Gergithus Stål, 1870

Figs 1–7

Gergithus Stål, 1870: 756 .

Type species: Hemispharius schaumi Stål, 1855, by original designation.

Diagnosis

Coryphe subquadrate (Figs 2A, 5A, D, 6A), metope elongate (Figs 2C, 5B, F, 6D, 7C), postclypeus nearly triangular and in same oblique plane with metope, anteclypeus angular (Figs 2D, 5C, E, 6B, 7B) and tegmen with costal margin moderately convex at basal one third as “relief shoulder” (Figs 2A, 5A, 6A, 7A).

Redescription

Coryphe subquadrate, margins carinate, anterior margin straight or weakly concave, posterior margin weakly concave (Figs 2A, 5A, D, 6C, 7A). Metope greatly elongate, slightly widening below antennae; upper margin straight (Figs 2C, 5B, F, 6D, 7C). Metopoclypeal suture straight (Figs 2C, 5B, F, 6D, 7C). Postclypeus nearly triangular and in same oblique plane, with lateral margins continuous with those of metope; anteclypeus extremely narrow in ventral view, and roundly angulately protruding ventrally in lateral view (Figs 2 C–D, 5B–C, E–F, 6B, D, 7B–C). Ocelli rudimentary. Pronotum clearly short, as long as coryphe in middle line or slightly shorter than it, extremely narrow behind eyes, margins obviously ridged; lateral lobes large, fan-shaped in frontal view, ventral margins moderately oblique, lateroventral angles obtusely convex (Figs 2A, C, 5 A–B, D, F, 6C–D, 7A, C). Mesonotum with anterior margin obviously ridged and shallowly concave, with two rounded pits medially on each side (Figs 2A, 5A, D, 6C, 7A). Tegula small. Tegmen ovate-oblong, depressed at basal surface, costal margin moderately convex at basal one third as “relief shoulder”, longitudinal veins prominent, with many supernumerary branches and numerous irregular transverse veinlets; claval suture absent (Figs 2F, 5 C–D, 6E, 7B). Hind wing mostly well-developed single lobe, veins netlike, sometimes reduced (Fig. 2G). Legs moderately long, not dilated; hind tibia with two spines distally.

Distribution

Sri Lanka, India, Burma, Thailand, China (Yunnan Province), Malaysia, Indonesia.

Remarks

From a total of 62 species previously included in the genus we transfer several species to a new genus described below and transfer G. contusus (Walker, 1851) to Mongaliana. However, a detailed revision of the latter genus is needed in the future. Twenty two species are retained in Gergithus, most of them after examination of the type (Butler 1875; Distant, 1906, 1916; Walker 1851) or of other specimens in the BMNH. Images of type specimens are provided for: G. schaumi (Stål, 1855) (Fig. 7 A–D), G. cribratus Melichar, 1906 (Fig. 5 D–F) and G. signatifrons Melichar, 1906 (Fig. 6 A–F). The species G. ignotus Melichar, 1906, G. lineolatus Melichar, 1906, G. pigrans Melichar, 1906, G. secundus (Melichar, 1903) and G. vidulus Melichar, 1906 are known by their original descriptions only.

Checklist of species of Gergithus Stål, 1870

Species in BMNH indicated by *:

* G. bipustulatus (Walker, 1858) . As Hemisphaerius bipustulatus Walker, 1858: 95, Sri Lanka

* G. complicatus Distant, 1916 . Distant 1916: 103, fig. 77, Sri Lanka

* G. conspicularis Distant, 1916 . Distant 1913: 103, Sri Lanka

* G. cribratus Melichar, 1906 . Melichar 1906: 64, Sri Lanka (Fig. 5 D–F)

* G. dubius (Butler, 1875) . As Hemisphaerius dubius Butler, 1875: 97, pl. IV, fig. 17, Sri Lanka

* G. elongates (Distant, 1906) . As Hemisphaerius elongatus Distant, 1906: 362, India

* G. erebus Distant, 1916 . Distant 1916: 101, fig. 76, India

G. frontilongus sp. nov., China (Yunnan) (Figs 2–4)

* G. herbaceous (Kirby, 1891) . As Hemisphaerius herbaceous Kirby, 1891: 147, Sri Lanka

G. ignotus Melichar, 1906 . Melichar 1906: 66, Burma

G. lineolatus Melichar, 1906 . Melichar 1906: 60, Sumatra

* G. niger (Walker, 1857) . As Hemisphaerius niger Walker, 1857: 155, Indonesia, Malaysia, Thailand As Hemisphaerius walkeri Butler, 1875: 100, replacement name for Hemisphaerius chilocoroides Walker, 1862: 308 . Synomized by Liang (2001)

* G. nilgiriensis (Distant, 1906) As Hemisphaerius nilgiriensis Distant, 1906: 361, India

G. pigrans Melichar, 1906 . Distant 1906: 64, Indonesia (Kei Island)

* G. proteus Distant, 1916 . Distant 1916: 102, India

* G. reticulatus (Distant, 1906) . As Hemisphaerius reticulatus Distant, 1906: 361, India

* G. schaumi (Stål, 1855) . As Hemisphaerius schaumi Stål,1855: 191, Sri Lanka (Fig. 7 A–D)

G. secundus (Melichar, 1903) . As Hemisphaerius secundus Melichar, 1903: 75, Sri Lanka

G. signatifrons Melichar, 1906 . Melichar 1906: 60, Indonesia (Sumatra) (Fig. 6 A–F)

* G. venosus (Distant, 1906) . As Hemisphaerius venosus Distant, 1906: 363, India

* G. versicolor Distant, 1916 . Distant 1916: 102, Sri Lanka

G. vidulus Melichar, 1906 . Melichar 1906: 62, India