Key to males of Parachorius

Parachorius species are reliably identified only using males. A separate key to the identifiable females is provided in the next section. The species are illustrated in Figs. 6–24 and their distribution maps are given in Figs. 25–27.

1 Clypeus with two teeth, outer margin of each tooth not notched basally (Fig. 4F–G).................................2

- Clypeus with two teeth, outer margin of each tooth distinctly or slightly notched basally (Fig. 4D–E)..................10

2 Clypeus with two distinctly produced teeth (Fig. 4G).........................................................3

- Clypeus with two less produced teeth (Fig. 4F ............................................................... 5

3 Body black; parameres widely rounded; head triangularly shaped (Fig. 21); size 6.5–6.8 mm; southern China........................................................................................ P. schuelkei Tarasov new species

- Body reddish brown, rarely dark brown; parameres either claw shaped or apically acute but not widely rounded; head more rounded and not as distinctly triangular as in P. schuelkei ......................................................4

4 Protibia with first tooth somewhat modified in male—slightly thickened and spatulate; parameres notched basally and claw shaped in lateral view (Fig. 14); length 6.7 mm; known only from the holotype; Java ........ P. javanus (Boucomont, 1914)

- Protibia first tooth not modified in males; parameres medially narrowed (in lateral view), apically acute (Fig. 20); length 6–7 mm; Java ............................................................. P. pseudojavanus Tarasov new species

5 Metatibia strongly curved and notched medially (Figs. 16C, 17D); frontal angles of pronotum from moderately to distinctly sharp (Figs. 16B, 17C, E–F).............................................................................6

- Metatibia slightly sinuate (Fig. 24E); frontal angles of pronotum rounded (Fig. 24G)................................7

6 Middle part of metafemur dilated posteriorly and produced as a large, rounded angle; pronotum distinctly angulate laterally with frontal angles moderately sharp (Fig. 17); length 7.8–8.0 mm; southern Laos...... P. newthayerae Tarasov new species

- Metafemoral posterior margin simple, metafemur not dilated; pronotum presumably (as none of the specimens were studied) not angulate laterally with frontal angles distinctly sharp (Fig. 16); length 6.5–6.8 mm; central Thailand.......................................................................... P. maruyamai Masumoto, Ochi, & Sakchoowong, 2012

7 Elytra covered with dense contiguous and rugose punctures (Fig. 10F); pronotum almost as long as elytra; wings reduced (Fig. 10); 6–7 mm; northeastern India....................................................... P. globosus Arrow, 1931

- Elytra covered with sparse (not contiguous) punctures (Fig. 24F); pronotum notably shorter than elytra; wings normally developed............................................................................................... 8

8 Metafemoral posterior margin with two distinct denticles, apical denticle is produced and spur-like; metatibial inner margin excavated apically; metafemoral posterior margin not serrate; parameres of aedeagus simple, apex slightly rounded, triangularly shaped (Fig. 24); length 6.5–9.0 mm; eastern India, Myanmar, Thailand, Laos ............. P. thomsoni Harold, 1873

- Metafemoral posterior margin without pair of distinct denticles, simple or dilated, either serrate or not; metatibial inner margin not excavated apically; parameres of aedeagus simple, apex widely rounded and inferiorly angulate....................9

9 Metafemoral posterior margin serrate (sometimes slightly) and varies from simple, not modified, to dilated; metatibial inner margin produced in small angle apically (Fig. 9); length 6.5–9.0 mm; southern China, Myanmar, Indochina.............................................................................. P. fungorum Kryzhanovsky & Medvedev, 1966

- Metafemoral posterior margin simple, not serrate, not dilated; metatibial inner margin straight, not produced apically (Fig. 12); size 6.0 mm; northern India........................................................... P. hookeri Arrow, 1931

10 Outer margin of each clypeal tooth slightly notched basally (Fig. 4E)............................................ 11

- Outer margin of each clypeal tooth distinctly notched basally (Fig. 4D)......................................... 12

