Echinotermes Castro & Scheffrahn

Castro, Daniel, Scheffrahn, Rudolf H. & Carrijo, Tiago F., 2018, Echinotermesbiriba, a new genus and species of soldierless termite from the Colombian and Peruvian Amazon (Termitidae, Apicotermitinae), ZooKeys 748, pp. 21-30 : 23-24

Echinotermes Castro & Scheffrahn gen. n.

Type-species.

Echinotermes biriba sp. n.

Imago. Unknown.

Description of worker.

(Fig. 1). Monomorphic. Head capsule and antennae a light yellowish colour; pronotum pale yellow; legs hyaline. Head covered with approx. 30 longer setae (0.1 mm) and approx. 100 shorter setae (≤ 0.05 mm) (Fig. 1A). In lateral view, dorsal surface of the head capsule slightly convex; postclypeus is moderately inflated. Antennae with 14 articles. Pronotum with four or five long setae and numerous short hairs. Mandibles with apical teeth more prominent than first marginal teeth; left mandible with M1+2 equilateral, M3 forming right angle, molar prominence projecting in line with apical tooth; right mandible with concave margin between M1 and M2 (Fig. 1B).

Fore-tibia moderately inflated (Fig. 1C) and covered with approx. 60 longer setae and approx. 40 shorter setae; pilosity denser apically. Third (external) spur very small. Femur with approx. 20 sparse large setae. Tibial spurs 2:2:2.

Digestive tube (Fig. 1D) with very large crop, more voluminous than paunch (P3). Mesenteron forming complete 360° loop. Mesenteric tongue short, truncate. First proctodeal segment tubular, equal diameter throughout and visible its entire length in ventral view. Enteric valve seating trilobed, with smaller lobe not visible in intact gut. Enteric valve with six cushions, terminating at the opening to the P3 as spiny spheroids (Fig. 2).

Diagnosis.

The crop of E. biriba is unusually large and the enteric valve armature, consisting of six spherical pectinate pads, is unique among all apicotermitine genera.

Remarks.

Mandibles of Rubeotermes jheringi and Humutermes krishnai are very similar to E. biriba , but the first marginal teeth of E. biriba are less prominent that those two genera. The diagnostic character of E. biriba is the enteric valve armature which is also spiked in the Humutermes enteric valve (EV) but in E. biriba the EV armature is spherical while in Humutermes it is rather flat. Humutermes species are smaller than Echinotermes . The enteric valve of Grigiotermes is composed of six uniform pectinate plates, while in Patawatermes the uniform plates are hemispherical.

Etymology.

From the Latin Echino, meaning spiny, describing the EV armature.