Fossil History

The first fossil Collembola occur in the 400 million-years-old Rhyme chert deposits of the Devonian, although there are secondary fossil hints of earlier Collembola occurrence. These fossils display very modern collembolan features, including typical entognathous, chewing mandibles; ventral tube; and, probably, a furcula. The single described species— Rhyniella praecursor—has been placed in a variety of families, including recently Isotomidae; however, all family placement must be considered very tentative and it is likely that one or two additional species are in this deposit. A single specimen of a very probable member of the family Entomobryidae was found in Permian shale of South Africa but extensive collembolan fossils are limited to amber of the Cretaceous, Oligocene, Miocene, and Pliocene. Collembola represent only a small fraction of the hexapods found in amber, and they are absent from many amber deposits; however, there are over 70 specimens from late Cretaceous Canadian amber, over 160 from the Baltic Eocene amber, about 130 from Miocene amber of Chiapas and the Dominican Republic, and 16 from Pliocene Japanese amber. The Cretaceous material has no identifiable specimens of extant genera and most specimens can be placed in one of eight extinct genera. All the remaining amber specimens can be placed in extant genera and in a few cases in extant species. Since the Eocene, generic extinction appears to have been absent, a unique feature among hexapods well represented in Eocene deposits.

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