The Strongylocentrotus purpuratus genome contains a single ten-gene Hox complex >0.5 megabase in length. This complex was isolated on overlapping bacterial artificial chromosome and P1 artificial chromosome genomic recombinants by using probes for individual genes and by genomic walking. Echinoderm Hox genes of Paralog Groups (PG) 1 and 2 are reported. The cluster includes genes representing al...

Abstract Until now, the earliest fossil echinoderms have been predominantly known from early Cambrian of Laurentia and West Gondwana. Here, we describe Sprinkleoglobus extenuatus gen. et sp. nov. Chengjiang biota (Cambrian Series 2, Stage 3) Yunnan Province, China. The overall profile theca morphology ambulacra clearly establish it as an edrioasteroid echinoderm. This represents first discovery...

Echinoderms possess a skeleton with a unique and distinctive meshlike microstructure called stereom that is underpinned by a specific family of genes. Stereom is thus considered the major echinoderm synapomorphy and is recognized already in some Cambrian echinoderm clades. However, data on the skeletal microstructures of early echinoderms are still sparse and come only from isolated ossicles of...