A Phylogenetic Analysis of the Hyperoliidae (Anura): Treefrogs of Africa, Madagascar, and the Seychelles Islands Robert C. Drewes Introduction The hyperoliid treefrogs of Africa, Madagas-car, and the Seychelles Islands are a fascinating, colorful, and diverse group. Although they are nearly as varied as the treefrogs of the Neotrop-ics, they are less numerous; approximately 219 species are presently recognized. Adults range in body size from the diminutive, high-altitude, 1 5-mm-long reed frog, Hypewlius minutissimus, to the West African arboreal Leptopelis macrotis (84 mm). Most species are arboreal; however, there are terrestrial savanna species (most mem-bers of the genus Kassina), terrestrial highland grass dwellers {Chrysobatrachus). rock dwellers (A", parkeri), inhabitants of floating vegetation {Cryptothylax), and fossorial forms {Leptopelis bufonides, L. bocagei, and perhaps Kassinafusca and K. wealei). Most African treefrogs inhabit the tropics, wherein the species attain the greatest diversity, especially in West Africa. Representatives are present on the tip of the Cape of Good Hope and as far north as the arid, semidesert regions of southern Niger (Kassina fused) and the Somali Horn (A', parkeri). Many species are brilliantly marked with stripes, saddles, and blotches of contrasting colors (e.g., many species of Hypewlius, terrestrial species of Kassina, some Afrixalus, Kassinula, and Heteri.xalus); others are fairly uniform in coloration (e.g., Kassina fusca, K. kuvangensis, most Leptopelis, Tachycnemis, Cryptothylax, Acanthixalus, and Opisthothylax). Some species exhibit "flash patches"— areas of contrasting and perhaps disruptive color (usually red or yellow) most often on the posterior surfaces of the thigh or in the inguinal region {Tornierella, Phlycti-mantis, some arboreal Kassina, some Hypero-lius). Reproductively, African treefrogs are quite di-verse. Although direct development has not been observed, hyperoliids exhibit a broad spectrum of egg deposition sites, including glued leaf nests {Afrixalus. Opisthothylax), holes in trees {Acan-thixalus), holes dug in the ground {Leptopelis, and sometimes Tachycnemis), as well as the more familiar aquatic sites (some Hypewlius, Kassina, Tornierella). Tadpoles are varied morphologi-cally, and some are capable of terrestrial loco-motion {Leptopelis). Adult frogs of one montane species, Chrysobatrachus cupreonitens, exhibit inguinal amplexus (Laurent 1964), a phenom-enon observed elsewhere in Africa only among the aquatic Pipidae and in Nectophrynoides. In still another, Hyperolius obstetricans, parental care has been documented (Amiet 1974b). During the past three decades, considerable effort has been exerted toward elucidating the natural history and relationships of anuran groups in the Neotropics (for instance, see Duellman 1 970, 1 979); yet at the familial level, the treefrogs of Africa have remained largely untreated sys-tematically. A number of excellent regional fau-nal studies have included hyperoliids: Guibe and Lamotte on Mt. Nimba, Liberia (1958); Schiotz on Nigeria (1963); Perret on Cameroun (1960, 1966); Poynton (1964), Wager (1965), and Pass-more and Carruthers (1979) on South Africa; Stewart on Malawi (1967); Broadley on Zambia ( 1 97 1 ); and Guibe on Madagascar ( 1 978). To this list must be added the detailed, valuable reports resulting from explorations of the national parks in Zaire, formerly the Belgian Congo (de Witte 1941; Laurent 1950, 1972; Schmidt and Inger 1959). Of the various systematic revisions that have been published, among the most important are those of Laurent (1944) and Laurent and Com-baz ( 1950), which dealt with the thorny problems of the polytypic, hyperinclusive genera Megalix-alus and Hylambates. Hoffman revised the genus Kassina in 1942. More recently, Schiotz treated the Hyperolius viridiflavus complex (1971) and the Afrixalus of East Africa (1974); Laurent also treated the H. viridiflavus complex (1976), and Largen revised the genera Afrixalus {1974). Kas-sina (1975), and Leptopelis (1977) of Ethiopia. Perret (1958a & b, 1960) published studies of [1]
BioStor
