A new genus of ranine frog (Anura: Ranidae) from Somalia B. T. Clarke Department of Zoology, British Museum (Natural History), London SW7 5BD Introduction Lanza (1978) described a new species of ranine frog from the Nogal Valley in northern Somalia and tentatively assigned it to the genus Hildebrandtia Nieden, 1907. However, he stressed that 'As the phylogenetic relationships between the various forms which have been included at one time or another under the name Rana are very questionable, I prefer to assign the new frog tentatively to Hildebrandtia rather than to a new genus'. Lanza conse-quently named his new species Hildebrandtia (?) largeni. In a recent survey of African ranine frogs (Clarke, 1981) based on 22 osteological characters, evidence emerged for the recognition of a new genus to accommodate H. (?) largeni, but a formal description was delayed pending the examination of further material of Lanza's species. The external morphology and osteology of additional material confirm the necessity to recognize the new genus. LANZARANA gen. nov. TYPE SPECIES. Hildebrandtia (?) largeni Lanza, 1978 : 232. DIAGNOSIS. (1) Small to moderate African ranine frogs, adult males 42-0^5-2 mm (n = 17); adult, gravid females 43-7-48-5 mm (n = 9) snout-vent length. (2) Skin of dorsum smooth or smooth with low pustules, no dorsolateral folds. (3) Males with external vocal sacs. (4) Fingers moderately long, 2nd shortest, 1st longer than or equal to 4th, 3rd longest. (5) Tips of fingers, 1st and 2nd rounded or slightly expanded; 3rd and 4th rounded or slightly to broadly expanded, truncate, 3rd showing most extreme condition. (6) Inner metatarsal tubercle moderately well developed not compressed. (7) Outer metatarsal tubercle present, distinct. (8) Outer metatarsals not separate, bound in a fleshy sole. (9) Nasals reduced, slip-like, widely separated. (10) Occipital canal absent. (11) Otic plate rudimentary. (12) Zygomatic ramus of squamosal shorter than otic ramus. (13) Preorbital process of pars fascialis of maxilla well developed, rectangular in lateral view. (14) Anterior end of maxilla convex. (15) Pterygoid process of maxilla absent. (16) Anterior process of prevomer moderate, separated from mesial maxilla/premaxilla articulation by a short gap. (17) Palatines present. (18) Distal end anterior ramus of pterygoid moderately long, separated from lateral border of planum antorbitale by short gap. (19) Cervical cotyles slightly separately mesially, type II sensu Lynch, 1971. (20) Base of omosternum moderately forked; greatest space between the arms is once to twice the width of one arm, state 2 of Liem, 1970. (21) Clavicles reduced, widely separated mesially. (22) Sternal style a short compact bony element, tapering slightly anteriorly to posteriorly. (23) 8th presacral and sacral vertebrae fused. (24) Dorsal protrub-erance of ilium not or slightly differentiated from dorsal prominence, smooth surfaced, confluent with dorsal ilial crest. (25) Distal ends of terminal phalanges of fingers slightly, moderately or markedly expanded, truncate, see (5) above; of toes cone-like. ECOLOGY AND HABITAT. Specimens collected by Lanza were found in undulate subdesert regions characterized by grass, perennial herb and subshrub steppe. The type series of six males from ca. 10 km N of Garoe were found calling near a soil depression with shallow Bull. Br. Mus. nat. Hist. (Zool.)43 (3) : 179-183 Issued 30 September 1982
BioStor
