Macrolycus acutiapex Y. Yang, Liu & X. Yang, 2025

Macrolycus acutiapex Y. Yang, Liu & X. Yang sp. nov.

urn:lsid:zoobank.org:act:28C36CE6-34D4-4FBE-84A8-0151F8ACF9DC

Figs 1 View Fig , 3J–L View Fig , 4F View Fig

Diagnosis

This species can be distinguished from the remaining species of the M. gracilis group by the antennomere III with slender and short lamella, 0.7 × as long as joint itself. It is more similar to M. mucronatus Li, Bocak & Pang, 2012 , but can be differentiated by the antennomere III with slender lamella, 0.7 × as long as joint itself; apical part of the phallus gradually narrowed distad in ventral view ( Fig. 3K View Fig ), and subapical part inflated ventrally in lateral view ( Fig. 3L View Fig ). Unlikely, in M. mucronatus , the antennomere III is stouter, with lamella about half length of joint itself; apical part of the phallus is abruptly narrowed distad in ventral view ( Li et al., 2012: fig. 38), and subapical part flat in lateral view ( Li et al., 2012: fig. 37).

Etymology

The specific epithet is derived from the Latin ‘ acutus ’ (‘sharp’) and ‘apex ’ (‘tip’), referring to its lamella of antennomere III with pointed apex.

Type material

Holotype

CHINA • ♂; Hubei, Xingshan, Longmenhe ; 2200 m a.s.l.; 13 Jun. 1995; S.Y. Wang leg.; IOZ(E)1119901; IZAS.

Description

Male ( Fig. 4F View Fig )

MEASUREMENTS. Length 7.3 mm, width at humeri 1.6 mm.

HABITUS AND COLORATION. Body black brown. Pronotum, elytra and scutellum dark red. Elytral costae IV orange-red. Surface covered with decumbent red pubescence.

HEAD. Eyes small, interocular distance about 1.7 × as long as eye diameter. Antennae flabellate, overlapping basal ⅔ length of elytra when inclined. Antennomeres III‒XI lamellate, lamellae pointed at apices, lamella of III extremely slender, about 0.7 × as long as joint itself, lamella of IX longest, 4.2× as long as joint itself ( Fig. 4F View Fig ).

PRONOTUM. Trapezoidal, 1.3 × as wide as long. Anterior margin widely rounded, lateral margins obviously sinuate and posterior margin nearly straight; anterior angles confluent with anterior margin, posterior angles sharp and moderately projected. Scutellum trapezoidal, nearly straight at apex ( Fig. 4F View Fig ).

ELYTRA. Slender and subparallel-sided, 3.9 × as long as humeral width. Costae I and III weak but visible at whole length, costa IV weaker than II and both separated at apical part of elytra ( Fig. 4F View Fig ).

AEDEAGUS. Phallus slender, with basal part narrowed to middle in dorsal and ventral views ( Fig. 3J–K View Fig ), subapical part strongly and almost symmetrically inflated laterally, about 1.67× as wide as basal part, with an oval ventral-cavity, apical part gradually narrowed distad, apex about 0.25× as wide as subapical part; curved ventrally at basal 5 /16 portion, and bent dorsally at apical 7 /16 portion in lateral view ( Fig. 3L View Fig ), subapical part feebly inflated ventrally, apical part nearly straight and flat ventrally.

Female

Unknown.

Distribution

China (Hubei).

Key to the species of the Macrolycus gracilis group

1. Antennomere III lamellate in male, lamella at least 0.7 × as long as joint itself (e.g., Fig. 4D, F View Fig ; Li 2015: fig. 3e) ..................................................................................................................................... 2

– Antennomere III triangular or cylindrical in male, without any lamella (e.g., Fig. 4A, C View Fig ; Kazantsev 2001: fig. 8; 2002: fig. 9; Li et al. 2012: figs 50–51; 2015: figs 2–6) ............................................... 4

2. Pronotum black ( Fig. 4D View Fig ); phallus with apical part slightly bent dorsally in lateral view ( Fig. 3F View Fig ) .. ..................................................................................................................... M. graciliramus sp. nov.

– Pronotum dark red or orange (e.g., Fig. 4F View Fig ; Li 2015: fig. 3e); phallus with apical part straight in lateral view (e.g., Fig. 4L View Fig ; Li 2015: fig. 10e) .................................................................................... 3

3. Lamella of antennomere III as long as joint itself (Li 2015: fig. 7u); apical part of phallus parallel-sided in ventral view (Li 2015: fig. 10f) ............................................................ M. gracilis Pic, 1923

– Lamella of antennomere III 0.7× as long as joint itself ( Fig. 4F View Fig ); apical part of phallus narrowed distad in ventral view ( Fig. 4K View Fig ) ........................................................................ M. acutiapex sp. nov.

