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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Merriam-Webster unabridged
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Time Traveler for Actinistia
The first known use of Actinistia was in 1871
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