Where: Alaska (62.0° N, 147.3° W: paleocoordinates 28.3° N, 80.4° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Emileia sauzei ammonoid zone, upper siltstone Member (Tuxedni Formation), Early/Lower Bajocian (171.6 - 168.4 Ma)

• The ichthyosaur was found in the lower portion of the unnamed upper siltstone unit of the Tuxedni Formation (Imlay, 1964).

•The age of the UAMES 3411 is well constrained on the basis of a rich ammonite fauna associated with the specimen. Ammonoids collected from the discovery site in the course of this study are referred to several taxa also recognized by Imlay (1964) from the same locale (USGS Mesozoic locality 24113; Imlay, 1961, 1964). Notable members of this assemblage include Parabigotites crassicostatus Imlay, 1961, Stephanoceras obesum Imlay, 1964, Witchellia adnata Imlay, 1964, Bradfordia costidensa Imlay, 1964, and Otoites cf. O. pauper Westermann, 1954 (for a comprehensive list, see Imlay, 1964). Collectively, Imlay (1964) considered this assemblage equivalent to the European Emileia (formerly Otoites) sauzei Zone, equivalent to the northern Sonninia propinquans Zone (Gradstein, Ogg & Smith, 2004), which is currently recognized as middle Early Bajocian in age (Gradstein et al. 2012)

Environment/lithology: marine; siltstone

Size class: macrofossils

Collection methods: surface (in situ), mechanical,

• UAMES, University of Alaska Museum, Fairbanks

•discovered by an amateur palaeontologist

Primary reference: P. S. Druckenmiller and E. E. Maxwell. 2013. A Middle Jurassic (Bajocian) ophthalmosaurid (Reptilia, Ichthyosauria) from the Tuxedni Formation, Alaska and the early diversification of the clade. Geological Magazine [R. Benson/R. Benson]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 142116: authorized by Roger Benson, entered by Roger Benson on 05.04.2013

Creative Commons license: CC BY (attribution)