Orius (Trichorius) crassus Yamada and Yasunaga

Yamada, Kazutaka, Yasunaga, Tomohide & Artchawakom, Taksin, 2015, The flower bug genus Orius Wolff, 1811 (Hemiptera: Heteroptera: Anthocoridae: Oriini) of Thailand, Journal of Natural History 50, pp. 1103-1157 : 1133-1135

publication ID	https://doi.org/ 10.1080/00222933.2015.1104393
DOI	https://doi.org/10.5281/zenodo.4332767
persistent identifier	https://treatment.plazi.org/id/EA370637-2046-0D00-4143-34D4FC04FB81
treatment provided by	Carolina
scientific name	Orius (Trichorius) crassus Yamada and Yasunaga
status	sp. nov.

Treatment

Orius (Trichorius) crassus Yamada and Yasunaga , sp. nov.

( Figures 3K,L View Figure 3 , 5L View Figure 5 , 10A View Figure 10 , 12D View Figure 12 , 17 View Figure 17 )

Type material

Holotype. ♂ ( Figures 3K, L View Figure 3 , 5L View Figure 5 , 10A View Figure 10 , 12D View Figure 12 , 17 View Figure 17 ), THAILAND, Nakhon Ratchasima, Sakaerat Environmental Research Station , N 14°30ʹ26.9ʺ, E101°55ʹ39.2ʺ, 407 m alt., light trap, 17 – 20 March 2010, T. Yasunaga & K. Yamada ( DOA).

Diagnosis

Recognised by the following characters: body generally greyish brown ( Figure 3K, L View Figure 3 ); hemelytra greyish brown, paler than pronotum and scutellum, cuneus somewhat darker than remainder of corium ( Figure 3K View Figure 3 ); antennal segment II thickened, fusiform ( Figure 5L View Figure 5 ); legs pale yellow, each femur dark brown excluding pale yellow apex ( Figure 3L View Figure 3 ); cone thin, pointed at apex in dorsal view, widened in lateral view, slightly elevated dorsally with weak projection ( Figure 17 View Figure 17 ); flagellum much longer than maximum width of cone, distinctly remote at base from the cone ( Figure 17 View Figure 17 ).

Description

Male (holotype). Colouration: body generally greyish brown ( Figure 3K, L View Figure 3 ). Head greyish brown, with paler apex; venter of head pale brown; eyes reddish brown, area surrounding ocellus red to reddish brown ( Figure 5L View Figure 5 ). Antennae yellowish brown; segment I dark brown; segments III and IV with dark brown tinge. Pronotum and scutellum greyish brown to blackish brown ( Figure 5L View Figure 5 ). Hemelytra greyish brown, paler than pronotum and scutellum; cuneus somewhat darker than remainder of corium; membrane uniformly somber dark brown ( Figure 3K View Figure 3 ). Legs pale yellow; each femur dark brown excluding pale yellow apex ( Figure 3L View Figure 3 ). Venter of thorax and abdomen dull greyish brown to dark brown ( Figure 3L View Figure 3 ). Structure: body oval ( Figure 3K View Figure 3 ). Head smooth, sparsely covered with short setae, 0.63 times as long as width across eyes, and with a longer erect seta on each side of clypeus, near anteromedial margin of each eye, and between eye and ocellus; ante-ocular portion 0.58 times as long as length of eye in dorsal view; vertex 1.9 times as wide as eye in dorsal view; eye proximate to anterior margin of pronotum, 1.3 times as long as eye width in dorsal view; neck indistinct ( Figure 10A View Figure 10 ). Antennal segment I stout, exceeding apex of head, sparsely covered with short suberect setae; segment II thickened, fusiform, 0.63 times as long as head width across eyes, densely covered with short suberect setae which are as long as width of the segment; segments III and IV slightly narrower than maximum width of segment II, covered with long erect setae intermixed with short decumbent setae, longest seta longer than width of respective segment; segment III slightly shorter than segment IV ( Figures 5L View Figure 5 , 10A View Figure 10 ). Labium extending to the procoxae, sparsely covered with short suberect setae. Pronotum smooth, shiny, sparsely covered with long decumbent setae; anterior margin nearly straight, width as wide as mesal length; lateral margin nearly straight, slightly angulate at anterior corner; lateral carinae expanded anteriorly; posterior margin shallowly concave, width 2.4 times as wide as anterior pronotal width; collar distinct, strigose, with transverse weak groove, demarcated by deep impression with short setae and tiny punctures from callus; callus strongly convex, impunctate, with scattered long setae, demarcated posteriorly by deep transverse impression with short setae and tiny punctures ( Figures 5L View Figure 5 , 10A View Figure 10 ). Scutellum nearly equilateral, slightly shorter than basal width, deeply depressed and covered with long setae through middle. Hemelytra overall sparsely covered with long decumbent setae and tiny punctures; costal margin rounded; maximum width of endocorium 1.87 times as wide as embolium; embolial margin rounded; cuneal margin slightly curved, about 0.57 times as long as embolial margin; membrane with two visible veins, one located near costal margin and one near posterior margin of the membrane. Legs densely covered with decumbent setae; male protibiae with a row of about 17 small fuscous teeth on ventral side. Male genitalia ( Figures 12D View Figure 12 , 17 View Figure 17 ): pygophore ovoid shaped, posteroventrally covered with 10 long, stout setae, of which the longest setae are about as long as half length of pygophore ( Figure 12D View Figure 12 ); mediodorsal surface densely distributed with short, suberect setae; cone thin and pointed at apex in dorsal view, widened in lateral view, slightly elevated dorsally with weak projection ( Figure 17 View Figure 17 ); flagellum with outer shorter branch and inner longer branch, shorter branch slightly bent at apex, longer branch nearly straight in dorsal view and much longer than maximum width of cone, basal portion of flagellum distinctly remote from the cone ( Figure 17 View Figure 17 ).

Female. Unknown.

Measurements (mm)

[♂ (n = 1)]. Body length 1.93; head length (excluding neck) 0.24; head width across eyes 0.38; vertex width 0.19; width between ocelli 0.13; lengths of antennal segments I – II: I – 0.09, II – 0.24, III – 0.17, IV – 0.19; lengths of labial segments II – IV: II – 0.06, III – 0.24, IV – 0.19; anterior pronotal width 0.33; mesal pronotal length 0.33; basal pronotal width 0.78; length of embolial margin 0.63; length of cuneal margin 0.36; maximum width across hemelytra 0.89.

Etymology

From Latin, crassus (= thick, stout), referring to thickened, fusiform male antennae; an adjective.

Distribution

Northeastern Thailand (Nakhon Ratchasima).

Remarks

Orius crassus evidently differs from O. atratus Yasunaga, 1997 from Japan and Taiwan in having a generally greyish brown body (in atratus , shiny blackish), the hemelytra being paler than pronotum and scutellum with somewhat darker cuneus (in atratus , shiny dark, chestnut brown to more blackish), the much thicker male antennae (in atratus , not strongly thickened in male), and the labium being extending to the procoxae (in atratus , reaching the mesocoxae). In the male genitalia, however, there are few differences between crassus and atratus . The former can be distinguished from the latter by the flagellum with nearly straight inner longer branch (in atratus , sinuate) and the basal portion of flagellum being distinctly remote at base from the cone (in atratus , rather proximate to base of cone).

Habitat

Unknown. A single specimen was collected with an ultraviolet light trap.