Adult male large, the length slightly varying; some specimens reach 1/8in.; expanse of wings, 1/4in.; length of antennæ, about 1/8in. Body red, with a shining, diamond-shaped, black patch on the dorsal surface of the thorax; legs and antennæ black. Wings dark-brown with (in some lights) a bluish tinge, marked with oblique, narrow, wavy stripes; main nervure red, branching once; there are also two longitudinal, whitish, narrow bands.[U] Antennæ very long and slender, with ten joints, which may easily be taken for nineteen, for, after the first which is short, round, and simple, all the other nine have two dilated portions with a constriction in the middle, and on each dilation is a ring of very long hairs, giving the antenna a feathery appearance.[V] Eyes very large and prominent, almost pedunculated, brown, divided into numerous semi-globular facets. Feet long and very hairy; coxæ short and thick, tibiæ long and slender, claw thin; upper digitules absent, lower pair only short bristles. Abdomen slender, segments somewhat distinct; on each segment some hairs; the last segment ends in two thick, conspicuous, cylindrical processes, which, in side view, are seen to incline upwards, and beneath them is the short, conical spike sheathing the penis. Penis red, longish, tubular, and thick, with many recurved short hairs, and at the end a ring of short spines. Each of the two processes on the last segment bears three or four long setæ, but there do not appear to be any of the long cottony appendages seen in the males of most Coccids.
[U] Signoret (Ann. de la Soc. Ent. de France, 1875), under the genus Monophlebus, speaks of "les plis hyalins" as existing also in the wings of the males of that genus.
[V] Misled by similar appearances, Burmeister and Westwood assign twenty-five joints to the male antenna of Leachia fuscipennis.
Habitat—On wattle, pine, orange, lemon, cypress, rose, gorse, grass, and, in fact, on almost every kind of native and introduced plants, Nelson, Hawke's Bay, Auckland. It will probably appear also elsewhere, but the climate of Canterbury and Otago may prove too cold in winter for it.
Allied to I. sacchari, Guérin, which damages sugar-canes in Mauritius; but differing in the formation of the ovisac, the presence of the marginal tufts and spinneret tubes in the female, and in other particulars. The male of I. sacchari has not been described. The male of I. Purchasi is probably quite distinct.
This species is supposed to have come originally from Australia. It has been very injurious to orange and lemon trees at the Cape of Good Hope and in California. In Auckland it has destroyed whole orchards of the same trees, and in Nelson and Hawke's Bay it is a dreadful pest on all kinds of plants.
Tree-growers should especially beware of this insect, and the best plan to adopt would be to burn at once any tree found infested with it.
N.Z. Trans., Vol. XII., 1889, p. 294.
Adult females with antennæ of eleven joints; segmented; naked, active; at gestation becoming stationary and enclosed in a thick mass of white cottony secretion. Anal tubercles absent or inconspicuous. Rostrum and mentum absent in the adult female.