Bradyfallotaspis coriae, Gapp, Wesley, Lieberman, Bruce S., Pope, Michael C. & Dilliard, Kelly A., 2011

Gapp, Wesley, Lieberman, Bruce S., Pope, Michael C. & Dilliard, Kelly A., 2011, New olenelline trilobites from the Northwest Territories, Canada, and the phylogenetic placement of Judomia absita Fritz, 1973, Zootaxa 2918, pp. 15-28 : 17-19

Bradyfallotaspis coriae n. sp.

(Fig. 3.1–3.6)

Type material. Holotype PWNHC-2009.20.1. Paratypes KUMIP 320696-320700 and PWNHC-2009.20.2- 2009.20.8 from Nevadella zone, Early Cambrian, Sekwi Formation, Mackenzie Mountains, Northwest Territories, Canada (Section 2, 345– 375 m above base of formation and in float; Section 14 in float). There are a total of 13 specimens.

Etymology. Named in honor of Corinne Myers, University of Kansas, for her assistance with laboratory techniques that facilitated the completion of this research.

Diagnosis. Anterior cephalic border (sag.) equal to length (sag.) of LO; preglabellar area present; ocular ridges connected to glabella at L3; ocular lobes in contact with posterior border furrow; LO spine present in some specimens.

Description. Width of cephalon (tr.) is greater than or equal to twice the cephalic length (sag.); anterior cephalic border length (sag.) is approximately equal to or slightly less than the length (sag.) of LO; preglabellar field is present; width (tr.) of the extraocular area is approximately 1.5 times the width (tr.) of the interocular area; a strongly incised SO is present (when preservation allows determination); a small spine or node is present on the posterior margin of LO in some specimens.

Discussion. This species can be distinguished from B. sekwiensis by its relatively narrower (sag.) anterior cephalic border and by its possession of a preglabellar area. It differs from B. patula , B. nicolascagei , and B. sekwiensis by possession of ocular lobes in contact with the posterior border furrow. Several specimens (Fig 3.3 and 3.6) are smaller and relatively narrower than typical specimens of B. coriae , yet they possess key diagnostic features such as ocular lobes that contact the posterior border furrow, a preglabellar field, and ocular ridges connecting the ocular lobes at the posterior lateral margin of LA (although not as prominently as in larger specimens). These may be earlier ontogenetic forms of B. coriae and are treated as such in this paper.