Zarcosia ilonae n. sp.

(Figures 1; 3c; 4g; 5k; 6b)

Etymology. The species is named after my wife, Ilona Grunwald, to acknowledge her patience and support of my work with insects.

Type locality. Thailand: Surat Thani Province, Phanom District, Tham Wararam, 08°52’ N 98°39’ E .

Distribution. Thailand (Figure 1).

Description. (Figure 3c). Female unknown. Body length. ♂ holotype: 2.55 mm. Slender, orange-brown with darker head, covered with very short, pulverulent, white pubescence. Appendages pale.

Head. Moderately transverse, barely wider than pronotum. Palpi yellow, last article securiform. Finely and densely punctuated. Occiput lined with a fringe of dense and short white hairs posteriorly.

Antennae. 1.5 times longer than elytra, entirely yellowish, filiform with antenommeres 3–10 elongated.

Pronotum (Figure 6b). Convex, slightly longer than wide, sides regularly curved, wider, almost gibbose in its anterior third.

Elytra. Length: 1.80 mm. Punctation strong and dense, with larger points. Space between points slightly wider than the points themselves. Disc subconvex. Pubescence dense and short, comprised of very short hairs borne from the points and interspersed pulverulent hairs.

Legs. Particularly elongated. Foretibia weakly broadened in the middle of their inner side (Figure 5k).

Aedeagus (Figure 4g). Sturdy, lightly pigmented, sides divergent from base in dorsal view, then largely rounded near apex and ending in a broad stinger. Nearly flat in lateral view, with no kink. Lateral appendages thick and as long as the apical stinger.

Type material. Holotype (♂, MNHN). Thailand: Surat Thani Province, Phanom District, Tham Wararam, Cave, 08°52’ N 98°39’ E (250 m) (L. Deharveng and A. Bedos) 24.VII.1987.

Note. The extremely thin and elongated appendages of species likely represent adaptations to life in caves.