Schizohelea Kieffer, 1917

Szadziewski, Ryszard, Dominiak, Patrycja, Rumišek, Mario, Neinhuis, Christoph, Wanke, Stefan & Rupp, Thomas, 2024, Predatory midges of the genus Schizohelea Kieffer, 1917 in Europe and North Africa (Diptera: Ceratopogonidae), Zootaxa 5514 (2), pp. 169-187 : 170

Genus Schizohelea Kieffer, 1917

Schizohelea Kieffer, 1917: 295 .

Type species Ceratopogon copiosus Winnertz, 1852 (= Ceratopogon leucopeza Meigen, 1804 );

Wirth & Grogan 1988: 78 (diagnosis, synonymy); Szadziewski et al. 2022: 7 (notes on diagnosis, fossil species). Kiefferomyia Mayer, 1937: 303 . Type species Kiefferomyia gorana Mayer, 1937 (= Ceratopogon leucopeza Meigen, 1804 ).

Diagnosis. Moderately large midges with black, shiny body (tarsi slightly lighter) and plane, hyaline wings. Frons and vertex separated by fused eyes in both sexes, narrowly in male, broadly in female ( Fig. 1c ); eyes in both sexes with more or less distinct microtrichia between ommatidia covering the whole surface or restricted to median part only. Female mandible armed with 9–12 strong retrorse teeth. Flagellum without sensilla coeloconica, all 13 flagellomeres separated ( Figs. 1b , 11a ). Female flagellum with distal 5 flagellomeres slightly longer than preceding ones ( Fig. 1b ), antennal ratio AR about 1.0. Male flagellum with 3 distal flagellomeres elongated and with well-developed plume ( Figs. 1a , 11a ). Palpus with 5 segments, palpomere 3 without sensory pit ( Figs. 1d–e , 11b–c ). Paratergite small, anterior anepisternum large, anepisternal cleft narrow ( Fig. 1f ). Wing membrane without macrotrichia except for females of S. incerta ( Clastrier, 1963) ( Fig. 4c ), both first radial cells present, vein M 2 broadly interrupted at base ( Figs. 1g –h ). Legs slender to slightly stout, hind femur usually stout, unarmed except for male S. armata ( Remm, 1993) bearing ventral spines on hind femur ( Fig. 11d ). Tarsomeres 4 subcylindrical to cylindrical. Tarsomere 5 of hind leg with ventral swelling at base in female ( Fig. 2e ), without swelling in male. Fore and mid claws of female short, equal, each with basal inner tooth, hind claw of female single with long basal tooth ( Figs. 2e–f , 11e ); claws of all legs in male short. In male genitalia sternite 9 slightly excavated, tergite 9 short, narrowing distally, gonocoxite with strong 2–3 lobed lateroventral expansion or tubercle at base; gonostylus usually slender, Ccurved, shorter to longer than gonocoxite with proportions 0.7–1.3. Parameres rodlike, separate, with apex bearing a pointed projection and usually a hyaline flap. Aedeagus arched, simple or with two submedian apical projections; dentate ventral plate present in S. incerta and S. clastrieri Szadziewski, Dominiak, Rumišek et Rupp , sp. nov. ( Fig. 5h ). Female abdominal sternite 9 separated medially, with forked or single arms ( Figs. 3e , 11g ), underneath sternite 8 usually well visible internal sclerites of unknown origin ( Fig. 3f ). Two small functional spermathecae with slender necks present, rudimentary spermatheca sometimes well developed ( Figs. 2h , 4h , 11f ).

Comments. Females of the genus are morphologically very similar to each other and cannot be identified with certainty. For example, the shape of single arms of female sternite 9 can vary between specimens. Despite their mandibles being armed with strong teeth, Schizohelea females have never been observed preying on other insects. It is possible that they are facultative predators and feed mostly on flowers (see comments under species).

Figures

FIGURE 1. Schizohelea leucopeza (Meigen, 1804), male (a, d, f, g) and female (b, c, e, h): a, b—flagellum; c—eyes separation; d, e—maxillary palp; f—anepisternum and anepisternal cleft; g, h—wing.

FIGURE 2. Schizohelea leucopeza (Meigen, 1804), male (a) and female (b–h): a—legs; b—foreleg; c—midleg; d—hind leg; e, f—hind tarsomeres 4, 5 and claws; g—genitalia; h—spermathecae.

FIGURE 3. Schizohelea leucopeza (Meigen, 1804), male (a–c) and female genitalia (d–f): a—male genitalia, ventral view; b— parameres; c—aedeagus; d—spermathecae; e—abdominal sternite 9; f—adominal sternite 8 with internal sclerites underneath.

FIGURE 4. Schizohelea incerta (Clastrier, 1963) (a–d) and S. algeriana Szadziewski, Dominiak, Rumišek et Rupp, sp. nov. (e–h): a—male maxillary palp; b—male wing; c—female wing; d—male thorax and legs; e—male wing; f—female wing; g—female genitalia; h—spermathecae.

FIGURE 5. Schizohelea incerta (Clastrier, 1963), male genitalia: a—ventral view; b—lateral view; c—gonocoxal expansions; d, e—parameres; f–h—aedeagus.

FIGURE 11. Schizohelea described by Remm (modified drawings from Remm 1967, 1980, 1993): S. lampropeza (Remm, 1967) (b, e, f, h), S. pekae (Remm, 1980) (a, c, g), S. armata (Remm, 1993) (d); a—male flagellum; b, c—female maxillary palp; d—legs of male; e—female hind claw; f—spermathecae; g—female genitalia; h—female sternite 9.