Zygocycloides
Zygocycloides magnus
CMNH PT 620
Scale bar is 1 cm
Species
Zygocycloides blairi Smith and Wilson, 1995
Occurrence: Grant Lake
Reference: Smith and Wilson, 1995
Has tubercle-free cupules and strongly bifid crests on all marginal ossicles
Zygocycloides magnus (Miller & Dyer)
Occurrence: Fairmount, Bellevue, Corryville, Mount Auburn, Arnheim
Reference: Dalvé, 1948; Smith and Paul, 1982
Formerly known as Cyclocystoides magnus; Includes Cyclocystoides bellulus; Cyclocystoides minus (Miller & Dyer) is thought by Smith and Paul (1982) to be a juvenile, poorly weathered Z. magnus
Characterized by 20 marginal ossicles, with distinctive axe-head shape of the crest of the marginal plates
Zygocycloides marstoni (Salter)
Occurrence: Edenian
Reference: Smith and Paul, 1982
Characterized by 18–20 marginal ossicles, with marginal plates tending to be broader than long
