DISCOVERY OF A NEW SERENGETI TREEFROG

Robert C. Drewes, PhD
Curator & Chairman
Department of Herpetology
California Academy of Sciences

 

 Abstracted from R. C. Drewes. 1997. A new species of treefrog from the Serengeti National Park, Tanzania (Anura: Hyperoliidae: Hyperolius) Proc. Calif. Acad. Sci. 49(13):439-446. All photos done by the Author.

 

Serengeti National Park in northwestern Tanzania is justly famous for its concentrations of plains game. Thousands of tourists travel to Tanzania each year to view vast herds of wildebeest, zebra and topi along with populations of major carnivores.

 

Due to hard, underlying volcanic lava and ash which is impenetrable to the roots of most tree species, the Serengeti is like a great sea of grassland interspersed with "islands" of rock called kopjes. These are all well-known landmarks and bear names such as Barafu (ice) Kopjes, Gol Kopjes, Maasai Kopjes, etc.

 

 

 

Prior to 1951, when the Serengeti was gazetted as a national park, its vast plains were part of the grazing lands of the Maasai. These colorful herdsmen still inhabit the periphery of the Serengeti, including Ngorongoro Crater.

 

 

 

 

In July, 1992, during an Academy photographic tour to East Africa, the group stopped for lunch at Moru Kopjes, at the southern end of the Serengeti.

Moru Kopjes are the site of the famous Gong Rock This resonant, lemon wedge-shaped rock makes a deep sound when struck and was used in the old days by Maasai to summon tribal members for ceremonies.

 

One of the youngest members of the group, Christopher Burnette (wearing blue in photo at left) noticed a tiny, rough-skinned cryptic treefrog, resting in one of the depressions on the north face of the Gong itself. He called the group leader, and Dr. Drewes immediately recognized the frog as an undescribed species of the genus Hyperolius. Drewes had never seen toad-like skin such as this on any other member of the genus.

 

Drewes and some of his colleagues sought and received permission from the Tanzanian authorities to return to the Serengeti during the rains of 1993.

There they found some more specimens wedged in cracks around Moru Kopje, and yet another actually on the Gong itself (left, above). After several years of comparisons with museum material of other Hyperolius from different parts of Africa, the new species was described:


 Hyperolius orkarkarri

 Drewes named the species in honor of the Maasai, who gave up their grazing lands so that the Serengeti could be established as one of the most famous national parks in the world. Orkarkarr is the Maa word for gong.

The Serengeti is probably the most intensively studied ecosystem in all of Africa. The overlooked existence of Hyperolius orkarkarri reflects the fact that for years the great majority of effort, support and funding for species-level biological work has been applied toward ecological and behavioral studies, and these are usually of mega-vertebrates such as bovids, carnivores and primates. Meanwhile, the arthropod and smaller vertebrate faunas have been almost totally neglected, and while these are just as ecologically important (if not more so) as the large mammal and bird faunas, they remain very poorly understood. There is a profound misunderstanding that these habitats and their species are already fully documented and well-understood. This is far from the case. In truth, the behavior and ecology of the Serengeti megafauna is available for study only because these conspicuous species have already been described by systematists and their evolutionary relationships clarified to some degree.

It is true that as awareness of environmental problems has grown on a world-wide scale, African governments have begun to pay more attention to habitat issues, especially those that directly affect economies and attract significant monies from non-governmental organizations. There has been much global media attention to "vanishing habitats," and perhaps as a result, we are beginning to meet African students who see careers in biology as viable options. Most unfortunately, opportunities to train in systematic biology, the foundation for all other biological disciplines, are almost nonexistent, and most of the students we know have trained in ecology or ethology. Like the rest of the world, Africa needs more systematists.