Protosclerogibba Olmi, Marletta, Guglielmino & Speranza, 2016

Olmi, Massimo, Marletta, Alessandro, Guglielmino, Adalgisa & Speranza, Stefano, 2016, Protosclerogibba australis gen. et sp. nov., new genus and species of sclerogibbid wasps (Hymenoptera: Sclerogibbidae) from South Africa, Zootaxa 4085 (1), pp. 127-134 : 128-129

Protosclerogibba Olmi, Marletta, Guglielmino & Speranza , gen. nov.

( Figs 1–5 )

Type species: Protosclerogibba australis sp. nov.

Diagnosis. See description below.

Description. Female. Micropterous ( Figs 1, 2 , 4, 5 ); fore wing very reduced, about twice as long as scutellum, without veins ( Figs 1, 2 , 4, 5 ); hind wing reduced, about half as long as fore wing; head with three ocelli ( Fig. 1 ); frons not produced over base of antennae (antennal toruli not concealed in dorsal view) ( Figs 2 , 4, 5 ); eyes large, situated in the posterior three fourths of the head ( Figs 1, 2 , 4, 5 ); head with posterior margin much longer than anterior one ( Figs 1 , 4 ); first antennal segment slightly longer than anterior flat surface of the hypostomal bridge ( Fig. 3 ); palpal formula 6/4; antenna 12-segmented ( Figs 1, 2 ); scutum, scutellum, metanotum and propodeum separated by distinct sutures ( Figs 1 , 4 ); mesosoma not crossed by a straight suture separating the metanotum and scutellum from the propodeum ( Figs 1 , 4 ); metanotum composed of two narrow pieces situated on sides of scutellum and hidden under wings; profemur strongly enlarged ( Figs 1, 2 , 4, 5 ), meso- and metafemur less enlarged ( Figs 1, 2 , 4, 5 ); tibial spurs formula 1/2/2. Male. Unknown.

Differential diagnosis. The main distinctive characters of Protosclerogibba are the following: female micropterous ( Figs 1, 2 , 4, 5 ); frons not produced over base of antennae (antennal toruli not concealed in dorsal view) ( Figs 2 , 4, 5 ); eyes large, occupying the hind three fourths of the head ( Figs 1, 2 , 4, 5 ); palpal formula 6/4; antenna composed of 12 segments ( Figs 1, 2 ). The three above characters cannot be found in other genera of sclerogibbids. In fact females of other extant sclerogibbids are always apterous ( Figs 6–8 ), with frons produced over base of antennae (antennal toruli concealed in dorsal view) ( Fig. 9 ), eyes small, occupying the hind two thirds of the head ( Figs 6–8 ); palpal formula varying from 2/1 to 6/3, never 6/4; antenna composed of 14–39 segments ( Figs 6–8 ). In the few known fossil sclerogibbids (three known specimens, all females), the females are macropterous (in Sclerogibbodes embioleia and Pterosclerogibba antiqua ) ( Fig. 14 ) or apterous (in Probethylus poinari Olmi, 2005 ) ( Fig. 13 ); no males of fossil sclerogibbids are known.

Hosts. Unknown.

Etimology. The name of the new genus is formed by proto- and Sclerogibba , meaning first Sclerogibba in order of time among the extant species.

Species. Type species only.

Distribution. South Africa.

Figures

FIGURES 1 – 3. Protosclerogibba australis sp. nov., holotype, ♀. 1, dorsal view; 2, lateral view; 3, head in ventral view (a: first antennal segment; h: hypostomal bridge). Seventh exposed segment of gaster very small. Scale bar 1.89 mm (1), 1.87 mm (2), 0.93 mm (3).

FIGURES 4 – 5. Protosclerogibba australis sp. nov., holotype, ♀. 4, dorsal view; 5, lateral view (metasoma in unnatural horizontal position for better gluing it to the label; natural position is oblique and vertical as in figure 2). Scale bar 1.94 mm (4), 1.80 mm (5).

FIGURES 6 – 8. Females of Sclerogibbidae. 6, Caenosclerogibba longiceps (Richards); 7, Probethylus callani Richards; 8, Sclerogibba magrettii (Kieffer). Scale bar 0.69 mm (6), 1.36 mm (7), 1.52 mm (8).

FIGURES 9 – 12. 9. Probethylus callani Richards, ♀, lateral view. 10 – 12, head in ventral view of females of Probethylus callani Richards (10), Probethylus schwarzi Ashmead (11) and Sclerogibba embiopterae Dodd (12). a: first antennal segment; h: hypostomal bridge. Scale bar 1.05 mm (9), 0.13 mm (10), 0.92 mm (11), 0.20 mm (12).

FIGURES 13, 14. Fossil females in amber of Probethylus poinari Olmi (13) and Pterosclerogibba antiqua Olmi (14). Scale bar 0.49 mm (13), 0.57 mm (14).