Platypalpus Macquart

Shamshev, Igor & Grootaert, Patrick, 2012, Proposed change in status of the Nearctic genus Charadrodromia Melander (Diptera: Hybotidae, Tachydromiinae), with description of four new species, Zootaxa 3525, pp. 35-50 : 36

Genus Platypalpus Macquart

Coryneta Meigen, 1800: 27 . Type species: Musca cursitans Fabricius, 1775 (by subsequent designation of Engel 1939: 43). Suppressed by I.C.Z.N. 1963: 339 (Opinion 678).

Platypalpus Macquart, 1827: 92 . Type species: Musca cursitans Fabricius, 1775 (by subsequent designation of Westwood 1840: 132).

Phoroxypha Rondani, 1856: 146 . Type species: Tachydromia longicornis Meigen, 1822 (by original designation).

Cleptodromia Corti, 1907: 101 (as subgenus of Tachydromia ). Type species: Tachydromia (Cleptodromia) longimana Corti, 1907 (by monotypy).

Brevios Brunetti, 1913: 22 . Type species: B. longicornis Brunetti, 1913 (by original designation).

Howlettia Brunetti, 1913: 23 . Type species: H. flavipes Brunetti, 1913 (by monotypy).

Charadrodromia Melander, 1928: 292 . Type species: C. microphona Melander, 1928 (by original designation), syn. nov.

Tachydromia , authors, not Meigen, 1803, misidentifications.

Notes on synonymy. When examining type materials of the species assigned to Charadrodromia we found that actually they belong to the genus Platypalpus Macquart. Melander (1928) did not provide any comparative analysis of Charadrodromia but his key to the genera and subgenera of the Tachydromiinae (l.c.: 270) indicates diagnostic features that Melander thought to be crucial to erect a separate genus: first basal cell equal to or longer than the second, anal cell not formed; face narrower than frons; two pairs each of ocellar and vertical bristles; arista apical; humeri constricted; legs not evidently bristly; cheeks linear; notum with coarse hairs but no strong anterior dorsocentrals.

It is evident that none of the characters applied by Melander could be used to distinguish Charadrodromia from Platypalpus . Relative lengths of cells br and bm of the wing (= first and second basal cells) are quite variable in Platypalpus including North American species (e.g., Chillcott 1962: 117, figs. 8–10; Chvála 1975: figs 674–747). In Platypalpus the anal cell (or cell cu p) is usually closed (anal vein distinct basally) but rarely (e.g., some species of the P. hackmani group) it is not quite formed (anal vein wanting or evanescent basally). Furthermore, the anal vein is distinct in C. arnaudi (cf. Fig. 2 ) and evanescent in other species of Charadrodromia ( Figs. 6 , 7 ). Finally, the length of ocellar bristles varies in Platypalpus and even in Charadrodromia . Consequently, Charadrodromia is viewed here as a junior synonym of Platypalpus .

The genus Chersodromia from which Charadrodromia was distinguished in Melander’s key belongs to the tribe Drapetini that is diagnosed by several distinctive apomorphies ( Sinclair & Cumming 2006: 79). Unfortunately Melander's (1928) misleading key (p. 270, couplets 6 and 7) to the genera and subgenera of the Tachydromiinae was applied in the Manual of Nearctic Diptera ( Steyskal & Knutson 1981) .

Figures

FIGURE 6. Platypalpus microphona (Melander), habitus, female (paralectotype), lateral view.

FIGURES 1 – 5. Platypalpus arnaudi (Melander), male. 1. habitus, lateral view. 2. wing, dorsal view. 3. right epandrial lamella, lateral view. 4. epandrium with cerci and hypoproct, dorsal view. 5. left epandrial lamella and left cercus, lateral view.

FIGURES 7 – 11. Platypalpus syletor (Melander). 7. apical part of right epandrial lamella, ventral view. 8. right epandrial lamella, lateral view. 9. cerci and epandrium, dorsal view. 10. left epandrial lamella, lateral view. 11. habitus, female (holotype), lateral view.