11 Inner margin of metatibia denticulate with relatively small teeth; protibia with apical tooth wide, nearly merging with second tooth; parameres elongate and rounded apically; length 5–6 mm (Fig. 11); Taiwan............. P. gotoi (Masumoto, 1986)

- Inner margin of metatibia denticulate with large teeth (sometimes denticulation obliterated); protibia with apical and second teeth distinctly separated from each other; parameres bear membranous lobes and bent upward apically; length 8.2–10.6 mm (Fig. 22); northern Laos................................................. P. semsanganus Tarasov & Keith, 2011

12 Parameres asymmetrical; humeral area of elytron usually with yellow spot, sometimes yellow spot absent and elytra uniformly colored (Fig. 6); length 4.5–4.7 mm; India.................................... P. asymmetricus Tarasov new species

- Parameres symmetrical; humeral area of elytron with or without yellow spot.....................................13

13 Parameres with horn-like upper lobes dorsally (Fig. 5M–O)...................................................14

- Parameres normal, without horn-like upper lobes (Fig. 5G–H).................................................16

14 Humeral area of elytron usually (but not always) with yellow spot; inner margin of metatibia not denticulate; metafemoral posterior margin usually greatly dilated apically, less often dilation reduced; aedeagus as in Fig. 5N, length 3.8–5.0 mm (Fig. 13); northeastern India ................................................................ P. humeralis (Arrow, 1907)

- Humeral area of elytron without yellow spot, elytra uniformly colored; inner margin of metatibia denticulate with relatively small teeth; metafemoral posterior margin either simple or dilated and produced in a slight angle..................... 15

15 Parameres longer than in next species (Fig. 15A–D); protibia with apical tooth spatulate, bent downward and notably larger than second tooth; first tooth wide, nearly merging with second tooth; metafemoral posterior margin simple, not modified or dilated and produced in slight angle in basal half (Fig. 15); length 3.8–5.0 mm; Indochina...................................................................................................... P. longipenis Tarasov new species

- Parameres shorter than in previous species (Fig. 23A–C); protibia with apical tooth approximately twice as wide as second tooth; first and second teeth distinctly separated from each other; metafemoral posterior margin simple, not modified, sometimes slightly dilated but not produced in angle; length 3.9–5.0 mm (Fig. 23); Indochina..................................................................................................... P. solodovnikovi Tarasov new species

16 Apical spur of protibia equal or longer than first protibial tooth and first three protarsomeres combined (Fig. 7E); inner margin of metatibia not denticulate (Fig. 7G)....................................................................17

- Apical spur of protibia shorter than first protibial tooth and first three protarsomeres combined (Fig. 18E); inner margin of metatibiae with relatively small teeth (Fig. 19F–H).........................................................18

17 Parameres widened basally (lateral view), apex acute; metafemoral posterior margin dilated near middle; dilation widely rimmed (Fig. 7); length 4.2–4.5 mm; southern Laos............................... P. bolavensis Tarasov new species

- Parameres emarginate superiorly (i.e., dorsally in lateral view, Fig. 8A–C), apex rounded; metafemoral posterior margin simple or dilated in apical third, but not rimmed (Fig. 8); length 3.5–4.6 mm; southeastern China, Laos, Vietnam ........................................................................................... P. fukiensis (Balthasar, 1960)

18 Protibia with apical tooth spatulate, bent downward and notably larger than second tooth; first tooth wide, appearing bifurcate as it merges with denticles located between first and second teeth; metafemoral posterior margin simple, not dilated; aedeagus as in Fig. 5H; length 4.8 mm (Fig. 18); Cambodia.......................................... P. nudus (Sharp, 1875)

- Protibia with apical tooth approximately twice as wide as second tooth, first and second teeth distinctly separated from each other; metafemoral posterior margin simple, not modified or slightly dilated in apical forth and produced in rounded angle preapically; aedeagus as in Fig. 5I; length 4.0– 5.5 mm (Fig. 19); Thailand, Malay Peninsula, Sumatra ................................................................................................ P. peninsularis (Arrow, 1907)