4. Antennomere III cylindrical in male ( Fig. 4C View Fig ); basal part of phallus obviously asymmetrical, expanded to one side in ventral view ( Fig. 3H View Fig ) ............................................. M. breviramus sp. nov.

– Antennomere III triangular in male (e.g., Fig. 4A View Fig ; Kazantsev 2001: fig. 8; 2002: fig. 9; Li et al. 2012: figs 50–51; 2015: figs 2–6); basal part of phallus nearly symmetrical (e.g., Fig. 3B View Fig ; Kazantsev 2001: fig. 9; 2002: fig. 10; Li et al. 2012: figs 38, 40; 2015: figs 15, 17, 19, 21, 23) ................................. 5

5. Apical part of phallus moderately inflated distad in ventral view ( Li et al. 2015: fig. 15) ................ ...................................................................................... M. baihualingensis Li, Bocak & Pang, 2015

– Apical part of phallus narrowed distad in ventral view (e.g., Fig. 3B View Fig ; Kazantsev 2001: fig. 9; 2002: fig. 10; Li et al. 2012: figs 38, 40; 2015: figs 17, 19, 21, 23) ........................................................... 6

6. Pronotum black ( Fig. 4A View Fig ); subapical part of phallus moderately inflated ventrally in lateral view ( Fig. 3C View Fig ) ........................................................................................................... M. nigricollis sp. nov.

– Pronotum dark red or orange; subapical part of phallus flat ventrally in lateral view (e.g., Kazantsev 2001: fig. 10; 2002: fig. 11; Li et al. 2012: figs 37, 39; 2015: figs 16, 18, 20, 22) ........................... 7

7. Phallus with apical part curved dorsally in lateral view (e.g., Li et al. 2015: figs 20, 22) ............... 8

– Phallus with apical part straight in lateral view (e.g., Kazantsev 2001: fig. 10; 2002: fig. 11; Li et al. 2012: figs 37, 39; 2015: figs 16, 18) ................................................................................................. 9

8. Elytral costa II orange-red; phallus with basal part narrowed to middle in ventral view ( Li et al. 2015: fig. 21), and apical part moderately curved dorsally in lateral view ( Li et al. 2015: fig. 20) ............................................................................... M. rhodoneurus Li, Bocak & Pang, 2015

– Elytral costa II dark red; phallus with basal part parallel-sided in ventral view ( Li et al. 2015: fig. 23), and apical part strongly curved dorsally in lateral view ( Li et al. 2015: fig. 22) ............................... .................................................................................................. M. rosaceus Li, Bocak & Pang, 2015

9. Phallus with apical part gradually narrowed distad (e.g., Kazantsev 2001: fig. 9; 2002: fig. 10; Li et al. 2015: fig. 19) .......................................................................................................................... 10

– Phallus with apical part abruptly narrowed distad (e.g., Li et al. 2012: figs 38, 40; Li et al. 2015: fig. 17) ............................................................................................................................................. 12

10. Pronotum and elytra orange; apex of phallus about ¼ as wide as subapical part ( Kazantsev 2001: fig. 9) ............................................................................................... M. aurantiacus Kazantsev, 2001

– Pronotum and elytra dark red (e.g., Li et al. 2015: fig. 4); apex of phallus at most 1 /5 as wide as subapical part (e.g., Kazantsev 2002: fig. 10; Li et al. 2015: fig. 19) ..............................................11

11. Pronotum and elytra orange red ( Li et al. 2015: fig. 4); basal part of phallus uneven in width in ventral view ( Li et al. 2015: fig. 19); apical part moderately inflated ventrally near apex in lateral view ( Li et al. 2015: fig. 18) ............................................... M. phoeniceus Li, Bocak & Pang, 2015

– Pronotum and elytra dark red; basal part of phallus parallel-sided in ventral view ( Kazantsev 2002: fig. 10), apical part flat ventrally in lateral view ( Kazantsev 2002: fig. 11) ....................................... ....................................................................................................... M. multicostatus Kazantsev, 2002

12. Phallus with apical part abruptly narrowed distad in lateral view ( Li et al. 2015: fig. 16) ................ ............................................................................................ M. lizipingensis Li, Bocak & Pang, 2015

– Phallus with apical part nearly parallel-sided in lateral view (e.g., Li et al. 2012: figs 37, 39) ..... 13

13. Antennae relatively long, overlapping basal 4 /5 length of elytra when inclined ( Li et al. 2012: fig. 50); phallus bent dorsally at basal ⅓ portion in lateral view ( Li et al. 2012: fig. 37) ................................ ............................................................................................ M. mucronatus Li, Bocak & Pang, 2012

– Antennae relatively short, overlapping basal ½ length of elytra when inclined ( Li et al. 2012: fig. 51); phallus bent dorsally at basal 1 /6 portion in lateral view ( Li et al. 2012: fig. 39) ............................... .............................................................................................. M. muyuensis Li, Bocak & Pang, 2012