Tommotiids from the early Cambrian (Series 2, stage 3) of Morocco and the evolution of the tannuolinid scleritome and setigerous shell structures in stem group brachiopods.
2014 (English)In: Palaeontology, ISSN 0031-0239, E-ISSN 1475-4983, Vol. 57, no 1, 171-192 p.Article in journal (Refereed) Published
An assemblage of tannuolinid sclerites isdescribed from the Amouslek Formation (Souss Basin) of theAnti-Atlas Mountains in Morocco. The assemblage containstwo species, Tannuolina maroccana n. sp., which is representedby a small number of mitral and sellate sclerites, andMicrina sp., represented by a single mitral sclerite. Tannuolinamaroccana differs from other species of the genus in thepresence of both bilaterally symmetrical and strongly asymmetricalsellate sclerites. This observation suggests that thescleritome of Tannuolina was more complex than previouslythought and that this tommotiid may have held a more basalposition in the brachiopod stem group than previouslyassumed. The shell structure of both T. maroccana andMicrina sp. is well preserved and exhibits two fundamentallydifferent sets of tubular structures, only one of which waslikely to contain shell-penetrating setae. Based on these observations,the structure of the tannuolinid shell is discussed andits implications for the evolution of tubular microstructuresin stem and crown group brachiopods are analysed.
Place, publisher, year, edition, pages
2014. Vol. 57, no 1, 171-192 p.
Research subject Ecosystems and species history
IdentifiersURN: urn:nbn:se:nrm:diva-861DOI: 10.1111/pala.12060OAI: oai:DiVA.org:nrm-861DiVA: diva2:764553
ProjectsOrigin and early evolution of major animal clades in the Cambrian Period