Anal loop: Odonata; the loop formed by the angulations of 1st anal vein.
Analogous: similar in function; but differing in origin and structure: e.g. the wings of birds and insects: see homologous.
Anal operculum: the dorsal arch of the 10th abdominal segment; in caterpillars = supra-anal plate, q.v.
Anal organs: Collembola; the two modified hairs arising from a tubercle ventro-cephalad of the anus and usually curving caudo-dorsad.
Anal orifice: see anus.
Anal papilla: Collembola; see anal tubercle.
Anal plate: in caterpillars, the shield-like covering of the dorsum of the last segment: in the embryonic larva the 11th tergite.
Anal ring: a chitinous ring encircling the anus in many Coccidae.
Anal scale: one of the lateral processes of the ovipositor in Cynipidae, lying outside and below the lateral scale.
Anal siphon: the anal breathing tube of Culicid larvae.