Exceptionally-preserved Mickwitzia from the Indian Springs Lagerstätte.
(English)In: Journal of Paleontology, ISSN 0022-3360, E-ISSN 1937-2337Article in journal (Other academic) Accepted
A new assemblage of the early Cambrian stem group brachiopod Mickwitzia is described from the Indian Springs Lagerstätte possessing exceptionally preserved mantle setae. Critical analysis of shell structure and mantle setae from these specimens with those from additional sites with variable diagenetic history reveals the extent of taphonomic alteration and further sheds light on the phylogenetic position of the mickwitziids. A morphometric approach to shell outline and growth landmarks within these specimens reveals a clear species level discriminant signal of Nevada Mickwitzia in comparison to M. monlifera from Sweden. Detailed electron micrographs allow revision of the genus diagnosis for Mickwitzia based on presence of inward pointing phosphatic cones and tangential setae bearing tubes. We also conclude the inward pointing cone structures are not consistent with setal bearing structures as previously thought, but rather represent an endopunctae-like structure. A tommotiid-like shell architecture and presence of acrotretid columns in the dorsal juvenile shell of M. cf. occidens further strengthens the proposed close relationship between stem-group brachiopods and tommotiids.
Brachiopoda, Mickwitzia, shell penetrating setae, lower Cambrian, Indian Springs
Other Earth and Related Environmental Sciences Geology Evolutionary Biology
Research subject Earth Science with specialization in Historical Geology and Palaeontology
IdentifiersURN: urn:nbn:se:uu:diva-216149OAI: oai:DiVA.org:uu-216149DiVA: diva2:689545
FunderSwedish Research Council, 2009-4395, 2012-1658