Chaetocnema (Chaetocnema) malaisei Bryant, 1939

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 : 74-75

24. Chaetocnema (Chaetocnema) malaisei Bryant, 1939

( Fig. 45 )

Chaetocnema malaisei Bryant, 1939: 16 . TL: Myanmar. TD: BMNH.

Distribution: Myanmar.

Host plants: Unknown.

Description: Body length 1.80–2.00 mm, body width 1.10–1.15 mm. Ratio of elytron length (along suture) to width (maximum): 2.30–2.40. Ratio of length of elytron to length of pronotum (along middle): 2.40–2.50. Ratio of width of elytra at base to width of pronotum at base (in middle of humeral calli): 1.10–1.20. Ratio of maximum width of elytra to maximum width of pronotum: 1.30–1.40.

Elytra and pronotum black, without metallic luster. Antennomere 1 partially dark brown, 2–4 completely yellow, 5 partially brown, 6–11 brown. Tibiae partially brown. Pro- and mesofemora light brown, metafemora brown.

Head hypognathous. Frontal ridge narrow, convex. Frontolateral sulcus present. Suprafrontal sulcus relatively deep, well recognized. Suprafrontal sulcus straight to shallowly retuse. Ratio of width of frontal ridge to width of antennal socket: 1.10–1.30. Frons with long setae on sides. Vertex flat, situated on same level as orbit. Surface of vertex with 3–5 punctures on each side near eye.

Pronotum with two short indistinct longitudinal impressions visible near basal margin. Deep row of large punctures at base of pronotum absent. Pronotal base evenly convex. Area adjacent to mid basal margin of pronotum covered with punctures. Surface of pronotum near base without shallow transverse impression. Lateral margins of pronotum slightly convex, converging forward. Anterolateral prothoracic callosity protruding laterally, moderately developed. Posterolateral prothoracic callosity poorly developed. Diameter of pronotal punctures subequal to distance between them.

Elytra with convex lateral sides, scutellar row of elytral punctures regular and single. Second to eleventh rows of punctures regular. Humeral callus well developed.

First and second male protarsomeres, length to length ratio: 1.50–1.60. Excavation on tibiae moderately developed. Large lateral denticle on metatibia obtuse. Metatibial serration proximal to large lateral denticle present, obtuse. Metatibia proximal to denticle in dorsal view convex.

Type: 1 female (Cotype) ( BMNH), 1) N. E. Burma, Kambaiti , 7000ft, 5/4 1939, R. Malaise; 2) Cotype; 3) N. E. Burma: R. Malaise, B.M. 1939–101; 4) Chaetocnema malaisei Bryant, Det. G. E. Bryant ; 5) examined Ruan Y. Y., 2014 .

Remarks: This species is close to C. cheni , however, it differs from the latter by the darker appendages and entirely black elytra without conspicuous metallic luster.

Figures

FIGURE 45. Chaetocnema malaisei. A Male habitus (Cotype). B Pronotum (Cotype). C Head, frontal view (Cotype).