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A revision of Palaeacmaea (Upper Cambrian) (?Cnidaria)

Gerald F. Webers and Ellis L. Yochelson
A revision of Palaeacmaea (Upper Cambrian) (?Cnidaria)
Journal of Paleontology (July 1999) 73 (4): 598-607


Palaeacmaea typica, the type species of the genus, and P. irvingi, the only other Late Cambrian taxon considered congeneric are redescribed herein. Their morphology suggests that they are neither Monoplacophora, where they are currently assigned, nor are they Mollusca. Specimens of P. irvingi demonstrate considerable variation in shape, interpreted as distortion of a flexible integument, of essentially no thickness. A neotype is designated for P. irvingi; it is interpreted as a medusiform fossil, possibly a cnidarian. Only the holotype of P. typica is known, but it shows comparable features. The genus and the family Palaeacmaeide are placed in Phylum Incertae Sedis. Four Ordovician species previously assigned to palaeacmaea, show none of the characteristics noted, and they are tentatively reassigned to other genera.

ISSN: 0022-3360
EISSN: 1937-2337
Serial Title: Journal of Paleontology
Serial Volume: 73
Serial Issue: 4
Title: A revision of Palaeacmaea (Upper Cambrian) (?Cnidaria)
Affiliation: Macalester College, Geology Department, Saint Paul, MN, United States
Pages: 598-607
Published: 199907
Text Language: English
Publisher: Paleontological Society, Lawrence, KS, United States
References: 38
Accession Number: 1999-062830
Categories: Invertebrate paleontology
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus.
N40°30'00" - N45°00'00", W79°45'00" - W71°55'00"
N42°30'00" - N47°00'00", W92°49'60" - W86°45'00"
Secondary Affiliation: U. S. National Museum of Natural History, USA, United States
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute.
Update Code: 199921
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