Aenictosymbia Maruyama, gen. n.

(Figs. 10–32)

Type species: Aenictosymbia cornuta Maruyama, sp. n.

Description. Body (Figs. 10–12) myrmecoid, slender, glossy.

Head (Figs. 10–13) almost spherical, with horn on anterior part of frons, gently narrowed posteriad, constricted at base to form “neck”; medial area of head slightly depressed; eyes moderate in size, prominent; antennae (Figs. 10–13) generalized, but segment I strongly thickened.

Mouthparts: Labrum (Fig. 14) generalized, rather irregularly with setae, without pseudopores; hypopharynx (Fig. 14) with mesal area bearing 3 campanifom sensillae, 3 setulae antero-medially, 4 setulae along lateral margin. Mandibles (Fig. 15) almost symmetric, but left mandible slightly thicker, with 2 patches of minute pseudopores around mesal area of dorsal disc, and 2 setae near base of outer margin. Mentum (Fig. 16) sub-trapezoidal, with 2–4 pseudopores, several setae around lateral margin. Labium (Fig. 17): apodeme with lateral lobe short, gently curved, rounded at apex, without medial projection; prementum with 2 real pores and 1 setal pore antero-laterally, strongly sclerotized along anterior margin to connect both bases of palpi; palpus with segment I long, more than 2 time as long as II, with patch of some minute setae near base (Fig. 17: arrow; probably sensillae); segment III narrow, elongate; maxilla (Fig. 18) generalized, no or few pseudopores overall; lacinia with 5 spines near apex, densely with pubescence; galea curved near apex.

Pronotum (Figs. 10–12, 19, 20) elongate, constricted around basal 1/3, shallowly sulcate at midline; prosternite (Fig. 20) subtriangular, elongate, convex at midline; triangular sclerite present (Fig. 20: arrow) from middle to near base of cavity.

Mesoventrite (Fig. 21) short, completely fused with metaventrite, weakly carinate between processes of both; metaventrite long, more than 2 times as long as mesoventrite; mesocoxal cavity slightly margined postero-laterally. Elytra (Fig. 22) rounded, well convex above; hind wings developed.

Legs (Figs. 23–25) long, slender; claws developed; fore leg (Fig. 23) with coxa projected at base; base of femur projected ventrad; tarsal segments subequal in length; mid leg (Fig. 24) with coxa small, slightly longer than trochanter; tarsal segments becoming smaller from base to apex; hind leg (Fig. 25) with coxa deeply notched at middle (Fig, 25: arrow); tarsal segments becoming smaller from base to apex.

Abdomen strongly constricted at base (segments II–VI); tergite II rather long, shallowly emarginate on anterior margin; tergite III elongate, dilated apicad; sternite III with posterior area strongly triangularly convex (Fig. 11: arrow; no distinct gland openings); tergites IV–VII short, transverse; stermites IV–VII large, strongly convex; tergite VIII with anterior margin rounded, without pseudopores or minute setae; sternite VIII with anterior margin slightly produced, rounded; tergite and sternite IX fused at base of tergite X of which anterior margin submembranous, truncate.

Male: median lobe of aedeagus (Figs. 29, 30) urceolate, strongly produced paramerally at base, with a pair of exposed sclerites of internal sac; paramere (Fig. 31) with basal part of paramerite short, narrow; velum extended near apex of apical lobe.

Female: spermatheca (Fig. 32) coiled at base, with apical part small.

Differential diagnosis. This genus is similar to Aenictophila Seevers, 1965, in general appearance, the states of meso- and metaventrites, and abdomen, but the convexity of the abdominal sternites is simpler in Aenictosymbia . In Aenictophila, the posterior areas of both sternites III and IV are strongly convex, and their surfaces have distinct gland opening patches, including trichome-like bundles of pubescence on sternite III.

Etymology. A combination of the host genus name Aenictus, and the Greek words syn (meaning "with", "together") and bios (meaning "life", "living"), meaning a symbiont of Aenictus ants. Gender feminine.

Distribution. Central Thailand.

Systematic notes. This genus apparently belongs to the Aenictophila generic group, which is composed of myrmecoid genera of Lomechusini, namely, Aenictophila, Mimaenictus Kistner & Jacobson, 1975, Procantonnetia Kistner & Jacobson, 1975, Weissflogia Kistner, 1997. These genera including Aenictosymbia share an exoskeletal modification of a gland on abdominal sternite III (III–V in some genera). This characteristic, including the presence of a gland on sternite III, is not observed in other Lomechusini genera and suggests monophyly of the generic group. Phylogenetics and a detailed morphological study are in progress by MM and his colleagues.