Thoradonta lativertexoides Zha and Kang, sp. nov.

Thoradonta lativertexoides Zha and Kang sp. nov.

(Figures 1A, B, 2A–D)

Body size small, covered with numerous small granules and many nodules (Figure 1A, B). Head not protruding over level of pronotal surface; vertex about 2.0 times one eye in width, anterior margin straight, protruding forwards to same level of anterior margins of eyes, lateral margins folded upwards but not surpassing beyond top of eyes (Figures 1B, 2B); median carina conspicuous and protruding in anterior half, which is visible before eyes in profile, while obscure or absent in posterior half; vertex and frontal ridge roundly protruding, excessively concave between lateral ocelli, and then excessively protruding in an arch-like manner between antennae, longitudinal furrow slightly wider than first segment of antenna in width (Figure 2A). Antenna filiform, 15-segmented, inserted slightly below lower margins of eyes, length of longest segment (segment IV) about six times its width. Eyes globose, protruding but not above level of pronotum (Figure 2B); lateral ocellus situated slightly below middle of anterior margin of eye (Figure 2A). Pronotum very coarse, covered with numerous small granules and many nodules; anterior margin straight, lateral keels erected, contracted backward, sometimes undulate in lateral view. Mid-keel not reaching anterior margin of pronotum, interrupted before shoulders, in profile upper margin distinctly undulate. These sinusoidal waves lamellate and erected, first highest, with intumesced base, both sides of intumescence with a pair of big nodules at margins of pronotum; second lamella very short and low; third lamella longest and undulate, its peak nearly of same height as first; on both sides pronotal disc distinctly concave followed by a pair of long oblique nodules, and lateral margins of pronotum distinctly folded upwards; the latter lamellae becoming lower backward and disappearing on distal part, three or four lamellae are visible and they connect with nodules of both their sides, respectively (Figure 1A, B). Humeral angle obtuse, with a pair of abbreviated carinae between shoulders, pronotum slightly uplifted between shoulders (Figure 1B); hind process of pronotum long cone-shaped, nearly reaching top of hind tibia, apex truncate (Figure 1A, B); posterior angles of lateral lobes of pronotum extending outwards, distal part slightly oblique backward, fore margin of posterior angle smooth while hind margin with small teeth, apex spine-like; posterior margin of each lateral lobe with two concavities. Tegmina ovate, 2.2 times as long as wide, apex rounded. Hindwing surpassing slightly beyond top of hind process of pronotum. Upper and lower margins of fore and mid femora undulate, with fine teeth; width of basal mid femur slightly wider than width of tegmen, middle femur distinctly narrowed from basal to distal side, and basal part thicker than distal part. Hind femur about 2.6 times as long as wide, upper and lower margins dentate, outer side and upper side with a series of nodules respectively; upper margin with a triangular protrusion before antegenicular, antegenicular isolated and long triangular, its apex nearly rightangled, genicular denticle fingered extending backward and apex triangular (Figure 2D). Width of distal hind tibia slightly wider than basal, outer side with four to six spines, inner side with four spines; first segment of hind tarsus about 1.3 times longer than third, third pulvillus longer than first and second, apices of all pulvilli sharp. Subgenital plate short cone-shaped (Figure 2C), apex bifurcate and bidentate.

Body dark brown. Antenna brown and colour of distal segments darker; hindwings black; fore and mid femora and tibiae with three yellowish brown bands, bands of femora obscure; lower outside of hind femur black, centre of inner side of hind femur dark brown; hind tibia with two long yellowish brown bands.

Unknown.

Length of body (mm): ♂ 6.0–6.8; length of pronotum: ♂ 7.7–8.2; length of hind femur: ♂ 4.0–4.2.

Holotype (No. 15-0642, MFLU): ♂, Thailand, Chiang Rai, Doi Thong (19°47 ′ 58 ′′ N, 99°33 ′ 13 ′′ E, 1234.7 m altitude), 8 November 2014, collected by ZHA Ling-Sheng. Paratypes: 1♂ (No. 15-0643, MFLU) and 1♂ (HNU), same data as holotype.

Thoradonta lativertexoides sp. nov. is similar to T. lativertex Günther, 1938, but it differs in: (1) antenna inserted decidedly below lower margins of eyes (Figure 2A); (2) lateral keels distinctly contracted backward (Figure 1B); (3) a short and lower lamellate protrusion present between two highest lamellate protrusions on mid-keel, mid-keel interrupted before this short protrusion (Figure 1B); (4) humeral angle obtuse angled (Figure 1B); (5) upper margin of hind femur with a triangular protrusion before antegenicular, antegenicular isolated and long triangular (Figure 2D).

The new species epithet is derived from Thoradonta lativertex, which means it is similar to that species.

Thailand (Chiang Rai).