Lacusa Stal

Xing, Jichun & Chen, Xiangsheng, 2014, Taxonomic study of the planthopper genus Lacusa Stal, 1862 (Hemiptera, Fulgoromorpha, Lophopidae), ZooKeys 405, pp. 139-148 : 140-142

Lacusa Stal

Lacusa Stål, 1862: 309; Atkinson 1886: 42; Distant 1906: 323; Muir 1930: 478; Chou et al. 1985: 125; Liang 2000: 283.

Type species.

Elasmoscelis fuscofasciata Stål, 1854

Description.

Body length (from apex of vertex to tip of forewings) less than 10 mm, size medium. Head short, approximately trapezoidal, ratio width of vertex from base to length in middle line 1.6, narrower than pronotum; vertex broader than long, anterior margin straight in dorsal view and not produced anteriorly beyond proximal margin of eyes, lateral margins with carinate, with an obsolete median longitudinal carina. Frons with lateral carinae, and with sublateral carinae fused apically, and without median carina. Rostrum extending to meso-trochanter, with ratio subapical to apical segment 2.0. Pronotum slightly longer than vertex, anterior margin roundly produced, posterior margin approximately straight, tricarinate on disc, lateral areas curved down. Mesonotum broad, with tricarinate on disc. Forewings broadly round at apex, outer and inner margins nearly parallel, precostal area with many oblique transverse parallel crossveins; hindwings narrower than forewings. Legs moderately long, fore femora and tibiae foliaceous. Hind tibiae with 3 lateral spines and 3-4 rows with more than 70 small spines apically, apical spines of first hind tarsal segment separated by a pad of microsetae.

Head pale luteous, suffused with piceous brown. Eyes black brown. Frons brown and anteclypeus piceous brown. Antennae black brown. Rostrum yellowish brown. Forewings semiopaque, with three broad fuscous transverse band and irregularly piceous spots; hindwings semihyaline. Fore and middle legs blackish brown; hind legs luteous, pad yellowish. Abdomen piceous brown.

Male genitalia. Pygofer short, upper 1/3 very narrow in lateral view, without appendage. Anal tube longer than pygofer, apex forked in caudal view. Genital styles short to long, dorsolateral with a small hook or a finger-like process near posterior margin. Aedeagus with 2 dorsally directed, spinose processes, dorsally directed at medioventral margin; near base of aedeagus on dorsal side or mediolateral of aedeagus with 2 spinose processes or not; base of aedeagus on dorsal side with 1 spinose process or not, and each base laterally of aedeagus with 1 processes or not.

Diagnosis.

The genus Lacusa resembles Pitambara Distant, 1906 and Sarebasa Distant, 1909 in having the vertex not produced anteriorly beyond proximal margin of eyes, apical spines of first hind tarsal segment separated by a pad of microsetae, and frontal disc not longitudinally deeply concave, but differs from these genera by the characters noted in Table 1.

Distribution.

China, India, Nepal, Burma, Thailand.

Key to species (male) of Lacusa from China