Theronus priapus, Stiller, M., 2009

Stiller, M., 2009, Revision of Elginus Theron (Hemiptera: Cicadellidae: Deltocephalinae) with the description of two new genera and comments on the grassland leafhopper fauna in South Africa, Zootaxa 2135 (1), pp. 1-56 : 34-35

Theronus priapus sp.n.

( Figs 47–49 , 284–290 )

Diagnosis. Undissected specimen with uniform, stramineous colouration, except for paired dark brown marks on pygofer. Antenna long, about one-third as long as specimen. Male genitalia in ventral view with plates contiguous, with apices forming a U-shaped notch. Plate with posterior margin with lateral, dorsally directed tooth and dorsal tooth at base of notch. Apex of aedeagal shaft sometimes protruding ventrally between pygofer lobes. Aedeagus with long, blade-shaped shaft; length about as long as pygofer. Connective and base of styles well retracted into tergite VII; fused with aedeagus.

Etymology. Greek, god of reproduction, for the outsized genital structure.

Colour. Male & Female. Brachypter stramineous, no fuscous marking except variably feint, paired markings dorsally on proximal margin of pygofer; tegmina translucent, costal cell stramineous ( Figs 47–49 ). Macropter darker stramineous to ochraceous, with tegmina and hind wing opaque; face embrowned; lateroanterior margin of pygofer with irregular, paired fuscous marking.

Abdominal apodeme. Figs 274, 275 .

Dimensions. Male (n = 40). Lengths: flagellum (vector) 1.0– 1.2 mm; apex of vertex to apex of tegmina 2.2–2.3 mm, apex of vertex to apex of abdomen 2.2–2.3 mm; vertex medially 0.4 mm; vertex laterally next to eye 0.3 mm; pronotum medially 0.3 mm; scutellum medially 0.2–0.3 mm. Maximum widths: head 0.8–0.9 mm; pronotum 0.7 mm; scutellum 0.4 mm. Ocellus: diameter 13–16 µm; ocellocular distance 39–49 µm.

Genital capsule. Male. Aedeagus long, extending into tergite VII, blade-like, tapering, curved ventrally, sometimes protruding posteroventrally ( Figs 284, 285 ). Plate and valve fused basally; apex with recess; medial margins contiguous, forming U-shaped notch; tooth dorsally at base of notch; tooth at apex ( Fig. 286 ). Pygofer lobe anterior margin with distinct apodeme, posteroventrally with membranous extension, macrosetae present ( Fig. 290 ). Anal tube recessed into pygofer by about one fifth length of pygofer ( Fig. 287 ). Style apophysis wide, serrate inner margin; preapical lobe ventral ( Fig. 288 ).

Dimensions. Female (n = 30). Lengths: flagellum (vector) 1.0– 1.2 mm; apex of vertex to apex of tegmina 2.5 mm, apex of vertex to apex of abdomen 2.2–2.3 mm; vertex medially 0.5 mm; vertex laterally next to eye 0.3–0.4 mm; pronotum medially 0.3 mm; scutellum medially 0.3 mm. Maximum widths: head 1.0 mm; pronotum 0.8 mm; scutellum 0.4 mm. Ocellus: diameter 14 µm; ocellocular distance 56 µm.

Genital capsule. Female. Third valvula with two apical macrosetae (24.5 and 25.1 µm in length), distal setae much shorter (9–10 µm). First valvula lanceolate; sculpture imbricate. Second valvula finely serrate. Sternite VII medial section M-shaped; dorsally with sternite VIII scleoritzed, supported by single pair of pillars between sternite VII and VIII ( Fig. 289 ).

Material examined. Holotype male. South Africa, Western Cape. Theewaterskloof Dam, 33°59ʹS 19°11ʹE, 16.xii.2004, M. Stiller, DVac Cannomias sp. ( Restionaceae ) and sedges in mountain fynbos wetland ( SANC). Paratypes (45♂, 42♀). Western Cape. 4♂, 1♀, Stellenbosch Jonkershoek, (33°56ʹS 18°51ʹE), 23.xi.–28.xii.1971; 11♂, 4♀, ibid. above, but 2.ii.1972; 17♂, 12♀, ibid. above, but 14.vii.1977; all J.G. Theron; 8♀, Hottentotsholland Nature Reserve, N Grabouw, 34°03'S 19°01'E, 15-18.x.2002, 450– 1070m, M. Stiller; 12♂, 12♀, ibid. holotype; 5♀, Betty’s Bay, 34°22ʹS 18°56ʹE, 19.xii.2004, M. Stiller, DVac grass in fire break, common plant species: Micranthus sp. (Iridaceae) , Erhartha sp., Pentaschistis ? curvifolia ( Poaceae ) ( AMNH, BMNH, SANC).

Remarks. Macroptery is rare, with 1 male (45 specimens examined) and 5 females (42 specimens examined) being macropterous, with hind wing as long as forewing, and the wings extending well beyond the posterior margin of abdomen.

Some undescribed species of Pravistylus have a similar colour pattern. The brachyptery in these species of Pravistylus is more pronounced than in T. priapus . However, internal and external male genitalia differ significantly. Vilargus pumilicans ( Theron, 1975) has its forewing distinctly shorter than the abdomen with a distinctly different genital configuration. In T. priapus the abdomen and forewing have the same length, with the hind wing reduced. Distributions also differ, with T. priapus probably restricted to the Fynbos Biome and V. pumilicans known from the Grassland Biome, and with the undescribed Pravistylus species probably having the widest distribution, being common in the Grassland Biome, but extending into the Savanna and Fynbos Biomes.

Theron regularly collected in the Jonkershoek valley near Stellenbosch, where the species was probably abundant on grass regrowth after fire. This was also the case at Betty’s Bay, where specimens were found in a fire break. It is not known how this species colonizes new habitats, but presumably the offspring of short winged individuals develop normal hind wings when its food source declines. Perhaps this species could be described as a flitter as defined by Waloff and Solomon (1973) and Waloff (1980). The straight line distance between these three localities where it was found is not large, but separated by mountain ranges. It could however be possible that the species randomly and sporadically is able to utilize even small patches of grass. The species is probably absent from the Cape Peninsula, and was not found in the Schlettwein and Giliomee (1987) survey of Jonkershoek. It was only present at two localities during a survey of the Western Cape in December 2004, in the course of which 46 localities and up to 157 habitats or grass species were examined.

Figures

FIGURES 47–50. Theronus priapus and Lecacis species, habitus views. Fig. 47, T. priapus sp.n., male; Fig. 48, T. priapus, female brachypter; Fig. 49, T. priapus, female macropter; Fig. 50, L. platypennis Theron, male.

FIGURES 284–290. Theronus priapus. Fig. 284, aedeagus, ventral view; Fig. 285, aedeagus, lateral view; Fig. 286, plate and valve; Fig. 287, apex of abdomen, dorsal view, depicting position of genitalia; Fig. 288, style; Fig. 289, sternite VII, female; Fig. 290, apex of abdomen, lateral view, depicting position of genitalia.

FIGURES 274–283. Micropedeticus ochrus. Fig. 274, abdominal apodeme, posterior; Fig. 275, abdominal apodeme, anterior; Fig. 276, aedeagus, dorsal view; Fig. 277, aedeagus, lateral view; Fig. 278, connective; Fig. 279, plate and valve; Fig. 280, pygofer, dorsal view; Fig. 281, pygofer, lateral view; Fig. 282, style; Fig. 283, sternite VII, female.