Males with prominent, facetted eyes; ocelli absent. Abdomen without tassels.
In one New Zealand species the female in the second stage is stationary, enclosed in a thick, hard mass of waxy secretion, of which some account is given in Chap. III. The other species included in this work inhabits a remote and scarcely visited district, and the female has not hitherto been found; it is not possible therefore to include the excretion of wax and the stationary position amongst the generic characters at present.
This genus is allied to Porphyrophora, Brandt, and to Monophlebus, Leach; differing from the former by the presence of an œsophagal orifice, and from the latter by the absence of tassels on the abdomen of the male. In the genus Ortonia, Signoret, the female possesses a rostrum and mentum.
66. Cœlostoma zealandicum, Maskell.
N.Z. Trans., Vol. XII., 1879, p. 294; Vol. XIV., 1881, p. 226; Vol. XVI., 1883, p. 141.
([Plate XX.]; [Plate XXI.], Fig. 1.)
Adult female brick-red, elongated, distinctly segmented, convex; length about 1/2in.; before gestation active, naked or covered with thin meal; during gestation stationary, enclosed in a thick mass of white cotton. Antennæ of eleven joints, tapering to the tip; the joints all nearly equal, and bearing several hairs. Feet black, short, strong; all the pairs placed somewhat forward; digitules absent, a short seta at the base of the claw; on the inner edge of the tibia and tarsus a fringe of strong hairs; on the trochanter a long hair. Rostrum and mentum absent; mouth represented by a minute orifice between the second pair of feet. Eyes very minute, tubercular, projecting, placed behind the antennæ. Anal tubercles absent; anogenital opening small, elliptical, simple, hairless. Body flattish beneath, more convex above; segments distinct, generally smooth, sometimes bearing hard projecting callosities. Skin covered with minute hairs interspersed with circular spinnerets.
Female of second stage deep-red in colour, nearly globular, very indistinctly segmented; stationary, enclosed in a thick, hard solid test of yellow wax; tests attaining sometimes the size of a large pea; enclosed insect averaging 1/5in. in length. Insect filling the test; skin smooth, very thin; general appearance like a hard, round, smooth ball. Anal tubercles absent; anogenital ring small, simple, hairless: from this ring springs often a tuft of short white cotton, and a long white cottony seta protruding through an orifice in the test. Rostrum and mentum present, very small; mentum triarticulate, with a few hairs at the tip. Antennæ very short, of eight joints, conical, tapering to the tip, hairy. Feet atrophied, bloated-looking, apparently only consisting of a very short femur, tibia, and tarsus; digitules two, very small. Skin covered with a great number of circular spinnerets of two sizes, the larger ones simple, the smaller multilocular. Tracheæ very large; spiracular orifices containing brown tubes with beaded extremities on the inner end. Anal extremity dark-brown, the anal ring in the centre; spinnerets here very numerous, converging towards the anus. Insect in this stage emitting a strong, persistent, and fetid odour.
Young larva brick-red, elongated, active, naked; length, about 1/24in. Antennæ of six joints, hairy; last joint the largest, clavate. Eyes and feet as in adult, but there is no fringe on the tibia and tarsus. Rostrum and mentum large, conspicuous. Skin covered with circular spinnerets and minute hairs; the spinnerets are most numerous on the abdomen. Anogenital ring apparently folded. At the extremity of the abdomen two long hairs springing from quadrate tubercular bases which represent the anal tubercles.
Adult male red or purplish in colour, wings bluish-purple with red nervures; length, about 1/5in.; width across expanded wings, about 1/2in. Eyes large, prominent, facetted. Antennæ of ten joints, each joint bearing many hairs. Feet long, slender, with somewhat large trochanter; on the tibia and tarsus a fringe of hairs as in the female. Upper digitules two long fine hairs; lower digitules absent. The nervure of the wings branches twice at least. Haltere large, inflated, sac-like; bearing four curling setæ. Abdomen distinctly segmented, each segment bearing many fine short hairs and several small circular marks. Abdominal spike short, broad, bivalvular; penis protruding as a long soft white tube covered with minute recurved hairs.