The oldest synallactid sea cucumber (Echinodermata: Holothuroidea: Aspidochirotida)

• DOI: 10.1007/s12542-010-0067-8
• Publication Date: 2010-07-05T11:30:41Z
• Authors: Mike Reich
• Keywords: Palaeontology; Earth Sciences; Paleontology; 14. Life underwater; 551; 01 natural sciences; Echinodermata; Holothuroidea; Ordovician; Sweden; Baltic Sea; Echinodermata; Holothuroidea; Ordovizium; Schweden; Ostsee; 0105 earth and related environmental sciences

Aspidochirote holothurian ossicles were discovered in Upper Ordovician-aged Öjlemyr cherts from Gotland, Sweden. The well-preserved material allows definitive assignment to the family Synallactidae, a deep-sea sea cucumber group that is distributed worldwide today. The new taxon Tribrachiodemas ordovicicus gen. et sp. nov. is described, representing the oldest member of the Aspidochirotida. The further fossil record of Synallactidae and evolutionary implications are also discussed.