Agonischius yokoyamai, Arimoto, Kôichi, 2016

Arimoto, Kôichi, 2016, Taxonomic notes on three species of the genus Agonischius (Coleoptera, Elateridae, Elaterinae, Elaterini) with a new species from Taiwan, Zootaxa 4114 (2), pp. 149-161 : 150-154

Agonischius yokoyamai sp. nov.

( Figures 1–27 )

Type material. Holotype: male, Meifeng, Renai Township, Nantou County, Taiwan, 14/VI/1974, H. Yokoyama leg. ( OMNH). Paratypes (14 males, 4 females): 1 male, Ruisui Township, Hualien County, Taiwan, 15/V/1972, H. Yokoyama leg. ( OMNH); 8 males, 2 females, same place and collector as the former 15/VI/1972 ( OMNH); 4 males, 1 female, same place and collector as the former, 19/VI/1972 ( OMNH); 1 male, same place and collector as the former, 20/VI/1972 ( OMNH); 1 female, Huitouwan to Tianxiang (about 5 km section on Route 8), 1020– 710m, Xiulin Township, Hualien County, Taiwan, 15–16/VIII/1989, M. Ôhara leg. ( HUM).

Distribution ( Fig. 1 ). Taiwan (Nantou-county, Hualien-county).

Description. Adults. Measurements. Male [holotype]. BL: 9.01–10.5 [10.3], BW: 2.55–3.04 [2.94], PL: 2.24– 2.61 [2.43], PML: 1.95–2.31 [2.13], PW: 2.48–3.02 [2.86], PL/PW: 0.850–0.903 [0.850], EL: 6.51–7.56 [7.37], EW: 2.55–3.04 [2.94], EL/EW: 2.49–2.55 [2.51]. Female. BL: 11.3–12.4, BW: 3.17–3.62, PL: 2.83–3.14, PML: 2.44–2.78; PW: 3.11–3.54, PL/PW: 0.887–0.910, EL: 8.02–8.98, EW: 3.17–3.62, EL/EW: 2.48–2.53.

Body ( Figs. 2, 3 ) elongate; surface smooth, shining, covered with yellowish brown setae. Color. Uniformly dark orang to brown; elytra paler; external margin of mandible, pronotal posterior margin, external margin of scutellum, elytral anterior margin, external margin of prosternum and hypomeron black or nearly black.

Head short, convex; frontal margin not carinate, truncated transversely, without nasal plate ( Fig. 5 ); punctures umbilicate and coarse. Labrum ( Fig. 7 ) wide semicircular, with sparse long setae. Antennae long and exceeding apices of pronotal posterior angles by apical three segments in male ( Fig. 8 ), moderate and just reaching apices of posterior angles by apical segment in female ( Fig. 9 ); segment II globular, shortest; segment III conical, shorter than segment IV; segments IV–X almost same length as each other, long serrate in male, short fan-shaped in female; segment XI longest. Mandibles ( Fig. 10 ) with subapical teeth; penicillum well developed, formed by dense brush of short setae; dorsal sinuous carina well developed; with setae of various lengths on outside of carina. Maxilla ( Fig. 11 ); cardo ( Fig. 12 ) constricted posteriorly; basistipes ( Fig. 13 ) subrectangular, longer than wide, with setae of various lengths, one setae of which distinctly thicker and longer; mediostipes with posterior margin strongly notched, with longitudinal carina, which distinct but not convex, on outside of carina with some short setae, on inside of carina with fine setae; galea long, brush-like; lacinia short, brush-like; apical three segments of palpus elongate; apical segment longest. Labium ( Fig. 14 ); mentum wide trapezoidal, translucent on apical 1/3, with short setae and two long setae on basal 2/3; prementum rounded anterad, with middle anterior notch rather deep, with a transverse row of setae posterior to the notch, fringed with fine setae (not represented in fig. 14); apical palpus segment longest.

Thorax. Pronotum wide trapezoidal, widened posterad, convex; sides linear in male ( Fig. 2 ), rounded broadly in female ( Fig. 3 ); posterior angles short, without carina, with rather rough surface; punctures umbilicate and coarse, becoming sparser posterad, smaller around basal margin. Prosternum ( Fig. 4 ) constricted posteriorly, punctures umbilicate and coarse; prosternal lobe slightly exceeding anterior angles of prothorax; prosternal process short, robust, expanded roundly at middle in ventral view, incurved lineally just behind procoxal cavity in lateral view ( Fig. 6 ), with apex rounded in ventral view and sharp in lateral view, with short subapical lobe. Pronotosternal sutures ( Fig. 4 ) closed frontally, not grooved, smooth band-like. Hypomeron ( Fig. 4 ) with umbilicate and coarse punctures, which distinctly larger than prosternal punctures. Mesosternum distinctly higher than metasternum at border of them. Mesepimeron reaching mesocoxal cavity. Scutellum elongate shield-shaped, widest at apical 1/3, strongly rounded anterad, with sharp apex; almost flat; inclined anterior downwards; punctures small. Metasternum ( Fig. 4 ) with shallow median longitudinal groove. Metacoxal plates ( Fig. 4 ) narrowed abruptly laterad. Elytra ( Figs. 2, 3 ) long, broadly convex; sides almost parallel on basal half, then roundly convergent towards apices; striae not grooved, but defined by distinct punctures; intervals with small punctures. Legs; tibial spurs well developed; tarsi and claws simple.

