Rhinoceromyia Grichanov, 2024

Grichanov, Igor Ya., 2024, Rhinoceromyia, a peculiar new genus of long-legged flies from Guinea (Diptera: Dolichopodidae: Dolichopodinae), Zootaxa 5471 (4), pp. 489-495 : 490

Rhinoceromyia Grichanov gen. nov.

urn:lsid:zoobank.org:act:6F400745-0203-49C0-962A-DAB837B4C084

Type species. Rhinoceromyia dubrovskii Grichanov sp. nov.

Etymology. The genus is named via Latin rhīnocerōs, from Ancient Greek ῥῑνόκερως (rhīnókerōs, “nose-horned”) and from Ancient Greek μυῖα (muîa, “fly”). The gender is feminine.

Diagnosis. The generic diagnosis is based on a single species, and notes characters considered to be of generic importance; however, a complete species description is also provided below.

Rhinoceromyia gen. nov. is included in the subfamily Dolichopodinae because of a dorsally setose scape; mid and hind femora with one distinct preapical seta on anterior surface; wing vein M 1 reaching wing margin near apex; male abdominal tergite 6 with several fine setae; segment 7 bare; hypopygium relatively large and projecting forward under abdomen (after Brooks 2005).

The following character states place Rhinoceromyia gen. nov. in the Ortochile genus group (sensu Brooks 2005): mid femur with 1 strong posteroventral preapical seta in addition to fine terminal posteroventral seta; hypandrium fused with the epandrium. Absence of the basiventral epandrial lobes excludes Rhinoceromyia gen. nov. from the Sybistroma Meigen + Hercostomus longiventris lineage. The new genus is somewhat close to the subgroup that includes Afrohercostomus Grichanov , Ortochile Latreille , Poecilobothrus Mik , and Parahercostomus Yang, Saigusa et Masunaga (sensu Brooks 2005), as well as Afropelastoneurus Grichanov and Setihercostomus Zhang et Yang.

The following characters readily distinguish Rhinoceromyia gen. nov. from all dolichopodine genera: antennae inserted close to ocellar tubercle in both sexes, with frons much wider than high ( Figs 1B , 3B ); lower half of male face with large conoid horn bearing two brushes of setae at apex ( Fig. 1C ); male cercus secondarily segmented, with distal section of cercus articulated with basal section ( Fig. 2A ); epandrium with distodorsal lobe supporting distal section of cercus ( Fig. 2C ).

The use of available keys to dolichopodid and dolichopodine genera leads Rhinoceromyia gen. nov. to Pelastoneurus Loew ( Bickel 2009) or Hercostomus Loew ( Grichanov & Brooks 2017; etc.). Nevertheless, the new genus is closest in habitus to Afropelastoneurus ; all species of both genera have long sparse pubescence on arista-like stylus, similar body and leg setation and similar morphology of hypopygium. Rhinoceromyia gen. nov. differs from Afropelastoneurus by the following features: arista-like stylus somewhat shifted on outer surface of postpedicel, mostly black, white in basal third or quarter ( Figs 1D , 3A ); face rather broad with bulging clypeus in both sexes ( Figs 1B , 3B ); proboscis projected; mesonotum without distinct spots; acrostichal setae uniserial between anterior two pairs of dorsocentrals; katatergite (in front of posterior spiracle) without cluster of setulae; cercus bisegmented ( Fig. 2C ); postgonite broad and parallel-sided to apex (dorsal view). Five species of Afropelastoneurus were described and illustrated ( Grichanov 2004, as Paracleius Bigot ) with arista-like stylus black, not shifted onto outer surface of postpedicel; face narrow in male and broad in female, clypeus weakly bulging; proboscis normal; mesonotum with distinct dark spot above notopleuron; acrostichal setae biserial, sometimes irregular; katatergite with a cluster of setulae; cercus simple; postgonite narrow. Some species of Afropelastoneurus have brownish wings with a hyaline transverse stripe just behind vein dm-m.

The complex set of characters supports the generic status of Rhinoceromyia gen. nov.

Figures

FIGURE 1. Rhinoceromyia dubrovskii sp. nov., male holotype in ethanol (A, B, D, E) and dried (C, F). A. Habitus. B. Head, lateral view. С. Facial horn, clypeus and palpus, lateral view. D. Antenna, lateral view. E. Wing. F. Hypopygium, dorsolateral view. A, B, D, E—in ethanol; C, F—dry.

FIGURE 2. Rhinoceromyia dubrovskii sp. nov., male genitalia of paratype after maceration. A. Hypopygium, lateral view. B. Apex of hypopygium, ventrolateral view. C. Apex of epandrium and cercus, dorsolateral view. D. Cercus, dorsal view.

FIGURE 3. Rhinoceromyia dubrovskii sp. nov., female paratype in ethanol. A. Head, lateral view. B. Head, anterior view. C. Apex of abdomen, lateral view, with inset showing terga 9+10, dorsal view.