Where: Alaska (61.7° N, 149.1° W: paleocoordinates 68.0° N, 125.0° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Chickaloon Formation, Thanetian to Thanetian (59.2 - 47.8 Ma)

• Premier coal group. The Chickaloon Formation is exposed there and elsewhere throughout the east-west trending Matanuska Valley in south-central Alaska and overall comprises a ~1500 m thick sequence predominantly made up of sandstones, mudrocks, and coals of Late Paleocene/Early Eocene age (Flores and Stricker, 1993; Trop et al., 2003; Neff et al., 2011). Zircon fission track and K/Ar dates on ash partings in the upper Chickaloon Formation at the collection site provide age constraint, placing the Paleocene-Eocene boundary within the Chickaloon’s Premier Coal Zone (Triplehorn et al., 1984; Flores and Stricker, 1993) (fig. 2). The overlying Early Eocene Jonesville coal zone in the Chickaloon is in conformable contact with Eocene-age Wishbone Formation conglomerates exposed at the top of Wishbone Hill (Trop et al., 2003; Neff et al., 2011).

• group of beds-level stratigraphic resolution

Environment/lithology: fluvial-lacustrine; lithified siliciclastic sediments

Size class: macrofossils

Collected by J. Wolfe, Hopkins in 1962; reposited in the USNM

Primary reference: R. Garrouste and A. Nel. 2019. Alaskan Palaeogene insects: a challenge for a better knowledge of the Beringian 'route' (Odonata: Aeshnidae, Dysagrionidae). Journal of Systematic Palaeontology 17:1939-1946 [M. Clapham/M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 204785: authorized by Matthew Clapham, entered by Matthew Clapham on 23.09.2019

Creative Commons license: CC BY (attribution)