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The Kihansi spray toad, Nectophrynoides asperginis, became extinct in the wild despite population monitoring and conservation management of its habitat in the Kihansi gorge, Tanzania. Previous investigations have indicated human induced habitat modification, predators, pesticides and disease as possible causes of a rapid population decline and the species extirpation. Here, we systematically investigate the role of disease in the extinction event of the wild toad population. The amphibian chytrid fungus, Batrachochytrium dendrobatidis, was detected in spray toads that died during the extinction event and subsequently in other amphibian species in Kihansi Gorge and the adjacent Udagaji Gorge, but not in any toads collected prior to this. Following the population decline, the remaining spray toad population gradually disappeared over a nine-month period. We demonstrate how demographic (rare, low fecundity, high elevation species) and behavioural (congregate in high densities) attributes predisposed the spray toads to chytridiomycosis, as a result of B. dendrobatidis infections, and how epidemic disease could have been exacerbated by altered environmental conditions in the spray wetlands. Our results show that chytridiomycosis was the proximate cause of extinction in the wild of N. asperginis. This represents the first known case of extinction by disease of an amphibian species in Africa. Captive breeding programs, in both the US and Tanzania, have been introduced in order to ensure the survival of the species and a reintroduction program is underway. However, we caution that chytridiomycosis remains an existing threat, which requires a comprehensive mitigation strategy before the desired conservation outcome of an established population of repatriated toads can be achieved. [ABSTRACT FROM AUTHOR]

The advertisement call, visual signalling, and tadpole of the recently described Phrynobatrachus ambanguluensis are described from the West Usambara Mountains, Tanzania. The call is a soft trill, similar but faster than the call of the sister species P. krefftii from the East Usambaras. Males have been observed flashing the bright yellow vocal sac without calling, which is the second reported non-vocal communication involving flashing the gular pouch in African frogs. The tadpole is generalised, identified by body shape and labial tooth row formula of 2(1)/4. [ABSTRACT FROM AUTHOR]

A new species of puddle frog in the genus Phrynobatrachus (Ranidae) is described from central Tanzania. It is compared to all other East African species and found to be most similar to P. natalensis. The distinctive features of this species include the male advertisement call, visible tympanum, snout-vent length, and the lack of digital discs. [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]