Axinoscymnus Kamiya, 1963

Peng, Feng, Xie, Xiufeng, Peng, Zhengqiang, Wang, Xingmin & Chen, Xiaoshen, 2022, A taxonomic review of the genus Axinoscymnus Kamiya, with descriptions of three new species (Coleoptera, Coccinellidae), Zootaxa 5154 (4), pp. 431-453 : 433-435

Genus Axinoscymnus Kamiya, 1963

Axinoscymnus Kamiya, 1963: 127 .

Type species: Axinoscymnus beneficus Kamiya, 1963 , by original designation.

Diagnosis. Axinoscymnus is similar to Sasajiscymnus Vandenberg, 2004 in having three tarsomere tarsi ( Fig. 1d ). It can be also easily distinguished from the other genera belonging to the tribe Scymnini by the following combination of characters: eyes large with a correspondingly narrow frons ( Fig. 1a ); antennae composed of 11 antennomeres ( Fig. 1f ); maxillary palpi weakly securiform ( Fig. 1g ); prosternum in front of procoxae very short ( Fig. 1b ), narrowly carinate, less than half width of procoxal cavity, subtrapezoidal ( Figs 1b–c ); mesoventrite strongly convex ( Fig. 13b ); abdominal postcoxal lines complete ( Fig. 13d ); abdomen with five ventrites ( Fig. 13d ); penis short without penis capsule ( Fig. 13e ), and elongate coxites of female ( Fig. 1j ).

Description. Body oval or elongate oval, moderately convex, dorsum densely pubescent, widest around middle of elytra.

Head transverse; frons relatively narrow ( Fig. 1a ), slightly convex. Eyes large, inner ocular margin arcuate. Clypeus short, anterior margin of clypeus straight. Antennae composed of 11 antennomeres ( Fig. 1f ); antennomere 1 stout, cylindrical, longer than wide; base of the antennomere 2 slightly narrower than antennomere 1, as long as antennomere 1, curved and distinctly rounded on inner side; antennomere 3 relatively slender, base narrowed; antennomeres 4 and 5 subequal to antennomere 3 in length and width; antennomere 6 slightly shorter than antennomere 5; antennomere 7 trapezoidal, apical part wider than base; antennomere 8 to 11 forming a fusiform club, the terminal antennomere small, distinctly narrower and shorter than penultimate one ( Fig. 1f ). Mandible bifid apically, with well-developed molar tooth ( Fig. 1h ). Maxillary palpus with four palpomeres ( Fig. 1g ), the basal one tiny, ring-like, the second one curved, outer margin distinctly longer than inner margin, the third one weakly broadened apically, outer margin twice as long as inner, the terminal palpomere stout, weakly securiform, apical margin weakly obliquely truncate. Labial palps with three palpomeres ( Fig. 1e ), terminal palpomere conical, narrower than penultimate one.

Pronotum moderately convex. Prosternum in front of procoxae very short ( Fig. 1b ), narrowly carinate, less than half width of procoxal cavity, subtrapezoidal ( Figs 1b–c ). Scutellar shield relatively small, triangular ( Fig. 13a ). Elytra at base slightly wider than pronotum, surface finely punctate. Humeri distinct. Lateral margins of elytra weakly arcuate, apex gently rounded. Elytral epipleuron narrow and nearly horizontal, terminated at level of hind coxae. Metaventrite strongly convex ( Fig. 13b ). Abdomen with five ventrites. Abdominal postcoxal lines recurved, complete ( Fig. 13d ).

Legs stout ( Fig. 1d ), not extending beyond external margin of elytra; femora of hind leg broad and flattened; tibiae without apical spurs; tarsus with three tarsomeres, basal and second tarsomeres lobed. Claws with sharp basal tooth.

Male genitalia. relatively simple, penis short and slightly curved at the base, without processes of penis capsule ( Fig. 13e ); tegmen with penis guide and parameres stout and short, penis guide shorter than parameres ( Fig. 13f–g ).

Female genitalia. Coxites elongate, subtriangular, without styli ( Fig. 1j ). Spermatheca short and stout, bulbousshaped as shown on Fig. 1i .

