Genus Tiunatermes · 暗鼻白蚁属

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 soldier shares with Anhangatermes and Cyranotermes 13-segmented antennae, a head length including the nasus greater than 1.90 mm, a relatively long nasus and sparse setae on the head capsule; with Anhangatermes it further shares a broad head that is wider than long, mandibles with a distinct outer margin, and numerous short hairs at the tip of the nasus. It differs from Anhangatermes in: the nasus conical (cylindrical in the latter); the anterior surface of the fore coxa without a projection (with one in the latter); the abdominal sclerites strongly sclerotised and the tergites imbricate (sclerites unsclerotised in the latter, the gut coiling visible through them, tergites not imbricate). The generic key (supplemented by Constantino 2002) leads to this genus by 'nasus conical; fore coxa without a projection; abdominal sclerites sclerotised; tergites imbricate'.

Soldier

Monotypic; head capsule broad in dorsal view, without a constriction; nasus conical, broad at the base; mandibles with a distinct outer margin, not forming a clear 'point'; antennae 13-segmented; postclypeus slightly convex in lateral view; labrum wider than long, anterior margin rounded, lateral margins parallel, anterior corners rounded; anterior and posterior lobes of the pronotum equally developed, enclosing a 90° angle; fore coxa conical, without a ridge, its anterior surface without a projection; tibial spur formula 2:2:2; abdominal sclerites strongly sclerotised, tergites imbricate, intersegmental membranes not visible.

Worker

Head capsule nearly trapezoidal in dorsal view, posterior margin rounded; fontanelle oval, situated in the posterior 1/3 of the head capsule; the surface of the head capsule not depressed at the fontanelle (in the same plane in lateral view); postclypeus distinctly curved in lateral view; antennae 14-segmented; anterior lobe of the pronotum more developed than the posterior lobe, its anterior margin rounded, not concave; tibial spur formula 2:2:2. Apical tooth of the mandibles sharp and more prominent than the first marginal tooth, the posterior margin of the apical tooth slightly concave and forming an acute angle with the anterior margin of the first marginal tooth; in the left mandible M1+2 distinct, its posterior margin straight or slightly undulating, M3 greatly reduced, the tip of the molar tooth visible or faintly visible beneath the molar region swelling, the molar region swelling concave and without definite ridges; in the right mandible the first marginal tooth distinct, the second marginal tooth absent, the molar plate concave and without definite ridges, the basal notch distinct. Gut: crop more developed than the gizzard, the cuticle of the crop with pectinate scales; gizzard with a fully sclerotised hexaradiate armature, the pulvillar belt more developed than the columnar belt, pulvillus I well developed with long needle-like spines on its surface, pulvillus II reduced and smooth; mixed segment short, the midgut tongue outside the midgut arc and not constricted proximally; enteric valve (P2) lying beneath P1 and coaxial with P3, its armature an asymmetrical ring of alternating long and short pads, the surface of the long pads sparsely set with small, nearly triangular spines (larger on the posterior margin), that of the short pads with small spines, larger on the median and terminal surfaces, all spines curved in the direction of the food stream; enteric valve seating monolobed or trilobed.

Sources: Carrijo T.F., Cuezzo C. & Santos R.G. 2015. Tiunatermes mariuzani gen. nov. et sp. nov., a new nasute termite from the Brazilian savannah (Isoptera: Termitidae). Austral Entomology 54: 358–365. https://doi.org/10.1111/aen.12137, pp. 359–360（Genus Tiunatermes gen. nov.: Description / Comparisons） This text is an adaptation, not a verbatim transcription of the original.