Abdomen. Sternite VII wide semicircular (length/width= ca. 0.75). Male. Tergite VIII ( Fig. 15 ) long semicircular (length/width= ca. 1.2), widest at basal 1/3; slightly translucent in median basal area; posterior margin fringed with setae of various lengths. Sternite VIII ( Fig. 16 ) wide sub-trapezoidal; posterior margin incurved shallowly at middle, with broadly rounded angles, which fringed with some setae of various lengths; anterior margin fringed with wide yellowish band limit of which indefinite. Tergite IX ( Fig. 17 ) slightly longer than wide; middle posterior notch deep and sharp; posterior angles with few setae. Tergite X ( Fig. 17 ) longer than wide; with a few short setae. Sternite IX ( Fig. 18 ) long, slightly widened posterad; posterior half covered with short setae and fringed with long setae. Female. Tergite VIII ( Fig. 22 ) long shield-shaped (length/width = ca. 1.5), widest at basal 2/5; apical margin strongly prominent, with dense and fine setae (not represented in fig. 22); apical 3/5 with dense numerous microtrichia (not represented in fig. 22) and fringed with setae of various lengths. Sternite VIII ( Fig. 23 ) coalesced tergite VIII at a part of lateral margin; basal area membranous, with definite limit between sclerotized area; sclerotized area longer than wide (length/width = ca. 1.2), with setae longer and denser apicad; speculum ( Fig. 24 ) elongate, attached to sclerotized area of sternite VIII ( Fig. 23 ).

Genitalia. Male. Aedeagu s ( Figs. 19, 20 ) elongate; median lobe longer than parameres; basal struts exceeding basal margin of parameres; parameres separate; apical portion of parameres long triangular, without setae in dorsal view and some long setae in ventral view ( Fig. 21 ). Female. Ovipositor ( Fig. 25 ) elongate; coxites ( Figs. 26, 27 ) with indefinite limit of two segments in ventral view; each coxite with two setae in dorsal view, with three setae in ventral view, with a short seta at apex; stylus with few setae near apex; vagina long, with two dome-shaped bulges; bursa copulatrix ( Fig. 25 ) thick and long, without sclerotized pieces; spermatheca ( Fig. 25 ) attached to apex of bursa copulatrix, coiled.

Larvae & Pupae. Unknown.

Diagnosis. This species is similar to A. lateritius Fleutiaux, 1940 , which is distributed from India to China, but distinguished by the combination of the following characteristics: the lighter orange body ( Figs. 2, 3 ), elytra suture not black or black-like, yellowish-brown setae, longer antennae ( Figs. 8, 9 ), and female tergite VIII and sternite VIII being longer ( Figs. 22, 23 ). This species is also similar to A. insolitus Platia, 2008 from Malaysia, but distinctly different with a wider body, larger and denser pronotal punctures, elongate scutellum, long triangular apical portion of parameres of male aedeagus ( Figs. 19–21 ), sclerotized area of female sternite VIII being short ( Figs. 23 ) and female bursa copulatrix being long and without sclerotized pieces ( Fig. 25 ).

Etymology. Dedicated to Mr. Hajime Yokoyama, the collector of specimens examined.

Bionomics. There is no information concerning the life history of this species. Some Agonischius species and other species of related genera are usually collected by sweeping the flowers of trees, because I suppose the long brush-like galea ( Fig. 11 ) of this species is useful for feeding on the pollen of flowers. Continuous observation is needed to determine their habits.

Figures

FIGURE 1. Collecting localities of Agonischius spp. in this study. A. Agonischius yokoyamai sp. nov. (black circles), A. lateritius (black triangles), A. insolitus (white triangle). B. Detailed collecting localities of A. yokoyamai sp. nov. (plots: a; Meifeng, type locality, b; Huitouwan to Tianxiang, c; Ruisui Township).

FIGURES 2 – 6. Agonischius yokoyamai sp. nov. 2, 4 – 6. Holotype, male. 3. Paratype, female. 2, 3: dorsal view; 4: ventral view; 5: head, antero-lateral view; 6: prosternal process, lateral view.

FIGURES 7 – 14. Agonischius yokoyamai sp. nov. 7, 8, 10 – 12. Holotype, male. 9. Paratype, female. 7: labrum; 8, 9: antennae; 10: mandible, dorsal view; 11: maxilla, posterior-lateral view; 12: cardo, posterior view; 13: stipes, ventral view; 14: labium. Scales: 1.0 mm for 8, 9; 0.2 mm for 7, 10 – 14.

FIGURES 15 – 27. Agonischius yokoyamai sp. nov. 15 – 21. Holotype, male. 22 – 27. Paratype, female. 15: tergite VIII; 16: sternite VIII; 17: tergites IX – X; 18: sternite IX; 19: aedeagus, dorsal view; 20: ditto, ventral view; 21: ditto, apical portion, ventral view; 22: tergite VIII; 23, 24: sternite VIII; 25: genitalia, dorsal view; 26: apex of ovipositor, dorsal view; 27: ditto, ventral view. Scales: 0.2 mm for 21, 26, 27; 0.5 mm for the others.