., Lemmon, Alan, Lemmon, Emily Moriarty, Günther, Rainer, Monis, Paul, Bertozzi, Terry, Keogh, J. Scott, Shea, Glenn M. & Richards, Stephen J., 2025, Phylogenomics informs a generic revision of the Australo-Papuan treefrogs (Anura: Pelodryadidae), Zoological Journal of the Linnean Society 204 : -

Amnihyla Richards, Mahony & Donnellan , gen. nov.

( Figs 9, 10)

ZooBank LSID: urn:lsid:zoobank.org:act:4A0ADBA7-AE39-43FC-A114-78063102556E Type species: Hyla (Litoria) arfakiana ( Peters & Doria, 1878) .

Content: 24 species— Amnihyla amnicola * (Richards, Tjaturadi, Krey & Donnellan, 2021) comb. nov., Amnihyla angiana* ( Boulenger, 1915) comb. nov., Amnihyla arfakiana * ( Peters & Doria, 1878) comb. nov., Amnihyla becki * ( Loveridge, 1945) comb. nov., Amnihyla brongersmai ( Loveridge, 1945) comb. nov., Amnihyla bulmeri * ( Tyler, 1968a) comb. nov., Amnihyla dorsivena * ( Tyler, 1968a) comb. nov., Amnihyla fuscula (Oliver & Richards, 2007) comb. nov., Amnihyla lakekamu ( Richards & Bickford, 2023) comb. nov., Amnihyla leucova * ( Tyler, 1968a) comb. nov., Amnihyla longicrus ( Boulenger, 1911) comb. nov., Amnihyla macki (Richards, 2001) comb. nov., Amnihyla megalops (Richards & Iskander, 2006) comb. nov., Amnihyla micromembrana * ( Tyler, 1963a) comb. nov., Amnihyla modica * ( Tyler, 1968a) comb. nov., Amnihyla napaea ( Tyler, 1968a) comb. nov., Amnihyla oenicolen * ( Menzies & Zweifel, 1974) comb. nov., Amnihyla pratti * ( Boulenger, 1911) comb. nov., Amnihyla rara ( Günther & Richards, 2005) comb. nov., Amnihyla rivicola * ( Günther & Richards, 2005) comb. nov., Amnihyla scabra ( Günther & Richards, 2005) comb. nov., Amnihyla spartacus * ( Richards and Oliver, 2006b) comb. nov., Amnihyla spinifera *( Tyler, 1968a) comb. nov., Amnihyla wollastoni * ( Boulenger, 1914) comb. nov.

Diagnosis: All Amnihyla can be diagnosed from Exochohyla , Nasutibatrachus , and Teretistes by the absence of a rostral spike; all except A. amnicola from Carichyla , Drymomantis , Exedrobatrachus , and Papuahyla by large pale vs. small pigmented ova ( A. amnicola can be diagnosed from Exedrobatrachus by toe and finger discs equal in size vs. smaller; and from Carichyla , Drymomantis , and Papuahyla by the presence of tubercles on the hindlimb vs. absence); from Drymomantis and Papuahyla by a Type 3 vs. Type 1 tadpole oral disc, and Type 6 or 7 vs. Type 1 overall tadpole morphology; from Hyalotos by pigmented vs. transparent tympanum; from Ischnohyla by Type 6 or 7 vs. Type 2A overall tadpole morphology; from Lathrana by frequency modulated vs. unmodulated calls, by medium duration vs. long duration calls, and by calls with few vs. medium number of notes; from Papuahyla by fusiform, oval, rectangular, spike, or teardrop vs. a right triangular call envelope shape; from Viridihyla by a highly variable dorsal pattern vs. a uniform green dorsum. Amnihyla , except A. amnicola , can be diagnosed from Kallistobatrachus by large unpigmented eggs vs. small or medium pigmented eggs. Amnihyla amnicola can be diagnosed from Kallistobatrachus by lacking bright colours ventrally and/or in axilla and groin. Refer to Tables 1 and 2.

Distribution and ecology: New Guinea and surrounding islands, lowland forests to alpine meadows. Arboreal or semi-aquatic frogs that breed in clear-flowing, often torrential, streams. All species for which eggs are known, with the exception of A. amnicola , have large unpigmented eggs. Tadpoles are known or presumed to have large, ventrally oriented suctorial mouthparts. Calls often with narrow frequency bands to enhance detection above the sound of running water.

Etymology: From the Latin amnis (a river) and Hyla Laurenti, 1768 , the earliest generic name for a tree frog, itself derived from Υλας ( Hylas ), companion of Hercules in Greek mythology. While the original Hylas was a boy, and Copland (1962) treated the generic name derived from Hylas as masculine (incorrectly emending numerous adjectival species epithets to match), the generic name is feminine in its original formation ( Myers and Stothers 2006) and remains so as the root for Amnihyla . The name alludes to the riverine habitat of the species in the genus.

Remarks: Amnihyla is the equivalent of the Litoria angiana , Litoria arfakiana , Litoria becki , Litoria bulmeri , Litoria dorsivena , Litoria leucova , and Litoria napaea Groups of Tyler and Davies (1978). Small to large New Guinea stream-dwelling frogs. The following nine species are all closely associated with clear-flowing streams and are included in Amnihyla in the absence of genetic data pending genetic material becoming available. Hyla brongersmai was not treated by Tyler and Davies (1978) but Menzies (2006) noted that its ‘habitat and morphology indicate that this species is correctly placed among the torrent breeders’. Oliver and Richards (2007) argued that based on its morphology and ecology Litoria fuscula is allied to the L. dorsivena species group. Richards and Bickford (2023) noted that the ecology of L. lakekamu ‘suggests that it is more likely to be related to the clade of torrent dwelling frogs including L. leucova ’. Litoria macki was described by Richards (2001) as a torrent dwelling species most similar to L. spinifera , a species within Amnihyla . Richards and Iskandar (2006) considered Litoria megalops to be most similar to L. micromembrana and L. modica , both within Amnihyla . Günther and Richards (2005) demonstrated that L. rara is closely related to L. rivicola within Amnihyla based on mitochondrial 12S rDNA nucleotide sequences, and that L. scabra is morphologically most similar to L. rivicola . Hyla napaea has large unpigmented eggs and was considered probably a ‘stream-breeding species’ (Tyler and Davies 1978). Tyler and Davies (1978) placed Hylella longicrus Boulenger, 1911 in their Litoria bicolor Group. With unpigmented eggs, a truncate vs. rounded snout and close association with clear-flowing streams it is clearly not in the Litoria bicolor Group, and we assign it tentatively to Amnihyla pending further studies.