18, 21 b); the body shortened, with the abdomen swollen, but protected with tubercles and spines, and with longish legs adapted for an active life, as in the predaceous larvae of ladybirds; the body soft-skinned, swollen and caterpillar-like, with legs well developed, but leading a sluggish underground life, as in the grub of a chafer; the body soft-skinned and whitish, and the legs greatly reduced in size, as in the wood-feeding grub of a longhorn beetle.
Kolbe (1901), who recognizes three sub-orders: (i.) the Adephaga; (ii.) the Heterophaga, including the Staphylinoidea, the Actinorhabda (Lamellicornia), the Heterorhabda (most of Sharp's Polymorpha), and the Anchistopoda (the Phytophaga, with the ladybirds and some allied families which Sharp places among the Polymorpha); (iii.) the Rhynchophora.
Now, Coccinellidae (ladybirds) are known to be highly distasteful to most insectivorous mammals and birds, and snails would be quite unfit food for the Pompilid or Ichneumonid larvae, so that the reason for the mimicry in these cases is also perfectly clear.
In the Philippines, a cricket (Scepastus pachyrhynchoides), has taken on the shape and coloration of a species of Apocyrtus, a hard and inedible weevil (Curculionidae); and Phoraspis, a kind of grasshopper similarly resembles ladybirds (Coccinellidae).