Reappraisal of the holotype of “testudo” costarricensis, a tortoise supposedly from the oligocene or lower miocene of Costa Rica

[摘要] “Testudo” costarricensis was described as a basal tortoise from the Oligocene or lower Miocene of Costa Rica and considered as evidence of a migration of tortoises from North America to South America to provide an ancestor to the modern genus Chelonoides. However, this was based on an incorrect reconstruction of the holotype carapace and plastron of continental T. costarricensis, which, when corrected, is identical to the North American Oligocene tortoise Oligopherus laticunea. Furthermore, there are no continental sedimentary rocks of Oligocene to Miocene age at the purported type locality nor does the matrix associated with the holotype of T. costarricensis match any sediment found there. T. costarricensis thus, apparently, is not a tortoise from the continental Miocene of Costa Rica. Instead, it was likely based on a specimen of Oligopherus laticunea from the United States.

[学科分类] 地质学