Actinistia
plural noun
Ac·ti·nis·tia
\ˌak-tə-ˈni-stē-ə\
Definition of Actinistia
: an order (superorder Crossopterygii) of chiefly Mesozoic fishes including the family Coelacanthidae having the interspinous bones supporting each dorsal and anal fin fused into one piece — compare latimeria
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Origin and Etymology of actinistia
New Latin, from actin- + -istia (from Greek histion web, cloth, sail); akin to Greek histos mast, weaver's beam, web
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