Biasticus luteicollis Ha, Truong & Ishikawa, 2022

Ha, Ngoc Linh, Truong, Xuan Lam, Ishikawa, Tadashi, Jaitrong, Weeyawat, Lee, Chi Feng, Chouangthavy, Bounsanong & Eguchi, Katsuyuki, 2022, Three new species of the genus Biasticus Stal, 1867 (Insecta, Heteroptera, Reduviidae, Harpactorinae) from Central Highlands, Vietnam, ZooKeys 1118, pp. 133-180 : 133

Biasticus luteicollis Ha, Truong & Ishikawa sp. nov.

Figs 5C , 6J-N , 19 , 20 , 21

Type material.

Holotype. ♂; HNL2018-025; Vietnam, Dak Lak Province, Chu Yang Sin National Park; 09.v.2018; X. L. Truong leg.; NSMT. Paratypes. 1♀; TXL2016-616; Vietnam, Dak Lak Province, Chu Yang Sin National Park; 05.v.2016; X. L. Truong leg.; IEBR. 1♂; TXL2016-617; Vietnam, Dak Lak Province, Chu Yang Sin National Park; 05.v.2016; X. L. Truong leg.; IEBR. 4♀; HNL2018-078; HNL2018-080; HNL2018-081; HNL2018-082; Vietnam, Gia Lai Province, Kon Chu Rang Nature Reserve; 08.v.2018; X. L. Truong leg.; IEBR. 4♂; HNL2018-079; HNL2018-083; HNL2018-084; HNL2018-085; Vietnam, Gia Lai Province, Kon Chu Rang Nature Reserve; 08.v.2018; X. L. Truong leg.; IEBR. 1♂; HNL2018-086; Vietnam, Gia Lai Province, Kon Chu Rang Nature Reserve; 08.v.2018; X. L. Truong leg.; NSMT. 1♀; HNL2018-017; Vietnam, Dak Lak Province, Chu Yang Sin National Park; 09.v.2018; X. L. Truong leg.; VNMN. 3♀; HNL2018-018; HNL2018-019; HNL2018-020; Vietnam, Dak Lak Province, Chu Yang Sin National Park; 09.v.2018; X. L. Truong leg.; IEBR. 3♀; HNL2018-021; HNL2018-023; HNL2018-024; Vietnam, Dak Lak Province, Chu Yang Sin National Park; 09.v.2018; X. L. Truong leg.; NSMT. 1♂; HNL2018-022; Vietnam, Dak Lak Province, Chu Yang Sin National Park; 09.v.2018; X. L. Truong leg.; NSMT.

Diagnosis.

Body shiny luteous; first visible labial segment and base of second visible labial segment luteous; apical 2/3 of second visible labial segment to third visible labial segment yellowish brown or brown; posterior pronotal lobe luteous; scutellum dark brown in basal half and luteous in apical half, with median pale brownish luteous portion; femora luteous with dark brown or yellowish brown suffusions at apex and sometimes at middle.

This species is most similar to Biasticus flavus (Distant, 1903) in general appearance, especially in coloration and color pattern of the pronotum, scutellum, and abdomen. However, the new species can be easily separated from the latter by a combination of the following characters: femora luteous with some dark brown or yellowish brown suffusions at apex and sometimes at middle (in B. flavus uniformly blackish brown) and abdominal sternites luteous without blackish brown or black suffusion (in B. flavus abdominal sternites luteous with blackish brown or black segmental transverse stripes laterally).

Description.

Male description. Coloration. Body shiny luteous. Head dorsum, except antenniferous tubercle and neck, black; clypeus, antenniferous tubercle, and labrum brown; maxillary plate, gena, and head venter (except anterior margin of maxillary plate and anterior margin of gena) pale yellowish brown; anterior margin of maxillary plate and anterior margin of gena yellowish brown; first visible labial segment and base of second visible labial segment luteous; apical two-thirds of second visible labial segment to third visible labial segment yellowish brown or brown; a luteous suffusion present above upper margin of compound eye; a luteous stripe running along dorsal margin of compound eye and between postero-upper corner of compound eye and ocellus; area around lateral ocellus with yellowish brown suffusion; a longitudinally elongated luteous suffusion present between lateral ocelli; neck yellowish brown. Scape, except base, yellowish brown; base of scape blackish brown; pedicel, first and second flagellomeres dark brown. Collar, anterolateral angle, and posterior pronotal lobe pale luteous; anterior pronotal lobe, except lateral margin, shiny dark brown, sometimes with luteous suffusion centrally; lateral margin of anterior pronotal lobe, acetabulum, thoracic sterna, stridulatory sulcus, coxae, and trochanters pale luteous; coxae and trochanters sometimes with dark brown or yellowish brown spots; pleura, except lower half of propleuron, dark brown; lower half of propleuron pale luteous; scutellum dark brown in basal half and luteous in apical half, with median pale brownish luteous portion; femora luteous; fore femora apically dark brown, sometimes with dark brown or yellowish brown suffusion; mid and hind femora apically and medially yellowish brown; tibiae dark brown. Corium and clavus yellow or brownish yellow; membrane bronzy brown, semi-hyaline. Hind wings faintly semi-hyaline. Abdominal mediotergites, except posterior half of mediotergite VII, brownish yellow; posterior half of mediotergite VII luteous; abdominal sternites pale luteous; connexivum pale luteous, with segmentally dark brown suffusions. Pygophore ventrally luteous; paramere semi-hyaline, luteous.

