Note on the gut preserved in the Lower Cambrian Lingulellotreta (Lingulata, Brachiopoda) from southern China

Abstract

Lingulellotreta malongensis Rong is the earliest known taxon of the family Lingulellotretidae, which is characterized by the presence of a pedicle foramen as well as an internal pedicle tube. New material from the Early Cambrian Chengjiang Lagerstätte of southern China provides improved anatomical knowledge for lingulellotretid species especially for the digestive system. Additional gut fossils exhibit distinctly the anterior portion composed of esophagus and distended stomach, situated in the alleged visceral cavity, with the recurved intestine accommodated inside a hollow pseudointerarea. The frequency of occurrence of this intestinal layout suggests that this is not just an artefact of preservation. The gross configuration of the guts and the way they are preserved in the fossils suggest that they are in situ and, therefore, we can assume that Lingulellotreta had a hollow cavity presumably subtended by the pseuodelthyrium, which was invaded and occupied by the visceral organs. Hence, these fossils demonstrate the dangers of extrapolating crown-group soft-tissue configuration to the stem group. © 2007 The Authors.