Genus Synacanthotermes · 聚刺白蚁属

Morphology

The descriptions below are an adaptation of the original genus-level accounts; terms follow the meaning of the source, and the original is not transcribed verbatim.

Diagnostic characters

The alate is now known (the alate of trilobatus is the former angolensis, described by Weidner 1956). The antennae of both soldier and worker have 15 segments, segment 2 longer than segment 3; the soldier is eyeless, the frontal gland opening and frontal gland perhaps absent, the sides of the head parallel and flatly convex; the pronotum is small, less than half the head width, and weakly saddle-shaped. Holmgren recognised only one species (heterodon, Cameroon) and placed it among the fungus-growing termites.

Soldier

Head elongate, sides parallel, slightly narrowed anteriorly from the antennal sockets, flatly convex, eyeless. Cranial suture invisible; frontal gland opening and frontal gland perhaps absent. Frons flat, antennal carinae distinct. Clypeus short: the anterior margin of the base completely straight, bounded at the sides by the large mandibular basal segments; the apical piece fairly short and transparent. Labrum large and wide, narrowed at the base, with a trilobed transparent tip. Mandibles slightly geniculate near the middle, weakly curved, the apex fairly long; the left mandible with 3 teeth from the middle to the base, tooth 1 the largest, the base of the apex often with a slight notch; the right mandible with only one large step-like tooth at the base. Antennae of 15 segments, segment 2 longer than segment 3. Postmentum rectangular, elongate. Pronotum small, far narrower than the head, weakly saddle-shaped. Fore tibia with 3 apical spurs, the fore and mid tibiae with several shorter lateral spines in addition. Cerci relatively large and thick, styli degenerate.

Worker

In two forms. Head large, relatively flat, oval with parallel sides. Frontal gland opening very indistinct, cranial suture invisible. Clypeus slightly convex, the base shorter than half its width, posterior margin fairly strongly convex and anterior margin slightly concave, the apical piece fairly large and transparent, the mandibular basal segments fairly large. Labrum longer than wide, with a chitinous band. Left mandible with the Termes-type dentition, tooth 2 larger than tooth 1; right mandible with a degenerate tooth 2, tooth 3 larger than tooth 1, the inner margin as in Leucotermes. Antennae of 15 segments, segment 2 larger than segments 3 and 4. Pronotum saddle-shaped, both anterior and posterior margins concave, less than half the head width. Cerci relatively large and thick, styli present.

Sources: Holmgren, N. 1912. Termitenstudien 3. Systematik der Termiten. Die Familien Mastotermitidae, Protermitidae und Mesotermitidae. Kungliga Svenska Vetenskapsakademiens Handlingar 48(4): 1–166, Taf. 1–4., p. 21（archive.org 项 biostor-184513 页面图像） This text is an adaptation, not a verbatim transcription of the original.