Nyctimystes Stejneger 1916: 85

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 : -

Nyctimystes Stejneger 1916: 85

( Figs 24, 25)

Type species: Nyctimantis papua Boulenger, 1897 , by monotypy.

Content: 32 species— Nyctimystes avocalis Zweifel, 1958 , Nyctimystes bivocalis Kraus, 2012a , Nyctimystes calcaratus Menzies, 2014 , Nyctimystes cheesmani * Tyler, 1964a , Nyctimystes cryptochrysos Kraus, 2012b , Nyctimystes daymani Zweifel, 1958 , Nyctimystes disruptus * Tyler, 1963b , Nyctimystes eucavatus Menzies, 2014 , Nyctimystes fluviatilis * Zweifel, 1958 , Nyctimystes foricula * Tyler, 1963b , Nyctimystes granti ( Boulenger, 1914) , Nyctimystes gularis Parker, 1936 , Nyctimystes humeralis * ( Boulenger, 1912) , Nyctimystes intercastellus * Kraus, 2012a , Nyctimystes kubori * Zweifel, 1958 , Nyctimystes kuduki Richards, 2007b , Nyctimystes latratus Menzies, 2014 , Nyctimystes montanus ( Peters & Doria, 1878) , Nyctimystes myolae Menzies, 2014b , Nyctimystes narinosus Zweifel, 1958 , N. obsoletus ( Lönnberg, 1900) , Nyctimystes ocreptus Menzies, 2014b , Nyctimystes oktediensis * Richards & Johnston, 1993 , Nyctimystes papua * ( Boulenger, 1897a) , Nyctimystes perimetri Zweifel, 1958 , Nyctimystes persimilis Zweifel, 1958 , Nyctimystes pulcher * ( Wandolleck, 1911) , Nyctimystes semipalmatus * Parker, 1936 , Nyctimystes trachydermis Zweifel, 1983 , Nyctimystes traunae Menzies, 2014 , Nyctimystes tyleri Zweifel, 1983 , Nyctimystes zweifeli * Tyler, 1967 .

Diagnosis: Nyctimystes can be diagnosed from all other pelodryadids by a combination of a vertical pupil, patterning on the palpebral membrane, and large unpigmented eggs. It can be diagnosed further from Sandyrana by the absence vs. presence of the m. extensor brevis medius digiti IV; from Sylvagemma by tadpole oral disc Type 6A (oral disc reported for only two species of Nyctimystes ) vs. Type 1A. Refer to Tables 1 and 2.

Distribution and ecology: Arboreal frogs that are found in New Guinea and surrounding islands. These frogs are found across a wide elevational range from near sea level to 3200 m a.s.l. and have the highest species diversity in lower montane habitats ( Menzies 2006). All species for which reproduction is known produce large unpigmented eggs that are laid in clear-flowing, often torrential, rocky streams. Tadpoles of only two species have been documented ( Table 1); these have large, ventrally oriented suctorial mouthparts; all species in the genus are expected to exhibit this character.

Etymology: From the Greek νυκτός (nyktos), the genitive singular of νύξ (nyx, the night) and μῠ́στης (mystes, a mystic, one who has been initiated). The name is a parallel to the genus Nyctimantis , from which Stejneger separated the species ( Meagher 2013). However, Stejneger assumed that mantis was from the Greek word meaning seer or prophet, instead of the alternate meaning of a tree frog, though linked to the first meaning through the belief that the tree frog was able to predict the weather ( Liddell and Scott 1897). The gender is masculine.

Remarks: Nyctimystes is found only on the main island of New Guinea and the high islands of the D’Entrecasteaux group and the Louisiade Archipelago in the south-east. Few species have been recorded from the western half of New Guinea to date but whether the difference in species diversity with the eastern half of the island reflects a biogeographic pattern or sampling opportunities remains to be determined ( Menzies 2014a). Nyctimystes oktediensis was synonymized with N. disruptus by Menzies (2014b) but it differs from that species in aspects of size and colour pattern (unspotted vs. spotted), and the two species are deeply divergent genetically ( Fig. 1). Numerous species remain to be described ( Menzies 2006; S. Richards, personal observations).

Species included in Nyctimystes in the absence of genetic data are placed in this genus on the basis of having a vertical pupil, a palpebral reticulum and, where known, large, unpigmented eggs.