Structure. Body medium-sized (BL = 9.19-10.21 mm), elongate, and somewhat robust. Head subelongate and robust (HL/PoW = 2.35-2.48), as long as or a little shorter than pronotum (HL/PnL = 0.84-1.03); postocular area of head sub-globose (PoL/PoW = 0.77-0.93), distinctly wider than anteocular area (PoW/AoW = 1.36-1.43), nearly as long as anteocular area (PoL/AoL = 0.84-1.03), constricted behind compound eyes, with a wide and deep interocular sulcus; neck short. Compound eyes protruding laterally, nearly globose, with posterior margin sub-straight and sometimes concave; lateral ocelli produced, elevated behind interocular sulcus, widely separated from each other (OCD/PoW = 0.42-0.48); interspace between lateral ocelli wider than distance between compound eye and lateral ocellus (OCD/COD = 1.95-2.36). First visible labial segment shorter than second segment (R1L/R2L = 0.79-0.82), longer than anteocular area of head (R1L/AoL = 1.39-1.51), not extending beyond level of middle of compound eye when labium laid backward; proportional average length of first to third visible labial segments 1.1:1.3:0.4. Scape ~ 1.4 × as long as head; pedicel slightly shorter than first flagellomere and nearly 0.7 × as long as second flagellomere; proportional average length of scape, pedicel, first and second flagellomeres 2.9:1.4:1.5:2.0. Collar very thick in dorsal view, with anterolateral angle roundly produced laterad; anterior pronotal lobe round and bulged, slightly rough, with middle longitudinal sulcus deep and narrow posteriorly; posterior pronotal lobe shallowly depressed on disc, abundantly punctured, with slightly swollen anteromedial elevation (never sulcate or concave); humerus roughly triangular, with round apex; posterior margin of pronotum concave; posterior angles round, slightly exceeded to posterior margin of pronotum. Scutellum triangular, somewhat triangularly depressed basally, apically produced and sloping downward; posterior apex round; anterior margin slightly convex. Femora thick, apically moderately nodulose; fore femora very slightly incrassated, thicker than mid and hind femora. Hemelytra surpassing beyond apex of abdomen when fully closed, 0.8 × as long as body length; discal cell nearly parallelogram-shaped, twice as long as width; Sc 0.8 × as long as hemelytron length, 1.5 × as long as R + M. Hind wing ~ 3.3 × as long as maximum width. Connexivum slightly dilated and ascending with segmental incisures; pygophore ovoid; median process of pygophore (mpp) broad and low, 0.2 × as long as wide, with apical margin weakly and continuously convex, and with apicolateral corner slightly produced laterad and pointed; paramere long, slender, clavate, somewhat curved medially, and apically subnodulose and round (Figs 6J , 21B-E ). Aedeagus in dorsal view ovoid, dorsally sclerotized (Figs 6K , 21F ) and in lateral view long and narrow (Figs 6L , 21G ); articulatory apparatus (aa) in ventral view with relatively broad basal plates jointly forming a V-shape, and in lateral view arched moderately (Figs 6L, N , 21G, I ); dorsal phallothecal sclerite (dps) in lateral view with posteromedian part strongly produced posterodorsad (Figs 6L , 21G ); spoon-like sclerites (sps) semi-hyaline and covered with tiny blunt prickles; both membranous sac-like lobes laterally produced; distal dorsal lobe of endosoma (ddl) round, with membranous surface covered with small but distinct prickles (Figs 6M , 21J ).

