Ischnohyla 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 : -

Ischnohyla Richards, Mahony & Donnellan , gen. nov.

( Fig. 17)

ZooBank LSID: urn:lsid:zoobank.org:act:7E77AC9B-CD9C-40B3-B7CD-1F1CBC5F492E Type species: Litoria nigropunctata (Meyer, 1874) .

Content: Five species— Ischnohyla daraiensis * ( Richards, Donnellan & Oliver, 2023) comb. nov., Ischnohyla gracilis * ( Richards, Donnellan & Oliver, 2023) comb. nov., Ischnohyla nigropunctata * (Meyer, 1874) comb. nov., Ischnohyla umarensis ( Günther, 2004a) comb. nov., Ischnohyla vocivincens ( Menzies, 1972) comb. nov.

Diagnosis: Ischnohyla can be diagnosed from its sister taxon Exochohyla by the absence of a heel and rostral spikes, the occurrence of large unpigmented ova vs. either the presence of small pigmented ova (one species) or medium-sized pigmented ova (two species) or large unpigmented ova (two species), no note rate change across the call vs. present. Refer to Tables 1 and 2.

Distribution and ecology: New Guinea and surrounding islands. Arboreal frogs that are found in forests, predominantly in lowland and foothill habitats.At least one species( gracilis ) glues unpigmented eggs to leaves above forest pools or pools within slow-flowing streams, and one ( vocivincens ) lays small, pigmented eggs in water.

Etymology: From the Greek ισΧνός (ischnos, weak, thin, or meagre) and the frog genus name Hyla , alluding to the slender body form of this genus. The gender, based on Hyla , is feminine.

Remarks: Ischnohyla is the equivalent in part ( I. nigropunctata and I. vocivincens ) to the Litoria nigropunctata Group of Tyler and Davies (1978). Litoria obtusirostris Meyer, 1874 was described from Ansus, Yapen Island, the same type locality as I. nigropunctata . It is the same size as that species, and with the exception of being reported to have exceptionally long legs—possibly in error—and poorly developed vomerine teeth there is little to distinguish the two taxa (colour variation in nigropunctata is more extensive than previously recognized). Given that the holotype (and only known) specimen was destroyed during the Second World War, and that extensive collections of pelodryadids on Yapen Island in recent decades have failed to detect a species distinct from nigropunctata (D. Price, personal communication, R. Günther, personal observations), we tentatively place this species in the synonymy of I. nigropunctata .

We placed I. vocivincens in Ischnohyla because of Menzies’ (1972) diagnosis of a Litoria nigropunctata group that included both I. nigropunctata and I. vocivincens , the only two species of Ischnohyla described at that time. We also placed L. umarensis in Ischnohyla following Menzies’ (2006) placement of this species in the L. nigropunctata ‘complex’. A robust determination of these species’ relationships requires molecular genetic evidence.

Kallistobatrachus Richards, Mahony & Donnellan , gen. nov.

( Fig. 18)

ZooBank LSID: urn:lsid:zoobank.org:act:07817ADB-A3E8-4B1FB97F-86293 EBFA 986 Type species: Hyla iris Tyler, 1962 . 1897 .

Content: Eight species— Kallistobatrachus aplini * ( Richards & Donnellan, 2020) comb. nov., Kallistobatrachus beryllinus * (Richards & Donnellan, 2023) comb. nov., Kallistobatrachus chloronotus * ( Boulenger, 1911) comb. nov., Kallistobatrachus haematogaster * ( Richards, Donnellan & Oliver, 2023) comb. nov., Kallistobatrachus iris * ( Tyler, 1962) comb. nov., Kallistobatrachus lisae * ( Richards, Donnellan & Oliver, 2023) comb. nov., Kallistobatrachus majikthise * ( Johnston & Richards, 1994) comb. nov., Kallistobatrachus ollauro ( Menzies, 1993) comb. nov.

Diagnosis: Kallistobatrachus can be diagnosed from Lathrana by medium vs. short call duration and by variable vs. constant pulse rate; from Nasutibatrachus and Teretistes by the absence of a rostral spike vs. the presence in males only; and further from Teretistes by medium vs. high call dominant, fusiform or teardrop or spike vs. triangular call envelope shape and from Viridihyla by small to medium vs. large eggs, variable dorsal pattern (all species except K. beryllinus ) vs. uniform green dorsum ( Figs 18, 33). Refer to Tables 1 and 2.

Distribution and ecology: New Guinea lowland to montane arboreal frogs that are found in association with ponds. Some,

and probably all, lay eggs on leaves over water (Richards et al. 2023).

Etymology: From the Greek κάλλιστος (kallistos, very beautiful) and βάτΡαΧος (batrachus, frog), alluding to the beautiful coloration of the species. Both the original batrachos and the Latinized batrachus are masculine (Article 30.1.3).

Remarks: Kallistobatrachus is the equivalent in part ( K. chloronota ) to the Litoria bicolor Group and in part ( K. iris ) to the L. nigropunctata Group of Tyler and Davies (1978).

We here emend the specific epithet chloronota to chloronotus . The name refers to the green dorsum of the species, using the Greek notos (back) for the name. While it could be considered the name is being treated as a noun, the Greek noun ‘back’ is noton (neuter) or notos (masculine). There is no feminine form (nota is the plural of both noton and notos). Hence, by using the term nota in combination with the original feminine Hylella, Boulenger (1911) was using gender agreement to change the original source word into a Latinized feminine form, so it could be argued that he was using it as an adjective (green-backed).

We have conservatively placed Hylella chloronota Boulenger in Kallistobatrachus despite its sister relationship with Teretistes in the nuclear phylogenetic analysis ( Fig. 2), which together are the sister to the other species of Kallistobatrachus . Kallistobatrachus chloronotus lacks a rostral spike, the presence of which is diagnostic for Teretistes , but we are unable on the available data to diagnose it from the remainder of Kallistobatrachus . Resolution of the generic allocation for Kallistobatrachus chloronotus awaits more comprehensive phenotypic dataandtheinclusionof Lathrana (thesisterlineageof Teretistes inour mitochondrial phylogeny, Fig. 1) in the nuclear gene phylogenomic analysis. Although genetic data are not available for L. ollauro that species is placed in Kallistobatrachus on the basis of its overall morphology,likely breeding strategy (eggs fixed to leaves over water), and its proposed relationship to L. iris byMenzies (2006).

While as a general principal we have used the first named species to be the type species for genera erected herein, we depart from this practice for Kallistobatrachus in view of the uncertainty for the relationships of Hylella chloronota Boulenger 1911 and instead instate Hyla iris Tyler 1962 as the type species.