Bilia Distant 1904
Creators: name: Yasunaga, Tomohide
name: Yamada, Kazutaka
name: Soe, Zayar
name: Naing, Shine Shane
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Anthocoridae
Bilia

description: Genus Bilia Distant, 1904
Bilia Distant, 1904: 480 (in Miridae) (type species by original designation: B. fracta Distant, 1904); Carayon (1958: 154, 159) (transferred to tribe Oriini of Anthocoridae); Carayon & Miyamoto (1960: 20−26) (redesc.); Péricart (1996: 121) (cat.); Yasunaga (2000: 353) (diag.); Yasunaga (2001: 284) (diag.); Bu & Zheng (2001: 177) (diag.).
Biliola Carvalho, 1951: 386 (in Miridae), type species by monotypy: Biliola castanea Carvalho, 1951 (synonymized by Carayon & Miyamoto 1960: 25); Carayon (1958: 160) (transferred to tribe Oriini of Anthocoridae).
Diagnosis. Distinguished from other anthocorid genera by the following combination of characters: rounded, tortoise-shaped body; basic coloration brown to fuscous; shiny dorsal surface with uniformly distributed, wooly, reclining or semi-erect setae; short and widened head; male paramere C- or J-shaped, slender, apically tapered and accompanied by a median, small, slender projection (Figs. 24−25, 27) that is homologous with ‘flagellum’ in Orius (Fig. 31) and Wollastoniella (Figs. 33−34); female copulatory tube fragile, totally membranous (Fig. 26). The immature form has a fuscous, rounded, hemispheric body (Fig. 6). Detailed generic characters were provided by Carayon & Miyamoto (1960).
Distribution. Known from the Oriental and eastern Palearctic regions; currently recorded from China, India, Japan, Myanmar, Taiwan, and Russian Far East.
Discussion. This genus is closely related to Wollastoniella, from which it may be separated only by the genitalia; the diagnostic features were argued extensively by Carayon (1958) and Carayon & Miyamoto (1960). Bu & Zheng (2001) and Carayon (1958) suggested the general body shape and puncture pattern on the pronotum as key diagnostic characters; however, these external characters are now found not to be applicable to every species. In addition, the immature forms of Bilia and Wollastoniella species exhibit totally similar (or fundamentally identical) shape (cf. Figs. 6 and 17).
Bilia is posited to be composed of Asian elements, based on the distribution patterns of the nine known species from India and Sri Lanka to Java, the Sundaland (Carayon 1982) and the Pacific Islands (Yasunaga 2000); more than a few undescribed species have also been found in Peninsular Malaysia, Nepal and Thailand (Yamada & Yasunaga, unpublished data). In the Oriental Region including the Himalayan area, both Bilia and Wollastoniella are known (Bu & Zheng 2001). Although the latter genus occurs in Africa (Carayon 1958; Ghauri 1987), the two genera are most probably derived from a lineage (cf. Figs. 32–34, B) once present in the Himalayan region where many Asian organisms are assumed to have originated. To demonstrate this hypothesis, however, further broader surveys on the characters are required, which is beyond the scope of this work.
Members of the genus appear to be predaceous as evidenced by B. esakii and B. japonica that have been observed preying on typhlocybine leafhoppers and/or psyllids (Yasunaga 2001). Carayon & Miyamoto (1960) also documented that B. japonica preyed on the eggs and nymphs of cicadellid leafhoppers, and B. castanea was reported as a natural enemy of Lipaphis erysimi (Kaltenbach, 1843) (Aphididae) which is injurious to black mustard, Brassica nigra L. (Brassicaceae) (Ghosh et al. 1981). These observations suggest that Bilia species may prefer hemipterous insects rather than thrips which are generally preferred by Wollastoniella species.
description: Published as part of Yasunaga, Tomohide, Yamada, Kazutaka, Soe, Zayar & Naing, Shine Shane, 2016, First records of two flower bug genera from Myanmar (Hemiptera: Heteroptera: Anthocoridae: Anthocorinae: Oriini), with description of a new species of Bilia, pp. 544-556 in Zootaxa 4158 (4) on page 546, DOI: 10.11646/zootaxa.4158.4.6, http://zenodo.org/record/258305