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A recently discovered fossil land tortoise (Testudines: Testudinidae) is described from the Pleistocene of Bermuda. Its morphology is sufficiently well preserved to allow assignment to the extinct North American genus Hesperotestudo . However, several features of this tortoise are unique and it is named Hesperotestudo bermudae sp. nov. A review of the phylogenetic relationships of the better known genera of the Testudinidae suggests that the affinities of Hesperotestudo lie with other North American tortoises ( Gopherus ) and not with Geochelone or other testudinines; thus, Hesperotestudo is reassigned to the Xerobatinae. This is at least the fifth documentation of a testudinid dispersing over open ocean to an oceanic island (the first for Hesperotestudo ) and it corroborates the hypothesis that members of this family are well suited to over-water dispersal.

We present phylogenetic analyses of both molecular and morphological data for the 23 major lineages of living turtles and seven key fossil taxa. Nearly 1 kilobase of cytochrome b sequence, 325 base pairs of 12S ribosomal DNA, and 115 morphological characters contained similar phylogenetic information, although each provided unique information on different nodes of chelonian history. A character-based combinability test (implemented in PAUP*) and a non- parametric test of taxonomic congruence indicated no strong evidence for heterogeneity among data sets, and we used a combined approach to estimate a final phylogeny of the major lineages of living turtles. This approach resulted in a very well-resolved tree, with only a few of the deep branches within the Cryptodira left as an unresolved polytomy. The addition of six relatively complete fossils chosen to help resolve this basal polytomy provided little added resolution to the tree and resulted in a sharp decline in bootstrap proportions for nodes near the fossils. Branch- length analysis and independent dates from the fossil record suggest that these unresolved nodes may represent a rapid radiation of the major cryptodiran lineages 90-120 million years ago. (Combined molecular and morphological data; fossil and recent phylogeny; mitochondrial DNA; starburst phylogeny; Testudines; total evidence.)

The described fossil testudinids from the Miocene of Africa are reviewed. Geochelone stromeri sp. nov. is described from Lower Pliocene (Langebaanweg) and Miocene (Namib) specimens. Kinixys erosa, an extant species, is reported from Songhor Hill. Chersina sp. is reported from Arrisdrift. Impregnochelys pachytectis gen. et sp. nov. is described from Rusinga Island, Kenya, and is unique in having the anterior shell opening orientated ventrally and in having struts on the internal surface of the neurals, but shares with Kinixys a unique epiplastron shape, a high number of axillary scutes and unique orientation of the head of the femur.