Aenictobia siamensis Maruyama, sp. n.

(Figs. 1 – 9)

Type series. Holotype, ♂, " THAI: Nakhon Ratchasima, / Khao Yai National Park, / Heaw Suwat (750 m), / 30 IX 2007, Maruyama M., / Komatsu T. & Katayama Y. / MM-AE029 // HOLOTYPE / Aenictoxenides / mirabilis / det. Maruyama, 2014" (male 8th abdominal segment and aedeagus dissected and mounted in Euparal) (KUM) . Paratypes, 1♀, 7 sex?, same data as holotype (KUM, DNP); 8 sex?, " THAI: Nakhon Ratchasima, / Khao Yai National Park, / Kong Kaew (700 m), / 1 X 2007, Maruyama M. / MM-AE032" (KUM, DNP) ; 2♂, 2♀, 25 sex?, " THAI: Nakhon Nayok, / Khao Yai National Park, / near Cafeteria (700 m), / 3 X 2007, Maruyama M., / Komatsu T. & Katayama Y. / MM-AE036" (KUM) .

Description. Body (Figs. 1–3) small. Light reddish brown, but head, elytra and posterior part of abdomen darker; sometimes elytra dark brown.

Head (Figs. 1–3) with process between antennal cavities strongly projected; eyes large, more prominent than temples. Antennae (Figs. 1–3) slender, with all segments longer than wide; segment I as long as II and III combined; segment IV–X gradually becoming longer and wider toward apex; segment XI slightly longer than X.

Pronotum (Figs. 1–3) almost circular, narrower than elytra, with postero-lateral corners indistinct, slightly depressed behind anterior margin. Elytra (Figs. 1–3) longer than pronotum,

Abdomen with tergite VIII (Fig. 4) shallowly emarginate at apex, with 4 short macrosetae; sternite VIII (Fig. 5) with 5 macrosetae.

Male: Median lobe of aedeagus (Figs. 6, 7) crista apicalis acutely prominent; apical lobe of paramere (Fig. 8) oblong oval, with 2 large setae near base.

Female: Spermatheca (Fig. 9) with apical part strongly swollen.

Measurements. BL, ca. 2.0 – 2.3; FBL, ca. 1.0 – 1.2; HW, 0.33 – 0.37; AL, 1.42 – 1.55; PL, 0.38 – 0.43; PW, 0.44 – 0.54; HTL, 0.36 – 0.41 (N=5).

Differential diagnosis. This species is similar to A. longicornis and A. thoi in the slender antennae but distinguished from them by the body being clearly bicolored, the smaller body length, the more circular pronotum, and the eyes being more prominent.

Etymology. Named after Siam, an old exonym of Thailand.

Symbiotic host. Aenictus hodgsoni .

Distribution. Central Thailand.