Delphacini Leach 1815

Tribe Delphacini Leach

Description. Gonapophyses IX slightly to moderately curvilinear (Figs 19, 20), average length 670.69–1487.50 µm, width 54.66–85.36 µm; number of teeth 22–31 (except Sardia rostrata [Fig. 20C] with 97 teeth); teeth varying from dentate to small and minutely rounded (except Stobaera tricarinata [Fig. 20D] with two sizes of round, knoblike teeth); teeth size uniform (except S. tricarinata); teeth extending three quarters of gonapophyses shaft (except S. tricarinata); most genera with ventral, membranous sheath, variable in extent; sensory structures or pits along entire, medial region; and apex porrect and serrate.

Notes. Delphacini represents the most speciose tribe with approximately 1,633 species in 315 genera, occurring worldwide (including oceanic islands, but excluding Antarctica). Plant associations are primarily graminoids, although genera such as Pissonotus and Stobaera occur on Asteraceae (Urban et al. 2010), and the Hawaiian fauna has shifted dramatically to various dicots (Zimmerman 1948, Wilson et al. 1994, Asche 1997, Roderick 1997, Roderick & Metz 1997). Wilson et al. (1994) reported that out of 238 non-island host associations for Delphacini, 92% were from monocots, 7% dicots and 1% Polypodiopsida; of the monocot records, 71% were from grasses and 13% sedges.