Vestiture. Body clothed with cream-yellow setation. Head dorsum (except antenniferous tubercle, posterior base of clypeus, and gena) covered with short thick erect setae; area around antenniferous tubercle, posterior margin of clypeus, head venter, and lateral area of postocular area of head covered with short bent pubescence; head venter somewhat with a few long bent setae; maxillary plate without setae; first visible labial segment basally covered with a few erect setae; second and third visible labial segments without setae; scape with a few tiny erect setae; pedicel, first and second flagellomeres densely covered with short slender oblique setae. Anterior margin of collar densely covered with very short erect setae; dorsum of collar with bent cream-yellow pubescence; anterolateral angle and lateral region of collar with long thick erect setae, one of them placed at tip of anterolateral angle; pronotum and scutellum with long thick erect setae; lateral region of slopes of scutellum covered with long slender bent setae; posterior apex of scutellum with a pinch of long slender bent setae and long thick vertical setae; prosternum, except posterior margin, covered with long thick erect setae; posterior margin of prosternum, meso- and metasterna, pleura, and coxae abundantly covered with short bent pubescence. Corium densely covered with bent setae along anterior margin, centrally covered with short slender oblique setae. Abdomen sometimes with erect setae, slightly denser in posterior margin of abdomen; anterior margin of mediotergite I+II, anterior margin of sternite II, and lateral region of laterotergite II with very long slender erect setae; pygophore posteroventrally with some long erect setae and some bent slender setae; paramere with long thick erect setae.

Female description. General external morphology similar to that of the male.

Coloration. Almost similar to male but slightly darker than male. Abdominal mediotergites, except posterior half of mediotergite VII, dark brown and darker backward; posterior half of mediotergite VII luteous; external genitalia pale luteous.

Structure. Almost similar to male but slightly larger than male. Body medium-sized (BL = 10.11-10.91 mm). Proportional average length of first to third visible labial segments 1.1:1.4:0.4. Scape ~ 1.3 × as long as head; pedicel ~ as long as first flagellomere and ~ 0.8 × as long as second flagellomere; proportional average length of scape, pedicel, first and second flagellomeres 2.7:1.3:1.3:1.7. Sc 0.8 × as long as hemelytron length, and 1.5 × as long as R + M. Hind wing ~ 3.1 × as long as maximum width. Abdominal laterotergite VIII (AL8) with very thick posterior margin (0.09 mm); abdominal sternite VII (AS7) forming a wide subrectangular concavity, with posteromedian margin almost straight, with inner posterolateral margin weakly sinuous; gonocoxa VIII (Gc8) broad, ~ 1.2 × wider than length, slightly opened inward for gonapophyses VIII (Gp8), sinuate along outer lateral margin, almost horizontal or weakly sinuate along posterior margin, weakly produced posteromesad and forming a blunt apex at apical inner corner, and with inner margin strongly incurved in its posterior 2/3; Gp8 small and subtriangular, ~ 3 × longer than width; gonoplac (Gpl) V-shaped, with maximum thick ~ 0.05 mm.

Vestiture. Almost similar to male. Abdominal laterotergite VIII (AL8) and tergite IX (AT9) with some long thick erect setae and with shorter setae; apex of abdomen with some very long thick erect setae.

Measurements.

