Belbina Stål, 1863

Belbina Stål, 1863a: 232 . Type species: Belbina falleni Stål, 1863 by subsequent designation by Lallemand (1959).

Cornelia Stål, 1866: 133 (key), 142. syn. nov. Type species: Cornelia nympha Stål, 1866, by monotypy.

Belbina – Stål 1863b: 580 (redescription). — Stål 1866: 134 (key), 143 (description, key to species). — Karsch 1890: 61 (listed; erroneous synonymy with Pyrgoteles Gertsaecker, 1873). — Jacobi 1917: 520 (listed). — Lallemand 1922: 62 (listed, description of new species). — Metcalf 1947: 123 (catalogued). — Lallemand 1950: 84 (description of new species). — Lallemand 1959: 85 (key), 88 (description, key to species). — Nast 1977: 30 (nomenclature). — Constant 2004b: 31 (key, list of species).

Cornelia – Karsch 1890: 61 (listed). — Schmidt 1911: 241 (listed, description of new species). — Jacobi 1917: 520 (listed). — Metcalf 1947: 122 (catalogued). — Lallemand 1959: 85 (key), 86 (description, key to species). — Constant 2004b: 31 (key, list of species).

Druentia – Schumacher 1918: 111 pars (erroneous synonymy).

Remarks

Belbina and Cornelia are synonymized because it is not possible to find any characters allowing consistent separation of these taxa. When all species of both genera are taken into account, a gradient can be observed from the larger species (e.g., falleni and recurva) to the smaller ones (e.g., nympha and bergrothi) in all characters supposed to separate the genera, i.e., (1) the width of the vertex (supposedly narrower than eye in Cornelia and broader than eye in Belbina), (2) vertex prolonged directly on cephalic process ( Cornelia) or not ( Belbina) and (3) hind margin of tegmina cut transversely ( Cornelia) or rounded ( Belbina).

The close relationship and possible synonymy of Belbina and Druentia mentioned by Constant (2004) is not supported by the results of recent molecular studies. According to a preliminary analysis (Julie Urban pers. comm., Nov. 2013), Druentia is sister to Rhicnophloea Gerstaecker, 1895 and [ Druentia + Rhicnophloea] is sister to a larger clade of Old World taxa which contains, among others, a group formed by [ Samsama Distant, 1906 + Belbina + Metaphaena Schmidt, 1905 + Anecphora + Penthicodes] (Urban, Bartlett & Cryan unpubl. data).

Five of the twelve currently known species of Belbina seem very close and share very similar male genitalia with the following common characters: (1) pygofer, anal tube and gonostyli red or dark red; (2) gonostyli elongate with ventral margin concave in lateral view and roundly pointed apically; (3) gonostyli with strong basodorsal digitiform process directed dorsolaterally or dorsoposteriorly; (4) anal tube broadening more or less regularly from base to apex. This group is defined as the falleni + group and contains B. bloetei, B. falleni, B. laetitiae sp. nov., B. lambertoni and B. pionneaui .

Diagnostic characters

The genus can be recognized by the following combination of characters: (1) head much narrower than pronotum; (2) frons longer than broad, with longitudinal carinae; (3) cephalic process present, about as long as frons and projecting anterodorsally to posterodorsally; (4) lateral carinae of cephalic process (i.e., prolongation of the lateral carinae of frons and of vertex) fused in a single longitudinal carina before apex of process; (5) pronotum with a strong tectiform median carina and a deeply impressed point on each side of it.

Belbina is very similar to Druentia but can be separated by character (4): in Druentia the lateral carinae of the vertex reach the apex of the cephalic process without fusing together.

Sexual dimorphism

Males 15 to 30% smaller in size than females.

Distribution

Only recorded from Madagascar.

Identification key to the species of Belbina

The disc of the hind wings can be either orange or red in some species (observed in B. bergrothi, B. madagascariensis and B. nympha). It is possible that other species presently known only from red hind-winged specimens also have ones with orange hind wings.

The red colour of the abdomen can also fade to orange or yellow in collection specimens, especially if they have been preserved in ethanol.

