label: wing vein
label_lc: wing vein
description: "Wing veins are epidermal sclerotizations above hemolymph lacunae that run between the dorsal and the ventral wing surfaces and carry trachea and nerves. The two-dimensional pattern of wing veins is the result of the cuticular differentiation of stripes of epidermal cells on the wing blade, which can be contrasted with the two-dimensional pattern of sensory organs derived from discrete cells."