All dimensions are given in mm. Holotype (♂): BL 9.29; HL 2.01; AoL 0.75; AoW 0.60; PoL 0.62; PoW 0.81; OE 1.12; IE 0.58; ED 0.63; OD 0.16; OCD 0.35; COD 0.18; R1L 1.03; R2L 1.30; R3L 0.32; A1L 2.85; A2L 1.41; A3L 1.55; A4L 2.07; PnL 2.21; PnW 2.64; APL 0.90; PPL 1.31; HeL 7.26; HeW 2.47; Sc 5.66; R+M 3.84; HWL 4.92; HWW 1.54; AFL 3.33; ATL 3.87; MFL 2.46; MTL 3.24; PFL 3.58; PTL 4.84. Paratypes (♂): BL 9.19-10.45; HL 1.94-2.12; AoL 0.70-0.79; AoW 0.57-0.62; PoL 0.64-0.77; PoW 0.80-0.86; OE 1.08-1.17; IE 0.55-0.59; ED 0.60-0.64; OD 0.14-0.19; OCD 0.34-0.41; COD 0.15-0.18; R1L 1.03-1.14; R2L 1.26-1.41; R3L 0.32-0.46; A1L 2.68-3.06; A2L 1.30-1.55; A3L 1.37-1.61; A4L 1.74-2.17; PnL 1.95-3.10; PnW 2.42-2.74; APL 0.74-0.99; PPL 1.22-2.25; HeL 7.26-7.88; HeW 2.23-2.63; Sc 5.32-6.09; R+M 3.44-4.08; HWL 4.92-5.22; HWW 1.46-1.62; AFL 3.15-3.46; ATL 3.78-4.08; MFL 2.33-2.69; MTL 2.73-3.50; PFL 3.56-3.91; PTL 4.80-5.10. Paratypes (♀): BL 10.11-10.91; HL 2.00-2.10; AoL 0.73-0.79; AoW 0.60-0.63; PoL 0.67-0.76; PoW 0.82-0.87; OE 1.06-1.15; IE 0.55-0.60; ED 0.59-0.63; OD 0.15-0.19; OCD 0.36-0.46; COD 0.18-0.20; R1L 1.08-1.15; R2L 1.31-1.41; R3L 0.32-0.37; A1L 2.52-2.83; A2L 1.26-1.35; A3L 1.23-1.41; A4L 1.61-1.87; PnL 2.09-2.47; PnW 2.24-3.65; APL 0.70-0.88; PPL 1.39-1.65; HeL 7.66-8.21; HeW 2.60-2.92; Sc 5.86-6.32; R+M 4.01-4.45; HWL 5.25-6.82; HWW 1.67-2.15; AFL 3.00-3.33; ATL 3.63-4.07; MFL 2.31-3.13; MTL 2.94-3.83; PFL 3.33-3.80; PTL 4.61-5.13.

Distribution.

Vietnam, Central Highlands (Dak Lak, Gia Lai).

Type locality.

Vietnam, Central Highlands, Dak Lak Province, Chu Yang Sin National Park.

Etymology.

The new species is named after its yellow posterior pronotal lobe.

Figures

Figure 5. Female external genitalia of six morphospecies in ventral view A type fA, Biasticus taynguyenensis Ha, Truong & Ishikawa, sp. nov., holotype, ♀, HNL 2018 - 073 B type fB, B. griseocapillus Ha, Truong & Ishikawa, sp. nov., holotype, ♀, HNL 2018 - 038 C type fC, B. luteicollis Ha, Truong & Ishikawa, sp. nov., paratype, ♀, HNL 2018 - 024 D type fD, B. flavinotus (Matsumura, 1913), ♀, HNL 2018 - 117 E type fE, B. confusus Hsiao et al., 1979, ♀, VN-Hem- 1998 - 012 F type fF, B. flavus (Distant, 1903), ♀, LA-Redu- 2004 - 006.

Figure 6. Male genitalia of four morphospecies A-D type mA, Biasticus taynguyenensis Ha, Truong & Ishikawa, sp. nov., paratype, ♂, TXL 2016 - 545 E-I type mB, B. griseocapillus Ha, Truong & Ishikawa, sp. nov., paratype, ♂, TXL 2016 - 546 J-N type mC, B. luteicollis Ha, Truong & Ishikawa, sp. nov., holotype, ♂, HNL 2018 - 025 O-R mF, B. flavus (Distant, 1903), ♂, HEM-TH 2004 - 018. A, E, J, O pygophore with paramere (s) in dorsal view B, F, K, P phallus in dorsal view C, G, L, Q phallus in lateral view D, I, N, R articulatory apparatus H, M distal dorsal lobe of endosoma.

Figure 19. Biasticus luteicollis Ha, Truong & Ishikawa, sp. nov., holotype, ♂, HNL 2018 - 025 A body in dorsal view B body in lateral view C head in dorsal view D head in lateral view.

Figure 20. Biasticus luteicollis Ha, Truong & Ishikawa, sp. nov., holotype, ♂, HNL 2018 - 025 A pronotum in dorsal view B anterior pronotal lobe in dorsal view C setae on posterior pronotum D right hemelytron E right hind wing.

Figure 21. Biasticus luteicollis Ha, Truong & Ishikawa, sp. nov. A female external genitalia in ventral view, paratype, ♀, HNL 2018 - 024 B-J male genitalia, holoype, ♂, HNL 2018 - 025 B-E pygophore with parameres B dorsal view C lateral view D ventral view E apical portion of pygophore, showing median process (mpp) and parameres F-H phallus F phallus with endosoma semi-everted, dorsal view G phallus with endosoma semi-everted, lateral view H phallus with endosoma semi-everted, ventral view I articulatory apparatus (aa) J distal dorsal lobe of endosoma (ddl).