Andixius nupta Emeljanov & Hayashi, 2007, original designation.

The distinctive characters proposed by Emeljanov and Hayashi (2007) are modified as follows: head including eyes distinctly narrower than pronotum. Apical transverse carina of vertex weak and low, meeting the main part of frons at slightly obtuse angle or arc. Subapical carina of vertex as strong as conjunct lateral carinae. A small almost quadrangular fossette between vertex and frons. Vertex narrowest at apex, widened to base, disc arcuately and deeply excavated, lateral carinae strongly elevated. Lateral carinae of frons and postclypeus foliate, directed forward; carinae of posclypeus slightly lower than those of frons. Lower part of frons with convex disc separated from lateral carinae; its upper part deeply trough-like. Frontoclypeal suture slightly arched dorsally at middle. Middle ocellus apart from postclypeus. Middle carina of frons only in lower part or absent. Clypeus with distinct median carina. Frontoclypeus compressed, without lateral carinae. Rostrum long, extended considerably beyond hind coxae. Antennae medium-sized; pedicellum rounded conical and isodiametric. Pronotum short, with anterior margin straight and posterior margin deeply emarginated in an angle; intermediate carinae of pronotum encircling eyes from behind and below. Lateral carinae of pronotum between eye and tegula, separating paranotal lobes of pronotum from upper part behind postocular carinae. Tegmina long, tectiform, gradually but distinctly expanded towards end, rounded at apex, ScR (ScRA and RP) forming a short common stalk. Legs simple, fore coxae without angular apical lobe, hind tibia with six apical spines.

This genus can be easily distinguished from other genera of Andini by the following characters: forewings without trifid branching of ScRA, RP and M near basal cell, ScR (ScRA and RP) forming a short common stalk. Legs simple, fore coxae without angular apical lobe.

China, Japan.

Checklist and distributions of species of Andixius Emeljanov & Hayashi

A. longispinus Zhi & Chen, sp. n., China (Yunnan).

A. nupta Emeljanov & Hayashi, 2007, Japan (Ryukyu).

A. trifurcus Zhi & Chen, sp. n., China (Yunnan).

A. venustus (Tsaur & Hsu, 1991), China (Taiwan).

Holotype: ♂, China: Yunnan, Lushui County, Pianma Town (26°N, 98°36'E), 16 August 2000, Xiang-Sheng Chen; paratypes: 1♂1♀, same data as holotype.

Body length: male 6.2–6.5mm (N = 2), female 7.2 mm (N = 1); forewing length: male 5.4–5.5 mm (N = 2), female 6.3 mm (N = 1).

Coloration. General color yellowish brown (Figs 1–2). Eyes brown, ocelli faint yellow, semi-translucent. Antenna, vertex, face and rostrum generally yellowish brown. Pronotum with discal area yellowish brown and lateral areas dark yellowish brown. Mesonotum with areas between lateral carinae yellowish brown, lateral areas brown. Forewing semi-translucent, costal vein with 3 small spaced dark brown spots; slightly behind stigma, near claval fork and behind clavus with an irregular tan spot respectively, basal and middle part of forewings with two inner oblique brown stripes; apical half of wing with brown patches. Hind tibiae and ventral abdomen yellowish brown.

Figures 1–4. 

1–2. Andixius longispinus sp. n., male. 1 Dorsal view 2 Lateral view 3–4. Andixius trifurcus sp. n., male 3 Dorsal view 4 Lateral view. Scale bars: 1.0 mm.

Head and thorax. Vertex (Figs 1, 5) 0.8 times longer than wide; anterior margin nearly straightly, posterior margin V-shaped recessed, median carina absent. Frons (Fig. 6) 2.6 times as long as wide. Pronotum (Figs 1, 5) 1.8 times longer than vertex; posterior margin obtuse-angled. Mesonotum 1.4 times longer than pronotum and vertex combined. Forewing (Figs 2, 7) 2.2 times longer than wide, with twelve apical cells and six subapical cells. Hind tibia with six lateral spines, usually small; chaetotaxy of hind tarsi: 7/6–7, 2^nd hind tarsus with 0–3 platellae.

Figures 5–16. 

Andixius longispinus sp. n., male 5 Head and thorax, dorsal view 6 Face, ventral view 7 Forewing 8 Hindwing 9 Genitalia, lateral view 10 Pygofer and genital styles, ventral view 11 Anal segment, dorsal view 12 Genital styles, lateral view 13 Aedeagus, right side 14 Aedeagus, left side 15 Aedeagus, dorsal view 16 Aedeagus, ventral view. Scale bars: 0.5 mm (5–6, 9–16); 1.0 mm (7–8).

Male genitalia. Pygofer (Figs 9–10) symmetrical, dorsal margin shallowly concave and U-shaped ventrally, widened towards apex, slightly concaved medially; in lateral view, lateral lobes trapezoidal and extended caudally. Medioventral process triangular in ventral view, apical margin rounded. Anal segment (Figs 9, 11) tubular, dorsal margin almost straight, ventral margin waved in lateral view; 2.6 times longer than wide in dorsal view; anal style strap-shaped, not beyond anal segment. Genital styles (Figs 10, 12) symmetrical ventrally, inner margin with a small curved process near base; in lateral view, dorsal margin bending inwards medially, apical margin pediform. Aedeagus (Figs 13–16) with six processes. Right side of periandrium with a slender process, curved downwards basally and paralleled with periandrium distally; another short reversed spinose process directed dorsocaudally arising from basal 1/3 of right side of periandrium. Ventral margin with a large projection near apex, of which basal 1/3 longitudinally and distal 2/3 horizontally extended, directed ventrocephalically. Left side of periandrium with a very short spinose process, directed ventrocaudally. Flagellum with two processes, semi-sclerotized, generally curved in left side; apex with a very fine process, curved dorsocephalically; a process arising from base of flagellum, along the dorsal edge of the flagellum, directed ventrocephalically.