Distribution. Brunei, China, India, Japan, Laos, Nepal, Singapore, Sri Lanka, Vietnam.

Key to the species of the genus Axinoscymnus Kamiya

1. Elytra yellow or pale yellow ( Figs 2a , 3a )................................................................. 2

- Elytra black or dark brown ( Figs 6a , 9a )................................................................... 4

2. Body oval ( Fig. 4a ); abdominal postcoxal lines reaching 1/2 length of ventrite 1 ( Fig. 4d ); penis guide shorter than 1/2 length of parameres ( Fig. 4f )................................................................................. 3

- Body elongate oval ( Fig. 2a ); abdominal postcoxal lines reaching 3/4 length of ventrite 1 ( Fig. 2h ); penis guide slightly shorter than parameres ( Fig. 2j )................................................... Axinoscymnus cardilobus Ren et Pang

3. Body length less than 1.6 mm; apex of penis broadened, knife-shaped ( Fig. 3e ); parameres short and broad in inner view ( Fig. 3g )................................................................ Axinoscymnus apioides Kuznetsov et Ren

- Body length more than 1.9 mm; penis slender with a pointed apex ( Fig. 4e ); parameres long and narrow in inner view ( Fig. 4g ).......................................................... Axinoscymnus gongxinensis Peng et Chen , sp. n.

4. Elytra light brown to dark brown ( Figs 5a , 6a ).............................................................. 5

- Elytra black ( Figs 9a , 12a ).............................................................................. 8

5. Penis slender with a pointed apex........................................................................ 6

- Penis stout with a blunt apex............................................................................ 7

6. Elytra brown without dark markings. Penis guide widest at base in lateral view, then sharply converging to a pointed tip ( Fig. 5f ).................................................................... Axinoscymnus glotticus Ren et Pang

- Elytra yellowish brown with dark brown markings at humeral and apical parts. Penis guide widest at base in lateral view, then gradually converging to a pointed tip.................................................. Axinoscymnus rai Kamiya

7. Elytra dark brown with narrowly apical margin yellowish brown. Abdominal postcoxal line extending to 3/4 length of ventrite 1.......................................................................... Axinoscymnus fumatus (Sicard)

- Elytra dark brown with basal and apical part yellowish brown. Abdominal postcoxal line extending to 1/2 length of ventrite 1................................................................. Axinoscymnus singaporicus Pang et Gordon

8. Basal margin of elytra yellowish brown ( Fig. 7a ).................................. Axinoscymnus beneficus Kamiya

- Basal margin of elytra entirely black ( Fig. 8a ).............................................................. 9

9. Pronotum blackish brown ( Fig. 9a )...................................................................... 10

- Pronotum yellowish brown ( Fig. 11a ).................................................................... 11

10. Head dark brown. Elytra black with a single elongate oval brown spot on each elytron ( Fig. 8a ). Area enclosed by abdominal postcoxal lines semicircular ( Fig. 8d )................................. Axinoscymnus puttarudriahi Kapur et Munshi

- Head black. Elytra black without oval brown spots ( Fig. 9a ). Area enclosed by abdominal postcoxal lines subtriangular ( Fig. 9d )............................................................ Axinoscymnus hamulatus Peng et Chen , sp. n.

11. Central part of pronotum bearing a black or dark brown longitudinal stripe ( Fig. 10a )..................................................................................................... Axinoscymnus navicularis Ren et Pang

- Central part of pronotum without any maculae ( Fig. 11d ).................................................... 12

12. Penis very stout ( Fig. 11h ), strongly broadened at base, apical 1/2 to proximal swollen with membranous appendage............................................................................ Axinoscymnus macrosiphonatus Hoàng

- Penis slender without membranous appendage ( Fig. 12e ), apical part not swollen.................................. 13

13. Ventrite 1 with coarse punctures at middle ( Fig. 12d ); penis guide swollen at base in lateral view ( Fig. 12f ); penis guide parallel sided from base to 3/4, then gradually tapering to pointed tip in inner view ( Fig. 12g ).... Axinoscymnus nigripennis Kamiya

- Ventrite 1 with fine punctures at middle ( Fig. 13d ); penis guide not swollen at base in lateral view ( Fig. 13f ); penis guide triangular in inner view ( Fig. 13g ).................................... Axinoscymnus pingxiangicus Peng et Chen , sp. n.

