Genus Orius Wolff, 1811

Subgenus Dimorphella Reuter, 1884

O. (D.) tantillus (Motschulsky, 1863) — Distribution: Japan (Ryukyu Islands); known widely from the Old World subtropics and tropics, including Pacific islands.— Habitat and plant association: Graminoid grasses and inflorescence of various dicot angiosperms.

Subgenus Heterorius Wagner, 1952

O. (H.) hibiscus n. sp. — Japan (Ryukyus: Okinawa Island).—Currently known only from Hibiscus tiliaceus L. ( Malvaceae).

O. (H.) minutus (L., 1758)— Japan (Hokkaido, Honshu, Shikoku, Kyushu, and S. Chishima, Oki and Tsushima Islands); widespread over the Palaearctic Region and northern parts of Oriental Region (India, Thailand).— Found on various dicot herbs, including crops and inflorescence of broadleaf trees (cf. Yasunaga & Miyamoto, 1993; Yasunaga, 1997b; Yasunaga et al., 2001).

O. (H.) nagaii Yasunaga, 1993 — Japan (Hokkaido, Honshu, Shikoku, Kyushu, Tsushima Island), eastern China, Korea, Russian Primorsky Territory.—Preferably associated with graminoid grasses and often found from (chemical-free) rice paddy (Yasunaga, 1997b).

O. (H.) sauteri (Poppius, 1909) — Japan (most parts of temperate and cold temperate climate zones, including Chishima, Rebun, Rishiri and Tsushima Islands), China, Korea, Russian Far East (Amur, Khabarovsky and Primorsky Provinces, and Sakhaline).—Habitat and plant association as in O. minutus .

O. (H.) strigicollis (Poppius, 1915) — Japan (Honshu, Shikoku, Kyushu, and Koshiki, Ryukyu and Ogasawara Islands), eastern to southern China, Iran, Korea, Taiwan, Republic of Marshall Island (Majuro Atoll); however, populations of Japan and Marshall Island are considered to have been introduced (Yasunaga et al., 2018). The record from Iran (Ghahari et al., 2009) is doubtful (or presumably was based on introduced population).—Habitat and plant association as in O. minutus .

Subgenus Orius s. str.

O. (O.) takaii Yasunaga, 2000 — Japan (Ryukyus: Okinawa Island).—Available specimens collected only from Pueraria montana (Lour.) Merr. (Fabaceae); although all developmental stages were reported to be reared with spider mites ( Tetranychidae) (cf. Yasunaga, 2000a; Yasunaga et al., 2001), prey species in natural condition is yet to be observed.

Subgenus Trichorius Yasunaga, 1997

O. (T.) atratus Yasunaga, 1997 — Japan (Ryukyus), Taiwan.—Found predominantly from inflorescence or bracts of Macaranga tanarius (L.) Muell. Arg. and Mallotus spp. ( Euphorbiaceae) (Yasunaga et al., 2001); Ishida et al. (2009) presumed that O. atratus may use the enclosed chambers formed by floral bracts of Macaranga tanarius as breeding sites before and during flower anthesis, and feed on nectar on the adaxial surface of flower bracts.

Subgenus Xylorius Yasunaga, 1997

O. (X.) miyamotoi Yasunaga, 1997 — Japan (southwestern Honshu and Kyushu); currently considered endemic to Japan—Associated with deciduous oaks, Quercus acutissima Carruth. and Q. serrata Murray (Fagaceae) (Yasunaga, 1997a; Yasunaga et al., 2001).