Chasitermes Scheffrahn & Carrijo gen. nov.

Type-species.

Chasitermes pax Scheffrahn & Carrijo, sp. nov.

Diagnosis.

The combination of unsclerotized rectangular EVA cushions, a tubular extension of EVS, and a prominent spherical mesenteric tongue make C. pax unique among all Apicotermitinae genera.

Description.

Imago unknown. Worker. (Figs 1 - 4). Monomorphic. Head capsule and antennae light yellowish. Head covered with ca 50 longer (0.1 mm) setae and a few shorter ones (Fig. 1). In lateral view, dorsal surface of the head capsule slightly convex; postclypeus is moderately inflated. Antennae with 14 articles (formula 2>3≈4<5). Pronotum with about 20 long setae concentrated mainly at the borders and a few shorter ones. Mandibles with apical teeth very prominent; left mandible with M1 triangulate, shorter than apical; premolar process longer than M3 (Fig. 2A). Apical tooth of right mandible as long as that of left but narrower; M1 as long as M2. Fore tibia moderately inflated (Fig. 2C) with about a dozen thick posterior setae concentrated at the distal half; lateral and anterior surfaces with thinner long and shorter setae. Digestive tube (Fig. 3 with abbreviations) with voluminous crop; mesenteron forming half circle; mixed segment with prominent spherical mesenteric tongue. First proctodeal segment (P1) widens to maximum diameter before P2, enteric valve seating (EVS) slightly trilobed. Third proctodeal segment (P3) with long tubular extension of the EVS seating to main reservoir (Fig. 4C) then narrowing again toward P4 (Fig. 3D). Cuticle of EVA without sclerotization (Fig. 4A, B) forming six rectangular cushions with about 100 scales each (Fig. 4A). Scales proximal to P1 subrectangular, each with 5-10 creases; scales in distal one-third lacking creases, more scale-like with long fringes (Fig. 4B). Measurements are provided in Table 1.

Remarks.

The single most diagnostic character of the C. pax worker is the enteric valve armature which has unsclerotized rectangular cushions composed of creased or fringed scales. The tubular extension of the EVS in C. pax is closest to Patawatermes nigripunctatus (Emerson, 1925) but is much longer in the former and P. nigripunctatus lacks a trilobed enteric valve seating. The left mandible of C. pax has prominent premolar process closest to Patawatermes turricola (Silvestri, 1901) but it is narrower and longer in the former.

Etymology.

Named in honor of the collector, James A. Chase.