Figures

FIGURE 1. Main characters of the genus Axinoscymnus Kamiya: a–h Axinoscymnus pingxiangicus Peng et Chen, sp. n.: a head b prothorax, ventral view c prothorax, frontal view d hind leg e labium f antenna g maxilla h mandible i–j Axinoscymnus beneficus Kamiya, 1963: i spermatheca j coxites. Scale bars: 0.1 mm.

FIGURE 2. Axinoscymnus cardilobus Ren et Pang, 1992: d–f holotype a, d dorsal view b, e lateral view c, f frontal view g labels of holotype h abdomen i penis j tegmen, lateral view k tegmen, inner view. Scale bars: a–f: 0.5 mm, h: 0.2 mm, i–k: 0.05 mm.

FIGURE 3. Axinoscymnus apioides Kuznetsov et Ren, 1991: a dorsal view b lateral view c frontal view d abdomen e penis f tegmen, lateral view g tegmen, inner view. Scale bars: a–c: 0.5 mm, d: 0.2 mm, e–g: 0.05 mm.

FIGURE 4. Axinoscymnus gongxinensis Peng et Chen, sp. n.: a dorsal view b lateral view c frontal view d abdomen e penis f tegmen, lateral view g tegmen, inner view. Scale bars: a–c: 0.5 mm, d: 0.2 mm, e–g: 0.1 mm.

FIGURE 5. Axinoscymnus glotticus Ren et Pang, 1992 (Holotype): a dorsal view b lateral view c frontal view d abdomen e penis f tegmen, lateral view g tegmen, inner view h labels of holotype. Scale bars: a–c: 0.5 mm, d: 0.1 mm, e–g: 0.05 mm.

FIGURE 6. Axinoscymnus singaporicus Pang et Gordon, 1986 (Paratype): a dorsal view b ventral view c lateral view d labels of paratype. Scale bars: a–c: 0.5mm.

FIGURE 7. Axinoscymnus beneficus Kamiya, 1963: a dorsal view b lateral view c frontal view d abdomen e penis f tegmen, lateral view g tegmen, inner view. Scale bars: a–c: 0.5 mm, d: 0.1 mm, e–g: 0.05 mm.

FIGURE 8. Axinoscymnus puttarudriahi Kapur et Munshi, 1965: a dorsal view b lateral view c frontal view d abdomen e penis f tegmen, lateral view. Scale bars: a–c: 0.5 mm, d: 0.1 mm, e–f: 0.05 mm.

FIGURE 9. Axinoscymnus hamulatus Peng et Chen, sp. n.: a dorsal view b lateral view c frontal view d abdomen e penis f tegmen, lateral view g tegmen, inner view. Scale bars: a–c: 0.5 mm, d: 0.1 mm, e–g: 0.05 mm.

FIGURE 10. Axinoscymnus navicularis Ren et Pang, 1992: a–c female d–i male g–i holotype a, d, g dorsal view b, e, h lateral view c, f, i frontal view j abdomen k penis l tegmen, lateral view m tegmen, inner view. n labels of holotype. Scale bars: a–i: 0.5 mm, j: 0.1 mm, k–m: 0.05 mm.

FIGURE 11. Axinoscymnus macrosiphonatus Hoàng, 1979: a, d dorsal view b, e lateral view c, f frontal view g abdomen h penis i tegmen, lateral view j tegmen, inner view. Scale bars: a–f: 0.5 mm, g: 0.2 mm, h–j: 0.05 mm.

FIGURE 12. Axinoscymnus nigripennis Kamiya, 1965: a dorsal view b lateral view c frontal view d abdomen e penis f tegmen, lateral view g tegmen, inner view. Scale bars: a–c: 0.5 mm, d: 0.1 mm, e–g: 0.05 mm.

FIGURE 13. Axinoscymnus pingxiangicus Peng et Chen, sp. n.: a dorsal view b lateral view c frontal view d abdomen e penis f tegmen, lateral view g tegmen, inner view. Scale bars: a–c: 0.5 mm, d: 0.1 mm, e–g: 0.05 mm.