Chaetocnema (Chaetocnema) fallaciosa Heikertinger, 1951

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 : 49

11. Chaetocnema (Chaetocnema) fallaciosa Heikertinger, 1951

( Fig. 30 )

Chaetocnema fallaciosa Heikertinger, 1951: 72 . TL: Borneo. TD: NHMB.

Distribution: Malaysia, Indonesia.

Host plants: Unknown.

Description: Body length 1.50–1.70 mm; width 1.10–1.15 mm. Ratio of elytron length at suture to maximum width, 1.80–1.95. Ratio of pronotum width at base to length at middle, 1.90–1.95. Ratio of length of elytron at suture to length of pronotum at middle, 2.55–2.65. Ratio of width of both elytra at base to width of pronotum at base, 1.15–1.20. Ratio of maximum width of both elytra to maximum width of pronotum, 1.40–1.45.

Dorsum black, with slight metallic luster. Antennomeres 1–4 completely yellow. Antennomere 5 partly brown. Tibiae and tarsi yellow. Pro- and mesofemora yellow brown. Metafemur black or dark brown. Head hypognathous. Frontal ridge narrow, convex. Frontolateral sulcus present. Suprafrontal sulcus absent. Ratio of width of frontal ridge between outer ridge of antennal sockets to width of antennal socket, 1.40–1.45. Vertex flat, situated on same level as orbit, without punctures, except 2–3 on each side near eye.

Base of pronotum without longitudinal impressions. Deep row of large punctures at base of pronotum present only laterally. Basal margin of pronotum slightly expanded in middle.

Elytron with scutellar row of punctures single and regular. Second to eleventh rows of elytral punctures regular. Humeral callus well-developed.

Large lateral denticle on metatibia obtuse. Metatibial serration proximal to large lateral denticle absent.

Apex of aedeagus narrowing gradually. Ventral longitudinal groove of aedeagus absent or poorly developed. Apical denticle of aedeagus absent in ventral view. Minute, transverse wrinkles on ventral side of aedeagus absent. Aedeagus in lateral view nearly straight. Maximum curvature of aedeagus in lateral view situated apically.

Types: 1♀ (Holotype) (NHMB), labels: 1) Banguey b. Borneo; 2) fallaciosa m. det. Heiktgr.; 3) fallaciosa Typus; 4) 1935 Coll. Heikertinger; 3♂ 1♀ (Paratypes) (NHMB), labels: 1) Banguey b. Borneo; 2) fallaciosa det. Heiktgr.; 3) fallaciosa Cotypus ; 4) 1935 Coll. Heikertinger.

Material: 21 ( BMNH), Sarawak ( Malaysia): 4 th Division, Gn. Mulu NP., Long Melinau Island , alluvial forest, Malaise trap, nr. Camp 50–100m, P. M. Hammond & J.E.Marshall, v–viii.1978–49, Chaetocnema fallaciosa Heik.,1951 , Det. Yongying Ruan , 2016; 3 ( BMNH), Indonesia: Bomeo Kalimantan Tengah Busang / Rekut confl., 0 03S, 113 59E, Brendell / Mendel, August 2001, General collecting, 2001–191, ‘ Barito Ulu 2001’, BMNH (E), Chaetocnema sp. det. K. Nadein 2007, Chaetocnema fallaciosa Heik.,1951 , Det. Yongying Ruan, 2016.

Remarks: This species closely resembles C. resplendens in the shape of the body. However, it can be distinguished from C. resplendens by the following characters: aedeagus without pointed and acute denticle (present in C. resplendens ), basal margin of pronotum flat (depressed in C. resplendens ), strong punctures occur on lateral sides of basal margin, absent in middle.

Structure of the aedeagus resembles that of C. yiei . However, they obviously differ in many other characters.

Figures

FIGURE 30. Chaetocnema fallaciosa. A Habitus. B Pronotum and peri-scutellar area. C Head, frontal view. D Aedeagus, ventral view. E Aedeagus, lateral view. F Apex of aedeagus, ventral view.