Chaetocnema (Chaetocnema) sticta Maulik, 1926

Ruan, Yongying, Yang, Xingke, Konstantinov, Alexander S., Prathapan, Kaniyarikkal D. & Zhang, Mengna, 2019, Revision of the Oriental Chaetocnema species (Coleoptera, Chrysomelidae, Galerucinae, Alticini), Zootaxa 4699 (1), pp. 1-206 : 102-103

38. Chaetocnema (Chaetocnema) sticta Maulik, 1926

( Fig. 59 )

Chaetocnema sticta Maulik, 1926: 205 . TL: India. TD: BMNH. Lectotype designated here.

Distribution: China (Gansu), India, Myanmar (Tenasserim).

Host plants: Unknown.

Description: Body length: 2.20–2.35 mm. Body width: 1.20–1.30 mm. Ratio of elytron length (along suture) to width (maximum): 2.45–2.50. Ratio of pronotum width (at base) to length: 1.80–1.82. Ratio of length of elytron to length of pronotum (along middle): 2.80–2.85. Ratio of width of elytra at base (in middle of humeral calli) to width of pronotum at base: 1.09–1.12.

Dorsum black with bronzy luster. Dorsum and surface of head not reticulate. Antennae completely yellow brown, with distal antennomeres darker. Tarsi, tibiae, pro- and mesofemora yellow brown. Metafemora brown.

Head hypognathous. Frontal ridge moderately wide, convex. Frontolateral sulcus present. Suprafrontal sulcus present, arched in middle. Orbital, supraantennal sulci deep. Ratio of width of frontal ridge (excluding margin) to width of antennal socket (excluding margin): 1.48–1.52. Vertex with numerous scattered minute punctures. Orbit wide, with 6-8 punctures slightly larger than those on vertex. Frontal ridge with numerous scattered rugged punctures. Number of setae on clypeus: approximately 10. Number of setae on labrum: 6. Anterior margin of labrum slightly concave at middle.

Pronotum without longitudinal impressions near basal margin. Deep row of large punctures at base of pronotum absent. Pronotal base slightly and evenly convex. Lateral margins of pronotum slightly convex, converging forward. Anterolateral prothoracic callosity truncate, moderately developed. Posterolateral prothoracic callosity poorly developed. Diameter of pronotal punctures 1.5–3.5 times smaller than distance between them.

Elytra with slightly convex lateral sides. Elytral punctures distinctly larger than those on pronotum, arranged in single rows, including peri-scutellar row. Elytral interspaces between puncture rows strongly costate at sides, slightly costate at middle. Number of rows of minute punctures on each interspace: 3–4. Humeral callus well developed.

Excavation on metatibia moderately deep. Large lateral denticle on metatibia obtuse. Metatibial serration proximal to large lateral denticle absent or poorly developed.

Apex of aedeagus in ventral view slightly dilated, narrowing abruptly to apical denticle. Ventral longitudinal groove absent. Apical denticle in ventral view minute and acute. Minute transverse wrinkles absent on ventral side. Aedeagus in lateral view evenly curved at middle and base, apical third almost straight. Apical denticle bent ventrally in lateral view.

Spermathecal receptacle flask-shaped. Spermathecal duct coiled. Spermathecal pump much shorter than receptacle, with cylindrical apex. Vaginal palpus slightly narrowing from base to apex, thence approximately parallelsided. Anterior sclerotization of vaginal palpus slightly narrowing anteriorly. Posterior sclerotization longer than wide. Posterior sclerotization wider than anterior.

Types: Lectotype: 1 ( BMNH), 1) Type; 2) Ranikhet, Kumaon, India, H. G. C.; 3) Chaetocnema sticta Mlk., Det. S. Maulik , Type, 1925; 4) examined Ruan Y. Y., 2014; 5 ) Lectotype Chaetocnema sticta Maulik, 1926 Des. Ruan et al., 2016 .

Paralectotypes: 3 ( BMNH), 1) Ranikhet , Kumaon, India, H. G. C.; 2) Chaetocnema sticta Maulik, Cotype, 1925 , Det. S. Maulik; 3) B. M. 1927–92, G. C. Champion; 4 ) Paralectotype Chaetocnema sticta Maulik, 1926 Des. Ruan et al., 2016 .

Paralectotypes: 7 ( BMNH), 1) Bhatkot, Ranikhet, India, H. G. C.; 2) H. G. C. Champion Coll., B. M. 1953–156; 3) Chaetocnema sticta Maulik, Cotype, 1925 , Det. S. Maulik; 4) Ruan Yongying examined, 2014; 5 ) Paralectotype Chaetocnema sticta Maulik, 1926 Des. Ruan et al., 2016 .

Paralectotypes: 2♀ ( BMNH), 1) Ranikhet, Kumaon, H. G. C.; 2) Chaetocnema sticta Maulik, Det. S. Maulik, Cotype, 1925 ; 3) B. M. 1927–92, G. C. Champion; 4) Ruan Yongying examined, 2014; 5 ) Paralectotype Chaetocnema sticta Maulik, 1926 Des. Ruan et al., 2016 .

Materials: Probable materials used for original description by Maulik (1926) (these are uncertain Cotype materials, they are not designated as Paralectotypes here): 3 ( BMNH), 1) Doherty; 2)Tenasserim; 3) Fry Coll., 1905–100; 4) Chaetocnema sticta Maulik, Cotype, 1925 , Det. S. Maulik. 1 ( BMNH), 1) Doherty; Tenasserim; 2) Fry Coll., 1905.100; 3) Chaetocnema sticta Mlk., Cotype, 1923 , Det. S. Maulik.

Remarks: Chaetocnema sticta is rather unique in Oriental Chaetocnema species by the structures on head: numerous extremely minute punctures present through out the frons and vertex; upper part of frontal ridge distinctly wider than lower part.

Figures

FIGURE 59. Chaetocnema sticta. A Lectotype, habitus. B Head, frontal view (Lectotype). C Pygidium (tergite 7) of female (Paralectotype). D Aedeagus (Paralectotype), ventral view. E Aedeagus (Paralectotype), lateral view. F Apex of aedeagus (Paralectotype), ventral view. G Vaginal palpi (Paralectotype). H Spermatheca (Paralectotype). I Tignum (Paralectotype).