CONCHOSTRACAN CARAPACE RIBS

Strong radial ridges radiating from and across umbo of conchostracan carapace, with intervals of variable width between any pair and commonly nodose at intersections of growth lines; may be partial or embryonic in expression; synonyms include longitudal striae, carinae, radials, diagonal ridges, radial costae, and keels. (Characterize Leaiidae, never exceeding five in number on any given leaian valve; ribs also occur in Protomonocarina and Limnadiopsileaia.) [Moore and McCormick, 1969].

(ARTHROPODA: Crustacea)

Strong radial ridges with intervals of variable width radiating from and across the umbo, usually nodose at intersections of growth lines.