Frontal: referring to the front of head or anterior aspect of any part.
Frontal costa: Orthoptera, a prominent vertical ridge of bead which may be median or lateral: see median carina and lateral carina.
Frontal fastigium: in Orthoptera, that process of the face extending dorsad between the antennae and meeting or nearly meeting the fastigium of the vertex in Tettigidae.
Frontal fissure: Diptera; the impressed line extending from the frontal lunule to the border of the mouth.
Frontal lobes: in Psyllidae, two lobes or swellings more or less completely divided by a suture in which an ocellus is situated.
Frontal lunule: Diptera; an oval or crescentic space above the base of antennae in Cyclorrhapha, bounded by the frontal suture.
Frontal processes: Diptera; = antennal process, q.v.
Frontal ridge: in Coleopteran; a sharp ridge on the dorsal margin of the eye, extending forward.
Frontal stripe: Diptera; the middle of the front when membranous or discolored: = vitta frontalis.
Frontal suture: Diptera; separates the frontal lunule from that part of the head above it: in Coleopteran; = clypeal suture.