Description
Xenorhina wiegankorum is a medium sized frog described from five male specimens with a snout-urostyle length range of 32.0 - 35.7 mm. The head is broader than long with an acuminate snout that protrudes in the profile. There are well-developed vomerine spikes on each vomeropalatine bone. The dorsolaterally positioned nostrils are located close to the snout-tip and are not visible from the ventral view. The intranarial distance is much smaller than the eye-nare distance. The internarial distance is smaller than the distance between the nostrils and the eyes. The loreal region has an oblique shape and there is no canthus rostralis. The eye diameter is equal or slightly greater than the tympanum diameter. The tympanum is strongly defined in preservative, but less so in life. A well-developed supratympanic fold is present, extending from behind the eye to the insertion of the forelimb. There are small, scattered tubercles on the lateral regions of the body and dorsal surface of the limbs. The tip of the snout, especially on the ventral portion, has many small elevations. The ventral surface is smooth. The hands do not have any palmer tubercles. The unwebbed fingers are short with relative lengths of 3 > 4 > 2 = 1, and end in unexpanded tips with circum-marginal grooves. The subarticular tubercles of the hands are barely defined. The tibia is 44 - 47% of the body length. The planter also does not have tubercles. The unwebbed toes have relative lengths of 4 > 3 > 5 > 2 > 1, and end in acuminated tips that are wider than the penultimate phalanges and have circum-marginal grooves. The toes also have barely defined subarticular tubercles (Günther and Richards 2021).

DIAGNOSIS:

This species is distinguished from others in the genus of the same size by limb length, coloration, geography, and/or advertisement call characters. Specifically, X. wiegankorum eyes are slightly larger than X. huon and the eye-naris distance relative to the body size is slightly longer than X. fuscigula. Xenorhina wiegankorum has proportionally longer legs than X. fuscigula and X. huon, but shorter than X. subcrocea. Xenorhina wiegankorum has similar body size and proportions to X. lacrimosa and X. zweifeli, however, they can be differentiated by coloration, patterning and texture. Specifically, X. wiegankorum is a more uniform a light olive-brown and more rugose dorsum in life while X. lacrimosa is more variable with brown or grey background colors. Xenorhina zweifeli has a brown supratympanum stripe that X. wiegankorum lacks. On the posterior and ventral surfaces, X. lacrimosa a dark brown patch around the vent and deep orange to grey-brown ventrum with white spot whereas X. wiegankorum has a more yellow ventrum. Other species with differentiating ventrums are X. huon, which has dark flecking on the ventrum, and X. subcrocea, which has dark reticulations, neither of which are found in X. wiegankorum. Xenorhina huon is also found in a different part of the country than X. wiegankorum. With regards to call, the call series in X. wiegankorum is longer than the single call of X. fuscigula and X. zweifeli, but shorter than the call series of X. lacrimosa. Furthermore, X. zweifeli may call during the day, but X. wiegankorum is only known to call at night. The number of calls in the call series is greater in X. wiegankorum than in X. lacrimosa. The call interval within a series and the series repetition rate in X. wiegankorum is greater than X. lacrimosa but less than X. subcrocea. However, X. lacrimosa has a longer call length (Günther and Richards 2021). Xenorhina wiegankorum has also been compared to X. ventrimaculata with the focal species being larger, having longer tibias and tarsi relative to their body lengths, and having a call with a longer call series, shorter calls with a slower repetition rate, and a lower dominate frequency (Gunther et al. 2021).

COLORATION:

In life, the dorsal surface is light olive-brown or grey with a lumbar area that lacks spots and a yellowish mid-dorsal line. The tubercles have whitish tips on the lateral surface. There is also a yellow line along the hind limbs to the tarsi. There are no dark spots on the posterior thighs near the vent. The abdomen, thighs, arms and the shanks on the ventral surface are melon-yellow color with some hard to see whitish spots. The chest and throat surface are also a melon-yellow color, but with off-white spots and beige-grey spots. The fingers as well as the palm are grey on the ventral surface. The ventral side of the hind limb is brown where it touches the surface of the ground and the toes have a grey ventral surface. The irises are blackish and speckled with gold (Günther and Richards 2021).

In preservative, the dorsal surface becomes a pastel violet that may have darker areas and with inconspicuous white-tipped tubercles. The snout tip is grey. The light mid-dorsal line may be absent. The dorsal surface of the limbs may be lighter brown with dark brown stripes or spots. The posterior surfaces of the thighs are mostly brown but may be blackish around the vent. The ventral surface becomes an ivory color, and the patterning on the chest and throat becomes a brown-beige color (Günther and Richards 2021).

VARIATION:

There is some variation in coloration with the dorsal surface ranging from grey to brown. Patterning is also variable. At the time of the species description, no females were collected so sexual variation could not be determined (Günther and Richards 2021).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Papua New Guinea

View distribution map in BerkeleyMapper.

This species is found in the foothills rainforest of the upper Strickland River basin in Western Province, Papua New Guinea between the altitudes of 330 - 950 m (Günther and Richards 2021).

Life History, Abundance, Activity, and Special Behaviors
Males call from under leaf litter or slightly below the soil surface at night, during or just after heavy rain. The deep, unpulsed call has “popping” notes that increase in volume and pitch over the call series. At air temperatures between 21.0 - 25.0 °C the full call series lasted 13.8 - 18.1 seconds and consisted of 22 - 39 calls, with each individual call lasting 60 - 104 ms, for a call repetition rate of 1.71 - 2.15 calls/second. The call begins abruptly at a high amplitude that gradually decreases. There are 2 - 7 harmonics, and the fundamental and dominant frequencies are 0.55 kHz (Günther and Richards 2021).

Comments
This species was described based on morphology and advertisement call (Günther and Richards 2021).

References
Günther, R., and Richards, S. (2021). Description of six new species of Xenorhina Peters, 1863 from southern Papua New Guinea (Amphibia, Anura, Microhylidae). Zoosystematics and Evolution, 97(2), 355–382. [link]

Günther, R., Dahl, C., and Richards, S. J. (2021). Description of a new Xenorhina species (Anura, Microhylidae) from northwestern Papua New Guinea. Vertebrate Zoology, 71, 621-630. [link]

Species Account Citation: AmphibiaWeb 2025 Xenorhina wiegankorum <https://amphibiaweb.org/species/9414> University of California, Berkeley, CA, USA. Accessed May 12, 2025.

Citation: AmphibiaWeb. 2025. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 12 May 2025.

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