The plural form referring to lateral portions or winglike structures on the ventral side of an insect's elytra (wing covers).
From Greek 'epi' (upon) + 'pleura' (side or rib), anatomical term for structures along the sides of insect thorax.
Beetles have specialized epipleura that tuck their delicate hindwings safely underneath their hardened elytra, a design engineers study for protective folding mechanisms.
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