Article: A new pipine frog from an Eocene crater lake in north-central Tanzania

The fossiliferous site of Mahenge, Tanzania, interpreted as a small lake that formed in a kimberlite intrusion, has yielded a vertebrate assemblage that includes scarce frog remains. Radiometric dating of the pipe indicates that the volcanic activity took place at 45.83 +/- 0.17 Ma, whereas infilling of the crater was completed in 0.2-1.0 myr after emplacement. The frogs, described herein, are preserved as partially articulated skeletons that represent a new pipine taxon, Singidella latecostata gen. et sp. nov. A parsimony analysis of fossil and extant pipoid frogs indicates that Singidella is more closely related to African Hymenochirus and Pseudhymenochirus than to South American Pipa. It also provides weak support for the sister-group relationship of Singidella and the bizarre Late Cretaceous Pachycentrata taqueti (replacement name for Pachybatrachus taqueti) from Niger, although the incomplete preservation of Pachycentrata precludes thorough comparisons. This record indicates that prior to the rifting in the Miocene the distribution of pipines extended into eastern Africa where they do not occur today.