First records from Laurentia of some middle Cambrian (Series 3) sponge spicules

Peel, J.S., February 2017. First records from Laurentia of some middle Cambrian (Series 3) sponge spicules. Alcheringa 41, 000–000. ISSN 0311-5518.

Spicules of the sponges Silicunculus Bengtson, Australispongia Dong & Knoll and Thoracospongia Mehl are described from the middle Cambrian (Cambrian Series 3) of North Greenland. The occurrences document the first records from the Cambrian of Laurentia of spicules initially reported from Australia. Obese spicules of Thoracospongia are now known to occur in strata of Cambrian Series 2 (Stage 4, Botoman) to Cambrian Series 3 (Stage 5 and Drumian) age in Australia, northern and southeastern Siberia and in the uppermost Henson Gletscher Formation (Cambrian Series 3, Stage 5) of western Peary Land. Morphologically similar obese spicules from the USA, Jordan, Iran and Sweden suggest an evolutionary trend towards armouring of the outer sponge surface during the middle and late Cambrian. New species described are Silicunculus saaqqutit sp. nov., Thoracospongia lacrimiformis sp. nov.

John S. Peel [john.peel@pal.uu.se], Department of Earth Sciences (Palaeobiology), Uppsala University, Villavägen 16, SE-752 36 Uppsala, Sweden. Received 3.7.2016; revised 13.9.2016; accepted 15.9.2016.