Trigonocera Becker, 1902

Grootaert, Patrick, Velde, & Isabella Van de, 2024, New long-legged flies from mangroves on Pulau Ubin (Singapore) (Insecta: Diptera: Dolichopodidae), Raffles Bulletin of Zoology 72, pp. 303-323 : 309-310

Genus Trigonocera Becker, 1902

Trigonocera Becker, 1902: 57 . Type species: Trigonocera rivosa Becker, 1902 , by monotypy. Grichanov, 2011: 6; Yang et al., 2011: 1237, 1718.

A diaphorine genus with a subtriangular postpedicel in males and frons and face broadly separated. Postpedicel in females shorter than in males. The pedicel seems to make a projection into the base of the postpedicel, which separates this genus from Diaphorus ( Grichanov, 2011) .

According to Liu et al. (2018), there are only nine extant species in the world, all confined to the Old World, with four species in the Afrotropical realm, one in the Palaearctic realm, and seven in the Oriental realm. A key for all the world species is also provided by Liu et al. (2018). The following species are actually known from the Oriental region: T. biseta Olejníček, 2004 , T. guizhouensis Wang, Yang & Grootaert, 2008 , T. lucidiventris Becker, 1922 , T. specialis Becker, 1922 , T. shuensis Liu & Yang, 2018 (in Liu et al., 2018), T. tongshiensis ( Yang, 2002) . The presence of T. rivosa Becker, 1902 , a so-called tramp species all over the Old-World tropics, is to be confirmed since the male terminalia of the Oriental specimens were, to our knowledge, never examined.

The genus Trigonocera is reported here for the first time in Singapore.