Hyperolius phrynoderma Ahl, 1931a: 71.

Tillack, Frank, Ruiter, Ronald de & Roedel, Mark-Oliver, 2021, A type catalogue of the reed frogs (Amphibia, Anura, Hyperoliidae) in the collection of the Museum fuer Naturkunde Berlin (ZMB) with comments on historical collectors and expeditions, Zoosystematics and Evolution 97 (2), pp. 407-450 : 407

Hyperolius phrynoderma Ahl, 1931a: 71.

Syntypes.

ZMB 39000 and ZMB 77734-77736 (formerly part of ZMB 39000), "Zentrales Deutsch-Ost-Afrika" [Central German East Africa, Central Tanzania, see comment below] collected during the first "Deutsche Zentral-Afrika-Expedition", 1907-1908.

Present name.

Hyperolius cf. viridiflavus ( Duméril & Bibron, 1841).

Remarks.

Depicted in Ahl (1931b: 344, fig. 218). Another syntype, MCZ A-17643 with identical collecting data was sent in exchange to MCZ in 1932 ( Barbour and Loveridge 1946: 130). Laurent (1961: 83) erroneously presumed that the five subadult specimens inventoried under ZMB 13701 could be the types of Hyperolius phrynoderma , but these specimens were collected at “Bukoba” by Stuhlmann and do not correspond with the locality given by Ahl for the types. Ahl’s (1931a: 72) vague locality information for the H. phrynoderma types is probably wrong and mainly based on the transfer of the expedition name to a region, i.e. "Central German East Africa" which would be geographically equivalent to today’s central Tanzania. However, the zoological collections of this expedition mainly originate from northeast Tanzania, Rwanda and the adjacent Democratic Republic of the Congo, more precisely from the region between Bukoba on the western shore of Lake Victoria, Ischangi in the south of Lake Kiwu and Irumu in the Ituru Province of northeastern Democratic Republic of the Congo (see comments in Barbour and Loveridge 1946: 130; map in Schubotz 1909).

Currently, the status of this taxon is uncertain. In comparison to species in the H. marmoratus / Hyperolius viridiflavus group, the body is comparatively slender and the snout more pointed. Dorsal warts are distinct, and arranged very regularly, even in the single adult frog ( ZMB 39000). Juveniles of the H. marmoratus / Hyperolius viridiflavus group have warty skin, adults usually have smooth skin). Drewes (1997) described a superficially similar-looking frog from the Serengeti, Hyperolius orkarkarri , which is currently regarded as a synonym of H. glandicolor (see Channing and Howell 2006).

Under the leadership of Adolf Friedrich, Duke of Mecklenburg, the first "Deutsche Zentral-Afrika-Expedition" was carried out from 1907 to 1908, to scientifically investigate the area of the African Rift Valley (see also remarks on Hyperolius adolphi-friederici ).