caa a22 4500 388093463 CHVBK 20180307125258.0 cr unu---uuuuu 161130e199904 xx s 000 0 eng 10.4039/Ent131171-2 doi S0008347X00009780 pii (NATIONALLICENCE)cambridge-10.4039/Ent131171-2 NEW AMBER DEPOSIT PROVIDES EVIDENCE OF EARLY PALEOGENE EXTINCTIONS, PALEOCLIMATES, AND PAST DISTRIBUTIONS [Elektronische Daten] A large, previously unstudied amber deposit in British Columbia dating from the Early to Middle Eocene (50−55 Ma) provides a noteworthy new source of terrestrial invertebrates and other life forms. This deposit contains what are likely the earliest unequivocal ants (members of the family Formicidae), including extinct representatives of Technomyrmex Mayr 1872, Leptothorax Mayr 1855, and Dolichoderus Lund 1831. Discovering Technomyrmex and a corydiinid cockroach, both of which are currently restricted to tropical regions, confirms earlier evidence of warm paleoclimates and past biogeographic distributions in the early Paleogene. Chemical analysis of the amber indicates that the source tree was an araucarian belonging to or near the genus Agathis Salisbury 1807, and demonstrates that this genus survived into the Tertiary in the Northern Hemisphere, since previous records revealed Agathis as a component only of the Cretaceous forests in North America. Comparing the Hat Creek fossil assemblages in this deposit with those from the well-studied western Canadian Late Cretaceous amber deposits offers a unique opportunity to study extinction and speciation events on both sides of the Cretaceous-Tertiary boundary. Copyright © Entomological Society of Canada 1999 Poinar George Department of Entomology, Oregon State University, Corvallis, Oregon, USA 97331 Archibald Bruce Department of Biological Sciences, Simon Fraser University, Burnaby, British Colombia, Canada V5A 1S6 Brown Alex 629 Euclid Avenue, Berkeley, California, USA 94708 The Canadian Entomologist Cambridge University Press 131/2(1999-04), 171-177 0008-347X 131:2<171 1999 131 TCE https://doi.org/10.4039/Ent131171-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.4039/Ent131171-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Poinar George Department of Entomology, Oregon State University, Corvallis, Oregon, USA 97331 NATIONALLICENCE 700 1- Archibald Bruce Department of Biological Sciences, Simon Fraser University, Burnaby, British Colombia, Canada V5A 1S6 NATIONALLICENCE 700 1- Brown Alex 629 Euclid Avenue, Berkeley, California, USA 94708 NATIONALLICENCE 773 0- The Canadian Entomologist Cambridge University Press 131/2(1999-04), 171-177 0008-347X 131:2<171 1999 131 TCE CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge