Empis Linnaeus, 1758

Daugeron, Christophe, 2009, Systematics of the Euro-Mediterranean Empis (Kritempis) (Diptera: Empididae: Empidinae) *, Zootaxa 2318, pp. 531-544 : 532-533

Genus Empis Linnaeus, 1758 subgenus Kritempis Collin, 1926

Kritempis Collin, 1926: 236 (as subgenus of Empis Linnaeus, 1758 ). Type species: Empis algira Macquart, 1838: 275 (original designation).

Monophyly and included species. Collin (1926) included in his new subgenus Kritempis five chiefly Mediterranean species, namely E. algira Macquart , E. macquarti Becker (= E. geniculata Macquart ), E. nigrimana Becker , E. sibillina Bezzi and E. macropalpa Egger , as well as the European species E. livida Linnaeus , especially on account of the considerable development of the male cercus (dorsal lamella sensu Collin). Empis macquarti , E. nigrimana and E. sibillina were arranged as “unplaced species of Empis ” in the Palaearctic catalogue by Chvála and Wagner (1989), on account of their male genitalia apparently very different from the type-species E. algira ( Chvála 1994) . Chvála and Wagner (1989) added to Kritempis the species E. hoffmannseggii Loew from Portugal and Northern Italy ( Raffone 2008: 109) for which Chvála examined the holotype in 1986 (ZMHU); later, Chvála (1994) suggested that E. hoffmannseggii had rather a close affinity with the subgenus Euempis Frey, 1953 , but did not re-assign the species to this subgenus.

Exclusive of E. livida , I reviewed the type material of all the above species, including E. hoffmannseggii Loew , and studied in detail the male genitalia. The hypandrium is reduced to a pair of well sclerotized lateral arms, with the ventral part absent ( Figs 1-5, 8-9). The reduction of the hypandrium occurred in several other species groups (e.g., the Empis (Coptophlebia) hyalipennis -group) within the Empidinae but not in groups narrowly related to Kritempis (i.e. subgenera Leptempis Collin, 1926 and Planempis Frey, 1953 see below). This character is found in all species given above, exclusive of E. hoffmannseggii , and is thus considered synapomorphic for them.

In addition, in all available females, the mid tibia is somewhat twisted, bent with a posteroventral group of short spine-like setae at basal tip ( Fig. 6). This character is considered a second synapomorphic character for those species.

In all the studied species, exclusive of E. hoffmannseggii , the anal vein (A 1) is faint, incomplete and sometimes not visible ( Fig. 7; Collin 1961: fig. 169). Generally the abbreviation of the anal vein is linked to the presence of a not well developed anal lobe. The anal lobe is strongly developed in Kritempis and the presence of a faint anal vein could be an additional autapomorphic character for the subgenus.

Chvála (1994: 44) was mistaken in believing that the dorsal lamella (= cercus) of the male hypopygium of E. macquarti Becker is small; actually the male cercus of this species is considerably developed ( Fig. 2) as in all other species ( Figs 1, 3-5, 8-9) (exclusive of E. hoffmannseggii ) as already stated by Collin (1926, 1961); however the cercus is also much broader than the epandrial lamella in the subgenera Leptempis and Planempis , and should be considered a synapomorphic character for all species belonging to Kritempis , Leptempis and Planempis ( Daugeron et al. 2002) , and not only for species of Kritempis alone.

Empis hoffmannseggii actually belongs to the polyphyletic subgenus Coptophlebia Bezzi (vein M 1 abbreviated), and according to the structure and shape of male hypopygium as well as the presence of ventral setae on the prosternum, could have a close affinity to E. (E.) pilosa and other related species of the subgenus Empis (see Syrovátka 1980, 1991).

Finally, Collin’s (1926) original views are here followed, and I include in the subgenus Kritempis the following species: E. algira Macquart , E. livida Linnaeus , E. macquarti Becker , E. macropalpa Egger , E. nigrimana Becker , E. sibillina Bezzi as well as two new species, namely E. sardoa sp. nov. (Sardinia) and E. taffertensis sp. nov. ( Morocco).

Diagnosis. Male with holoptic eyes, upper ommatidia enlarged, postgena with fine pale yellow setae, proboscis about as long as head height, labella thick. Prosternum with numerous lateral pale yellow setae, bare ventrally, laterotergite with fan of pale or golden yellow setae ( E. livida Linnaeus has also an anterior row of black setae on laterotergite); 1 and 4 strong, long postalar and scutellar setae respectively. Wing with anal lobe well developed, Sc abbreviated, R 4+5 forked, A 1 faint, incomplete. Hypopygium with cercus considerably developed, distinctly broader than epandrial lamella; hypandrium reduced to pair of lateral arms; phallus generally long, rather thick basally, more or less undulated, always with specific shape. Female similar to male except for following characters: eyes dichoptic with all ommatidia subequal, frons as wide as face, mid tibia somewhat S-shaped or bent bearing a ventral or posteroventral group of short spine-like setae at base.

Discussion. Within the subfamily Empidinae , Kritempis belongs to a monophyletic group of subgenera, namely Euempis , Leptempis , Pachymeria Stephens, 1829 Planempis and Polyblepharis Bezzi, 1909 ( Daugeron et al. 2002). The combination of the following characters allows distinguishing Kritempis from the remaining subgenera: A 1 faint, abbreviated, male cercus considerably developed but not bilobed, hypandrium reduced, ventrally absent, presence of posteroventral group of short spine-like setae on female mid tibia basally. It must be noted that the abbreviation of the median veins M 1 and / or M 2 is not a diagnostic character since it is only found in three species: E. algira , E. livida and E. macropalpa .

Chorotype. Euro-Mediterranean. Kritempis is mainly distributed around the Mediterranean basin; recorded from North Africa ( Algeria and Morocco), Corsica, Sardinia, Sicily, and mainland Italy. Only E. livida Linnaeus is widely distributed, known from Europe to North Africa ( Algeria), where it is newly recorded.