1. Hind wings red or orange on disc (Figs 1A, 2A)........................................................................2

– Hind wings with disc bluish, greenish or brown (Figs 3A, 6A)...................................................10

2. Ground colour of tegmina orange or red (Figs 1A, 7A, 10A)...................................................3

– Ground colour of tegmina brown to pale rosy brown (Figs 2A, 4A)........................................5

3. Mesonotum with 2 black patches on disc (Fig. 1C); small-sized (less than 22 mm long) ........... .................................................................................................... Belbina bergrothi (Schmidt, 1911)

– Mesonotum without black patches (Figs 7C, 10C); larger (more than 24 mm long)...............4

4. Tegmina orange to red with minute black spots; 3 large black patches on costal cell and one at the base of clavus (Fig. 7A) ................................................... Belbina lambertoni Lallemand, 1922

– Tegmina dark red with membrane pale brown; numerous, irregular, blackish brown spots (Fig. 10A) .......................................................................................... Belbina pionneaui Lallemand, 1922

5. Head with a foliaceous process above the eye, higher than diameter of eye in side view; median carina of pronotum strongly sinuate and elevated posteriorly in side view (Fig. 5D) ..... ..................................................................................................... Belbina foliacea Lallemand, 1959

– Head without large foliaceous process above the eye, process reduced to a lamina not higher than half of diameter of eye; median carina of pronotum not strongly sinuate and elevated posteriorly in side view (Figs 4D, 11D).....................................................................6

6. Small-sized, less than 22 mm long; cephalic process directed anterodorsad (Fig. 9D); abdomen with 2 dorsal rows of black spots; hind wings with 4–6 little black spots on red zone (Fig. 9A) ............................................................................. Belbina nympha (Stål, 1866)

– Larger, more than 26 mm long; cephalic process angulously directed dorsad or posteriorad (Fig. 2D), or, if not, dorsum of abdomen red without rows of black spots; hind wings with 2 small black spots or larger black spots (Figs 4A, 8A)...................................................7

7. Cephalic process narrow, elongate, obliquely directed anterodorsad (Fig. 8D); blackish brown spots with pale center on tegmina (Fig. 8A) ............ Belbina madagascariensis (Westwood, 1851)

– Cephalic process broad, strongly curved dorsad or posteriorad (Fig. 2D); dark spots on tegmina without pale center (Figs 2A, 4A)...................................................................................................8

8. Cephalic process projecting dorsad, apex not surpassing level of anterior margin of eye in lateral view (Fig. 2D); abdomen without rows of black spots dorsally; no large black patch on basal half of claval joint; no paler transverse patch at half length of tegmen (Figs 2A, 4A)...9

– Cephalic process more strongly curved and projecting posterodorsad, reaching level of posterior margin of eye in lateral view (Fig. 11D); abdomen with 2 rows of blackish spots dorsally; one large black elongate patch on basal half of claval joint; one transverse paler patch at about half of length of tegmen (Fig. 11A) ....................... Belbina recurva Lallemand, 1950

9. Ground colour of tegmina and head pale rosy brown; a rectangular paler patch on clavus (Fig. 2A) ................................................................................................ Belbina bloetei Lallemand, 1959

– Ground colour of tegmina and head brown; no evident paler patch on clavus (Fig. 4A) ............. ................................................................................................................. Belbina falleni Stål, 1863

10. Head, pro- and mesonotum red (Fig. 12C–E); ground colour of tegmina bluish green (Fig. 12A) ........................................................................................................ Belbina servillei (Spinola, 1839)

– Head, pro- and mesonotum brown (Figs 3C–D; 6C–D); ground colour of tegmina bluish green or brownish (Figs 3A, 6A)............................................................................................................11

11. Ground colour of tegmina bluish green; hind wings nearly totally infuscate with a suturobasal, not well limited zone, and spots, paler, milky (Fig. 6A); larger (24 mm long in males, 27 mm long in females) ...................................................................... Belbina laetitiae sp. nov.

– Ground colour of tegmina brownish with a dark reddish band after half of length; hind wings with paler, bluish green disc very distinctly separated from blackish apex and sutural margin (Fig. 3A); smaller (19 mm long in males) ............................................. Belbina bourgoini sp. nov.