Edmontosaurus annectens, Marsh, 1892

Wosik, Mateusz, Goodwin, Mark B. & Evans, David C., 2019, Nestling-sized hadrosaurine cranial material from the Hell Creek Formation of northeastern Montana, USA, with an analysis of cranial ontogeny in Edmontosaurus annectens, PaleoBios 36, pp. 1-18 : 3

EDMONTOSAURUS cf. ANNECTENS MARSH, 1892

FIGS. 2–4

ReferredSpecimens —UCMP235860,nearly complete right dentary; UCMP 283755, incomplete and edentulous posterior portion of a right dentary dental battery; UCMP 235857, incomplete right surangular; UCMP 235859, incomplete right quadrate.

Formation/Age —Hell Creek Formation, latest Maas - trichtian.

Locality —Specimens were surface collected from the Sandstone Basin locality (UCMP locality V80092), Garfield County, northeastern Montana ( Fig. 1). Both dentaries (UCMP 235860 and UCMP 283755) were found near location No. 4 and the quadrate (UCMP 235859) near location No. 8 (see Supplemental Material Fig. SM1). Detailed locality information is on file at the UCMP. All permissions were obtained for land access, collecting, and curation of these fossils into the UCMP in 1983 and for an additional visit by UCMP field crews in 2016.

Remarks —The material described here was discov - ered and collected by J. H. Hutchison (UCMP 235860, 283755, 235859)and L. J.Bryant (UCMP 235857), 14 July 1983. Due to their taphonomic and preservational nature, each specimen is tentatively treated here as belonging to separate individuals. Relative size comparisons are discussed below.