Callulops valvifer (Barbour 1910)

Callulops valvifer is a large microhylid frog with a snout vent length of 72.3 mm for males and 81.4 mm for females. The narrow head is not distinct from the slightly wider body. In the dorsal view, the snout is truncated but rounded and protrudes slightly in the lateral view. In adults, the eyes are medium-sized. The distance between the nostrils is wider than the distance between the eye and the nostril. Nostrils are near the snout and directed laterally. The tympanum is distinct with a supratympanal fold that starts at tympanum and ends forearm insertion. The limbs of the frog are robust, and there are strong hind limb muscles. The inner metacarpal tubercle is very visible, while the palmar and subarticular tubercles are large but not visible. Relative finger lengths are 3 > 4 > 2 > 1. The digital discs are larger than the penultimate phalanges, and they possess terminal grooves. Circum-marginal grooves are well developed on all fingers and toes. The discs of the fingers and toes are roughly the same size, or the finger disks are slightly smaller. Relative toe lengths are 4 > 3 > 5 > 2 > 1. The skin is smooth on both the dorsal and ventral surfaces of the frog. Juvenile frogs are similar in biometrics, but have slightly larger eyes (Günther 2013).Callulops valvifer can be differentiated from other Callulops frogs by its large size, short legs, well developed circum-marginal grooves on all fingers and toes, short internarial distance relative to eye-naris distance, and advertisement call (see “Life History” section for more info on call; Günther 2013).In life, both males and females are uniformly brown, with light grey flanks and ventral surfaces. However, the male is slightly darker than the female. Both sexes have a golden iris with black veins, and the female possesses a light-blue patch on the posterior and anterior corners of the eye. In preservative, the dorsal surfaces of the frogs are uniformly dark brown (male) and medium brown (female). In females, the ventral surface in preservative is a light grey-brown; the males are slightly darker. In both sexes, the ventral portion of the throat is darker than the surrounding ventral surfaces. Both sexes have a light spot on the dorsal surface of all finger and toe discs.Juveniles in preservative show different coloration than adults. The dorsal surfaces of the juvenile, as well as the sides, are dark brown (more likely black in life) speckled with abundant whitish spots. The venturm is also brownish (also likely black in life) with white spots (Günther 2013). The variation that exists within the species is between the sexes (with males darker than females) and between adults and juveniles (juveniles possess spots, adults have uniform coloring; Günther, 2013).The modern species authority for this species is: Günther, Rainer. 2013. From a dwarf to a giant: Revalidation of Callulops valvifer (Barbour 1910), (Amphibia, Anura, Microhylidae). Zootaxa, 3641(3), p 271-281. However it was first described by Barbour, T. (1910). A new genus of Amphibia Salientia from Dutch New Guinea. Proceedings of the Biological Society of Washington, 23, 89–90. This taxon was originally named Pomatops valvifera based on one juvenile specimen, and is also synonymised with Asterophrys, but recent morphological research and field work has reclassified this frog as Callulops valvifer (Günther 2013).Callulops valvifer is the sister taxon of Callulops omnistriatus. This was determined using 12S rRNA and 16S rRNA data extracted from the specimens (Günther 2013).

Callulops valvifer is found in humus soils, at approximately 300 m to 900 m in elevation. The range is restricted to the Indonesian Fakfak Mountains, in areas of mostly secondary forest, where the canopy is closed partially (Günther 2013).

These frogs may retreat into hollows in the ground when threatened. The calls are very loud, and tend to drown out other nearby amphibian calls. Advertisement calls are 4-8 loud, harsh, croaking notes; With the exception of the first note, all notes are 192-261 milliseconds in duration. The notes repeated at a rate of 1.24-1.30 notes per second, at a dominant frequency of 1.1 kHz (Günther 2013).

There is currently no listing on the IUCN Red List of Threatened SpeciesTM for this species (IUCN 2012).