China (Yunnan) (Fig. 29).

The specific name is derived from the Latin adjective long- and spinus, referring to the one long process arising from the base of the flagellum, along the dorsal edge of the flagellum.

This species is similar to Andixius nupta Emeljanov & Hayashi, 2007 in appearance, but differs in: (1) right side of periandrium with a short reversed spinose process at apical 1/3 (A. nupta without process in the same position); (2) left side of periandrium with a small process, not furcate (left side of periandrium with a large bifurcate process in A. nupta); (3) flagellum with two processes (without process in A. nupta).

Japan (Ryukyu) (Fig. 29).

Based on the description and the figures by Emeljanov and Hayashi (2007), this species can be distinguished from the other species of the genus by the following characters: left side of periandrium with a bifurcate process medially; left-ventral margin with a reversed process and right-ventral margin with a long process apically.

Holotype: ♂, China: Yunnan, Lushui County, Pianma Town (26°N, 98°36'E), 17–19 June 2011, Jian-Kun Long; paratypes: 4♂♂5♀♀, same data as holotype, Jian-Kun Long, Yu-Jian Li; same collecting site as holotype, 14 August 2006, Pei Zhang.

Body length: male 6.4–6.8mm (N = 5), female 7.9–8.2mm (N = 5); forewing length: male 5.4–5.9 mm (N = 5), female 7.1–7.3 mm (N = 5).

Coloration. General color yellowish brown (Figs 3–4). Eyes brown, ocelli faint yellow, semi-translucent. Antenna blackish brown. Vertex generally blackish brown with two short longitudinally yellow strips. Face generally brown. Postclypeus yellowish brown, rostrum yellowish brown except for apex dark brown. Pronotum with discal area light yellowish brown and lateral areas yellowish brown. Mesonotum brown. Forewing similar to Andixius longispinus sp. n., but without a tan spot near claval fork and distal half of forewing with larger brown patches. Hind tibiae and ventral abdomen yellowish brown.

Head and thorax. Vertex (Figs 3, 17) almost equal to width; anterior and posterior margin recessed in acute angle, median carina absent. Frons (Fig. 18), 2.6 times as long as wide. Pronotum (Figs 3, 17) 1.5 times longer than vertex; posterior margin recessed in a right angle. Mesonotum 1.4 times longer than pronotum and vertex combined. Forewing (Figs 4, 19) 2.3 times longer than wide, with twelve apical cells and seven subapical cells. Hind tibia with six lateral spines, chaetotaxy of hind tarsi: 6/6, 2^nd hind tarsus with two platellae.

Figures 17–28. 

Andixius trifurcus sp. n., male 17 Head and thorax, dorsal view 18 Face, ventral view 19 Forewing 20 Hindwing 21 Genitalia, lateral view 22 Pygofer and genital styles, ventral view 23 Anal segment, dorsal view 24 Genital styles, lateral view 25 Aedeagus, right side 26 Aedeagus, left side 27 Aedeagus, dorsal view 28 Aedeagus, ventral view. Scale bars: 0.5 mm (17–18, 21–28); 1.0 mm (19–20).

Male genitalia. Pygofer (Figs 21–22) symmetrical, dorsal margin shallowly concave and U-shaped ventrally, widened towards apex; in lateral view, lateral lobes trapezoidal and extended caudally. Medioventral process round in ventral view. Anal segment (Figs 21, 23) with dorsal margin nearly straight, ventral margin with an antler-like process extending to apex ventrally in lateral view; 1.6 times longer than wide in dorsal view; anal style strap-shaped, slightly beyond anal segment. Genital styles (Figs 21, 24) symmetrical ventrally, inner margin with a small odontoid process medially and an obtuse process near apex, gradually widened towards apex; dorsal and ventral margins subparallel, apical part strongly bent upward and apical margin truncated in lateral view. Aedeagus (Figs 25–28) with five large processes. Dorsal margin of aedeagus near apex with a long process, slightly directed ventrocephalically. Periandrium with an expanded semi-enclosed structure around the left side and ventral margin of periandrium, ventral margin of the expanded structure with three long processes: apical one wide, slightly curved and directed cephalically; middle one longest, narrowed from base to end, curved upwards and directed dorsocephalically; basal one wide, slightly curved and directed ventrocephalically. A slender process arising from apical 1/3 of left side of periandrium, directed ventrocephalically. Flagellum short and small, slightly sclerotized, without process.

China (Yunnan) (Fig. 29).

Figure 29. 

Geographic distributions of Andixius species: A. longispinus sp. n. (▲); A. nupta (▲); A. trifurcus sp. n. (●); A. venustus (■).

The specific name is derived from the Latin prefix tri- plus the Latin word furcus, referring to the trifurcated ventral margin of the periandrium.

This species is similar to Andixius longispinus sp. n. in appearance, but differs in: (1) dorsal margin of aedeagus with a long process near apex (A. longispinus without process in the same position); (2) periandrium with an expanded semi-enclosed structure around left side and ventral margin of periandrium (not as above in A. longispinus); (3) flagellum without process (two processes in A. longispinus).

China (Taiwan) (Fig. 29).

Based on the description and the figures by Tsaur & Hsu, 1991, Andixius venustus closely resembles A. nupta Emeljanov & Hayashi, 2007, but can be distinguished from the latter by the following characters: (1) right side of flagellum with a large bifurcate process basally (flagellum without process in A. nupta); (2) left side of periandrium with a medium process apically and without process medially (A. nupta without process apically and with a bifurcate process medially).