GSA Annual Meeting in Indianapolis, Indiana, USA - 2018

Paper No. 259-12
Presentation Time: 9:00 AM-6:30 PM

A NEW EARWIG (DERMAPTERA) FROM EARLY MIOCENE DOMINICAN AMBER


MAI, Bohao1, THOMAS, M. Jared2, HEADS, Sam2 and CHRISTIE, Max3, (1)Department of Geology, The University of Illinois, Urbana, Illinois, 401 E Chalmers st, apt 309, Champaign, IL 61820, (2)Illinois Natural History Survey, University of Illinois at Urbana-Champaign, Forbes Building, 1816 S. Oak Street, MC-652, Champaign, IL 61820, (3)Department of Geology, University of Illinois, Urbana, IL 61801

A new genus and species of earwig is discovered and described from Early Miocene Dominican amber approximately 20 to 16 Ma ago (Burdigalian) from the La Toca Formation in the Santiago region of the Dominican Republic. Among the fossils yielded from the Dominican amber, this specimen is the first from the order Dermaptera to be formally described.

The specimen was studied using macro-photography, microscopy, photomicrography, and specimen illustration. Through comparative morphological study, the fossil has been assigned to the suborder of Neodermaptera by its apomorphic trait of the three-segmented tarsi (trimerous) and the absence of ocelli. While assignment to specific family awaits further study, the specimen can still be excluded from the Eudermaptera based on the lack of modification of the second tarsomere (extreme elongation/dilation beneath the third tarsomere). The epizoic families of Hemimeridae and Arixeniidae are also excluded based on the lack of epizoic adaptive traits.

As Earwigs are scarce in the insect fossil record, our current understanding of the evolutionary history of Dermaptera is lacking. Hence, this study is significant in contributing new evidence for a better understanding of dermapteran evolution. In addition, this is also the first dermapteran to be described from Dominican amber. Therefore, the results of this study also contributes to understanding the origins of the modern Caribbean dermapteran fauna as well as a more complete picture of the regional ecosystem during the Early Miocene.