Tarditermes contracolor Emerson, 1960 反色慢白蚁

Morphology

The description below is paraphrased from the original or a later revision, by caste; the source is cited at the end.

Diagnostic characters

The alate has a very long apical tooth on the left mandible (index 2.91 according to Emerson and 3.17 according to Sands, the two accounts being inconsistent), marginal tooth 2 absent, and the molar plate without transverse ridges; the postclypeus is 2.1 times as wide as long, the fontanelle is a pale circular spot, the compound eyes project slightly from the sides of the head, and the pronotum is nearly semicircular. The soldier is monotypic: the nasus is long, thick and conical, reaching the large fontanelle at its apex, the mandibles lack a point, the anterior margin of the labrum is wavy, the head capsule is not constricted and in dorsal view is a rounded rectangle that is wider than long to the base of the nasus, and there are 13 antennal segments, setae occurring only at the apex of the nasus together with scattered minute hairs. In the worker the molar plate is weakly concave near the base and the anterior and posterior rounded ridges are more pronounced (index 3.23). Sands notes that its alate is larger than those of all closely related nasute genera except the Neotropical Angularitermes, the closest relative being Mimeutermes; the generic name derives from its extremely sluggish movement.

Alate

The head, postclypeus and pronotum are covered with fairly dense short hairs but not felted; a few setae occur on the margins of the head, postclypeus and pronotum. The wing membrane is densely covered with short hairs that are longer than those on the wings of most termites. Each abdominal tergite is densely covered with short hairs and bears a row of setae along its posterior margin, each about three times as long as the short hairs; the sternites are more densely haired, the hairs slightly longer than those of the tergites. The head is wide, with the sides nearly parallel near the compound eyes; the compound eyes are large and convex and lie about one seventh to one tenth of their diameter from the lower margin of the head; the ocelli are relatively large, smaller than the antennal sockets and slightly less than their own width from the compound eyes; the fontanelle is a small pale circular spot in the middle of the head; the postclypeus has a dark median line and is slightly more than twice as wide as long; there are 14–15 antennal segments. The apical teeth of the mandibles are very long and the cutting edge behind marginal tooth 1 is reduced; the left mandibular index is 2.91; the right mandible has no marginal tooth 2. The pronotum is large, slightly narrower than the head, with rounded lateral margins and a slightly concave posterior margin; the middle of the mesonotum has a rounded angle of about 130°; tibial spur formula 2:2:2. Measurements: head width 1.28–1.35 mm, compound eye diameter 0.41–0.42 mm, forewing 10.15–11.48 mm.

Soldier

The head and frontal projection bear minute hairs visible only in good light; there are no setae except near the apex of the frontal projection; the pronotum has a few short hairs and no setae. The head is relatively large and wide, and the conical frontal projection is thick at its base; the head capsule is not constricted. There are 13 antennal segments, the second and third about equal in length and the fourth slightly shorter than the third. The mandibles lack a point. The pronotum is relatively wide, its anterior margin without a notch or with only a very shallow one, and the anterior region is relatively large. Head length 2.41–2.65 mm, width 1.25–1.49 mm, hind tibia 1.12–1.19 mm.

Worker

The mandibles are as in the alate, except that the molar plate of the right mandible is weakly concave near the base and the anterior and posterior rounded ridges are more pronounced; the left mandibular index is 3.23.

This genus is monotypic, containing only this species; the following is the genus-level description based on the original literature; species-level measurements and intraspecific variation are given in the original.