''Helcionopsis'' is an extinct genus of paleozoic
monoplacophora
Shell of Monoplacophora
Monoplacophora , meaning "bearing one plate", is a polyphyletic class of molluscs with a cap-like shell, inhabiting deep sea environments. Extant representatives were not recognized as such until 1952; previously they wer ...
n in the family
Tryblidiidae.
The
generic name is from the external resemblance which the genus bear to the recent species of the genus ''
Helcion
''Helcion'' is a genus of sea snails, true limpets, marine gastropod mollusks in the family (biology), family Patellidae.
Species
Species within the genus ''Helcion'' include:
Subgenus ''Ansates'' : accepted as ''Ansates'' G.B. Sowerby II x ...
'' in family Patellidae.
Species
Species in the genus ''Helcionopsis'' include:
* ''Helcionopsis radiatum">Patellidae">x ...
'' in family Patellidae.
Species in the genus ''Helcionopsis'' include:
* ''Helcionopsis radiatum'' (Lindström, 1884)
* ''Helcionopsis reticulatus'' Easton, 1943
* ''Helcionopsis striata'' Ulrich, 1897
* ''Helcionopsis subcarinata'' Ulrich & Scofield, 1897
'', from which ''Helcionopsis'' differ in having the surface marked by fine radiating striae.
Muscular scars of this genus ''Helcionopsis'' unknown in 1897, when the genus was described.
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