Article
Article
Irregularia
Article By:
Mooi, Rich Department of Invertebrate Zoology and Geology, California Academy of Sciences, San Francisco, California.
Last reviewed:2012
DOI:https://doi.org/10.1036/1097-8542.353700
The name given by P. A. Latreille in 1825 to what is now recognized as a natural (monophyletic, that is, evolved from a common ancestral form) group of echinoids (sea urchins). Previously, workers such as J. Durham and R. Melville suggested that the group was polyphyletic (evolved from different ancestral lineages), a proposal followed by other influential works. However, this suggestion has been rejected by more recent workers such as M. Jensen, A. Smith, and T. Saucède and colleagues who showed in phylogenetic analyses that all irregular echinoids are derived from eodiadematid-like forms in the Lower Jurassic.
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