Rhinarium: a nostril piece or portion of the nasus: q.v.: in Odonata, the lower portion of clypeus = ante-clypeus; q.v.
Rhipiptera: = Strepsiptera q.v.
Rhomboidal: having the form of a rhomb.
Rhombus: a quadrangular figure having its four sides equal and its opposite lines parallel, with two opposite angles acute and two obtuse.
Rhopalocera: that series of Lepidoptera in which the antenna are alike in both sexes and form a club at tip.
Rhodoptera: apterous insects with sucking mouth structures.
Rhophoteira: an ordinal term for the fleas (Clairville).
Rhynchophora: that section of Coleoptera, in which the head is produced into a snout, at the end of which the mouth structures are situated; gular sutures confluent: prosternal sutures wanting: the weevils.
Rhynchota: = Rhyngota: q.v.
Rhynchus: of Fabricius, = promuscis: q.v.