MOVING UP THE RANKS NEW AFRICAN BULLFROG FINALLY DESCRIBED
New bullfrog. Credit: Louis du Preez
F or over a century, a massive bullfrog has evaded detection. This comes as no surprise due to the remoteness of the Nyae Nyae-Khaudum landscape on the Namibia-Botswana border. When researchers finally discovered it, it did not match Africa’s existing bullfrog species, leading to further work and the description of a brand new species.
bullfrog to warrant classification as a new species, but we needed more specimens and tissue to be collected for a molecular study to confirm our suspicions,” explained prof Louis Du Preez of North-West University in South Africa. He led the team that collected and studied the new bullfrog. He works in the department of Environmental Sciences and Management, under the African Amphibian Conservation Research Group. This was only the start. Then, another opportunity arrived in 2021. Dr Francois Jacobs from the Ministry of Fisheries and Marine Resources (MFMR) invited Du Preez to a frog and reptile survey in the Khaudum-Nyae Nyae ecosystem as part of a larger collaborative project between Dr Ed Netherlands from Free-State University, MFMR, MEFT, Dr Francois Becker and his team from the National Museum of Namibia, and the Kwando Carnivore Project. Beytell’s son, Piet also participated in the expedition. The bullfrogs found in the Namibian pans were identical to the specimen previously found in Botswana’s Okavango Delta. While closely matching that lone sample, the analysis showed these bullfrogs differed significantly from all other African bullfrogs. They could provide conclusive molecular proof that this bullfrog represented an entirely new species.
“At the moment, we do not think it is threatened. It occurs in a very wide area, it is just a remote area. That is why it is not discovered before,” said Du Preez. The Nyae Nyae-Khaudum pans, where they found the bullfrog, were officially declared Namibia’s sixth Wetland of International Importance under the Ramsar Convention in February 2024, which could lead to further scientific expeditions and research. The bullfrog, measuring 210mm, is the largest specimen of bullfrogs. They prey on birds, small mammals, and frogs. Males also battle it out in powerful and sometimes deadly wrestling matches for mating rights. The species occurs in parts of northeastern Namibia, southern Angola, southwestern Zambia, and northwestern Botswana.
100 YEARS The bullfrog is the largest frog discovered in over 100 years
210MM The length of the largest individual
FOUR The number of bullfrog species currently in Southern Africa
Credit: Louis du Preez
The newly described Beytell’s bullfrog highlights the ecological importance of the region, something that the late conservation leader Ben Beytell recognised. As former director of Parks and Wildlife in the Ministry of Environment and Tourism (MFET) in Namibia, he motivated the area’s protection, first as a game reserve in 1989 and then as Khaudum National Park in 2008. Fittingly, the newly described bullfrog was named Beytell’s bullfrog ( Pyxicephalus beytelli ) in his honour. “I was intrigued when one of my former students, Marleen le Roux (now Marleen Byron), showed me a bullfrog specimen she had collected from the Okavango Delta in 2010. It looked different enough from the existing three species of African
173 The amount of frog species in Southern Africa
Credit: Louis du Preez
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