Sphenophyllum

noun

Sphe·​no·​phyl·​lum

ˌsfēnəˈfiləm

: a genus of Paleozoic fossil plants that are related to the club mosses and horsetails but are usually placed in the separate order Sphenophyllales, that have jointed stems, cuneate leaves in whorls of three or multiples of three, and terminal cones or sporophylls, and that occur from the Devonian to the Permian

Word History

Etymology

New Latin, from sphen- + -phyllum

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