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Speciation by polyploidization has been documented to have independently occurred in 12 families of anuran amphibians. Tomopterna tandyi was described as a South African allotetraploid species of sand frogs in the family Pyxicephalidae. Recent taxonomic revisions and new species descriptions in the genus present problems with respect to the evolution of this tetraploid species. Chromosomes, mitochondrial and nuclear gene sequences, isozymes, and male mating calls were examined for T. tandyi and for diploid species of Tomopterna. Mitochondrial sequences confirmed the diploid species, T. adiastola, to be the maternal ancestor that gave rise to the tetraploid about 5 mya. Nuclear sequences and isozymes reveal a complex reticulation of paternal ancestry that may be explained by occasional hybridization of T. tandyi with diploid species of Tompoterna at various times in sympatric populations. Interspecific diploid to tetraploid gene introgression is suspected to have also occurred in Australian and North American tetraploid species of frogs. Diploid to tetraploid introgression is facilitated through triploid hybrids that are more viable than diploid hybrids and produce unreduced triploid eggs. Key words: polyploid frogs, Tomopterna tandyi, chromosomes, gene sequences, isozymes, acoustics Il a ete documente que la speciation par le biais de la polyploidisation serait survenue independamment chez 12 familles d'amphibiens anoures. Le Tomopterna tandyi est une espece sud-africaine allotetraploide au sein de la famille des Pyxicephalidae. Les recentes revisions taxonomiques et les nouvelles descriptions d'especes au sein du genre presentent des problemes quant a l'evolution de cette espece tetraploide. Les auteurs ont examine les chromosomes, des sequences geniques mitochon-driales et nucleaires, des isoenzymes et les cris sexuels des males chez le T. tandyi et les especes diploides de Tomopterna. Les sequences mitochondriales ont confirme que l'especes diploide T. adiastola serait l'ancetre maternel et aurait donne naissance au tetraploide il y a environ 5 millions d'annees. Les sequences nucleaires et les isoenzymes ont revele une reticulation complexe du cote de l'ancetre paternel, laquelle pourrait s'expliquer par des hybridations occasionnelles entre le T. tandyi et les especes diploides de Tomopterna a diferents moments au sein de populations sympatriques. Une telle introgression genique entre diploide interspecifique et tetraploide est egalement soupconnee chez des especes tetraploides de grenouilles australiennes et nord-americaines. L'introgression diploide vers tetraploide est facilitee par des hybrides triploides qui sont plus viables que les hybrides diploides et ils produisent des ovules non-reduits triploides. [Traduit par la Redaction] Mots-cles : grenouilles polyploides, Tomopterna tandyi, chromosomes, sequences geniques, isoenzymes, acoustique, Introduction African sand frogs in the genus Tomopterna are robust burrowing frogs that favour sandy habitats and are widespread in drier sub-Saharan habitats. Eighteen species are recognized (Channing and Rodel [...]

Despite a relatively broad distribution in Africa, the Spotted Rubber Frog, Phrynomantis affinis, is extremely rarely encountered. Only 18 specimens from 12 localities have been collected with a few additional observations recorded. Virtually nothing of the species' natural history is known. We report or summarise new localities and range extensions of P. affinis in Namibia and Zambia and describe the call for the first time. We also compare its call to that of the sister species, P. bifasciatus, describing this call for the first time and noting a considerable range extension. The calls show several key differences, with P. affinis calls generally having a lower dominant frequency, pulse repetition rate, and number of pulses than P. bifasciatus. The calls of Namibian and Zambian P. affinis also show marked differences. These descriptions add valuable natural history information for both species and will considerably improve the field detection of the enigmatic P. affinis. [ABSTRACT FROM AUTHOR]

Four species of African bullfrogs are currently recognised. We describe a new species from southern Africa, which can be distinguished on the basis of morphology, advertisement call and DNA sequences. Morphologically it differs from other bullfrogs by a combination of characteristics including a tympanum that is smaller or equal in size to the eye, and smaller in diameter than the space between eye and tympanum, presence of a white dot on the tympanum, longitudinal skin ridges with speckling between dorsal mottles, pale vertebral line usually present, absence of cream coloured lateral stripes, absence of a pale interorbital-bar, upper jaw-barring absent or faint. It has been confirmed from north-eastern Namibia, southern Angola and north-western Botswana. Three further undescribed species are recognised but not formally named, pending further investigation. We confirm the genetic distinctiveness of P. angusticeps. [ABSTRACT FROM AUTHOR]

We use mitochondrial and nuclear gene sequences and morphology to re-evaluate the taxonomy of Bufo vertebralis grindleyi Poynton, 1963, currently a junior synonym of Poyntonophrynus fenoulheti (Hewitt & Methuen, 1912); and morphology and advertisement calls to re-evaluate the status of Bufo jordani Parker, 1936, currently a junior synonym of Poyntonophrynus hoeschi (Ahl, 1934). According to our results including comparisons to other congeners, we elevate both taxa to full species as Poyntonophrynus grindleyi (Poynton, 1963) and Poyntonophrynus jordani (Parker, 1936). Our new P. grindleyi record is the first record of the species for Mozambique. [ABSTRACT FROM AUTHOR]

