A critical evaluation of the Resserops clade (Trilobita: Despujolsiidae, early Cambrian) with remarks on related redlichiacean families (Geyer, 2020).

Abstract

A characteristic group of redlichioid trilobites distributed in the late part of Cambrian Stage 3 and the early part of Cambrian Stage 4 in West Gondwana is revised and interpreted to constitute a monophyletic family Despujolsiidae. More than 25 species were previously assigned to the genera Perrector, Resserops, Eops, Marsaisia, Despojulsia, Pareops, Clariondia, Realaspis and Dolerolichia and are critically evaluated and revised herein, with Resserops regarded as an objective synonym of Perrector, and Pareops as being tentatively a synonym of Marsaisia. Species assigned to Resserops and Pseudoresserops reported from Jordan, the Siberian Platform and Mongolia are shown to belong to other clades. The species of Pararedlichia and the concept of the subfamily Pararedlichiinae and the family Abadiellidae, as well as relationships to and within the family Dolerolenidae are critically evaluated. The study includes data on relics of the digestive tract seen in specimens of Perrector falloti and P. brevilimbatus from strata of the Daguinaspis Zone of the western Anti-Atlas. They belong to the hitherto neglected Souss Fossil Lagerstaette and are the first published data on Cambrian trilobites with soft-part preservation from Africa. In addition, new taxa described from Morocco include Epicurella pustulata n. gen., n. sp., Marsaisia devoillei n. sp. and Marsaisia? lemdadensis n. sp. Moreover, Dolerolenus courtessolei Pillola, 1991 is regarded as representing a new genus, Boethiusia n. gen.