Echinoids from the Triassic (St. Cassian) of Italy, Their Lantern Supports, and a Revised Phylogeny of Triassic Echinoids

Abstract

Three new species of Triassic echinoids are described from the St. Cassian (Karnian) beds of Cortina d'Ampezzo, Italy: Levicidaris furlani, L. pfaifferi, and Zardinechinus giulinii. Hundreds of echinoid fragments from the same beds show that 16 species lack apophyses (interambulacral lantern supports) and 7 possess them. Previously, paleontologists assumed that most Triassic echinoids had apophyses. Their absence from so many species and the presence of slightly developed auricles (ambulacral lantern supports) suggest that two echinoid lineages crossed from the Paleozoic to the Triassic: one, possessing apophyses, is ancestral to all modern cidaroids; a second, lacking apophyses, gave rise to all noncidaroid echinoids.