Records of biodiversity over time are important resources for assessing conservation priorities. However, such baseline data are missing for regions of key biodiversity importance. The Eastern Arc Mountains of Tanzania are known for their species richness and endemism, but not all mountain blocks have received the same attention. The Ukaguru Mountains, for example, have only infrequently been surveyed by herpetologists, with the first known herpetological survey in 1990. Here we compile and quantify all amphibian survey efforts in the Ukaguru Mountains in the past 30 years, publish an updated species list and comment on the health of amphibian populations and their habitat. We report on fourteen described species of amphibians, with potentially three additional species awaiting formal description. Of these seventeen lineages, seven are endemic to the Ukaguru Mountains. Although total species numbers remain low, compared with other Eastern Arc Mountains, surveys frequently recorded new species for the Ukaguru Mountains and for science. Worryingly, however, endemics, such as the monotypic bufonid Churamiti maridadi, have not been recorded in the past fifteen years. Our analyses show the region is becoming warmer and drier and is experiencing an alarming rate of deforestation. We find that over the past 30 years, dense forest cover inside the boundaries of the forest reserves has reduced by 8.4%. [ABSTRACT FROM AUTHOR]

The frog Arthroleptides dutoiti Loveridge, 1935, endemic to Mount Elgon, East Africa was last collected in 1962 and has not been observed since. The species is regarded as Critically Endangered by the IUCN Red List and is a priority species on the Zoological Society of London's EDGE (Evolutionarily Distinct, Globally Endangered) project, given its Red List status and phylogenetic distinctiveness. We analyse temporal patterns of abundance (1934–2014) of A. dutoiti and the remainder of the Mount Elgon amphibian assemblage to infer the probability of re-encountering A. dutoiti and assess whether declines are species specific to A. dutoiti, or whether they are assemblage-wide phenomena. Our results show that for localities where surveys have been repeatedly conducted, A. dutoiti is likely to be locally extinct. Declines are observed in other Mount Elgon amphibians, encompassing both specialists and generalists. Causal factors for declines are unknown, but habitat change might be important, given the high degree of forest loss in the area, especially since the turn of the 20th century. Urgent sampling of preferred microhabitats of A. dutoiti at the type locality and surrounding areas beyond those included in our study are required to determine whether or not the species is extinct. Impacts on other taxonomic groups would also be useful to understand so that it can be determined how broad the changes are for the Mount Elgon biota. [ABSTRACT FROM AUTHOR]

Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species' population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate 'intactness scores': the remaining proportion of an 'intact' reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region's major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems., (© 2024. The Author(s).)

Tomopterna pulchra (Boulenger, 1896) was described from Lake Tanganyika based on a single specimen. It was synonymised with Tomopterna tuberculosa (Boulenger, 1882) by Loveridge (1957) who noted that it did not fully agree with the description of T. tuberculosa, especially in the difference in dorsal colouration. Genetic differences show that two species are confused, although their advertisement calls and morphology are similar, except for the presence of a pale vertebral stripe mostly in eastern populations. We consider the advertisement calls, morphology, and genetic differences, and remove Tomopterna pulchra (Boulenger, 1896) from the synonymy of Tomopterna tuberculosa. Divergence dating shows that these two species separated in the mid-Miocene. Tomopterna pulchra breeds in rocky habitats, whereas T. tuberculosa breeds in sandy areas, typical of the genus. Based on genetically confirmed specimens, presently T. tuberculosa is known in the west (Angola and Namibia) while T. pulchra is only known from the east (Zambia and Tanzania). The examination of specimens for the presence or absence of a vertebral stripe infers that these species are widespread. Further work is required to determine if the two species are sympatric, and the extent of their ranges.

African reed frogs are widespread and highly polymorphic for colour pattern. The Hyperolius viridiflavus complex includes 121 described taxa, including subspecies, which are presently synonymised as 16 species. However, the taxonomy is confused as colour patterns have been used to identify species, despite an inadequate understanding of pattern variation and overlap. This study examined 267 sequences of the 16S rRNA fragment from individuals across the range of the group, from Senegal to Ethiopia, and to the southern tip of Africa. Maximum likelihood analysis showed that there were 14 species that only partially agreed with existing taxonomy. This study recognised the following species: Hyperolius viridiflavus, H. marmoratus, H. marginatus, H. parallelus, H. nitidulus, H. glandicolor, H. tuberculatus, H. mariae, H. noblei, H. goetzei, H. spatzi, H. bangwae, H. dintelmanni and an undescribed species from southern Cameroon. Hyperolius swynnertoni was found to be embedded within H. marmoratus, H. hutsebauti was embedded within H. parallelus, H. rhodesianus and H. pyrrhodictyon were embedded within H. marginatus and H. sheldricki was embedded within H. glandicolor. There was no sequence information to determine the status of Hyperolius nimbae. The ranges of the species are presented, although these are expected to change as more sequences become available. The use of DNA sequences to identify animals is recommended in this group, as the variation in advertisement calls and morphology is not well understood.