Empis (Enoplempis) fisheri, Sinclair & Brooks & Cumming, 2025

Empis (Enoplempis) fisheri sp. nov.

urn:lsid:zoobank.org:act:66CD1D6E-2EEE-4C88-BCE4-1C34D17BDD0C

( Figs 176–178 View FIGURES 176–180 , 183, 184 View FIGURES 183–185 , 192 View FIGURES 192–193 )

Type material. HOLOTYPE ♂, labelled: “USA: CA: El Dorado Co. / El Dorado Hills, New York / Creek , 680 ft. 38°41′43″N,/ 121°04′38″W E.M. Fisher / IV.20.2002”; “El Dorado Hills/ IV-20-2002 / ♂ swarm, ea. w/ balloon, w/o prey”; “ HOLOTYPE / Empis (Enoplempis) / fisheri Sinclair ,/ Brooks & Cumming [red label]” ( CSCA) GoogleMaps . PARATYPES: USA. California: El Dorado County: Same data as holotype (1♂ with balloon without prey, 2♂, CNC; 2♂ with balloon without prey, 2♂, CSCA); same data as holotype except, 21.vi.2002 (1♂ with balloon without prey, CNC; 1♂, CSCA); El Dorado Hills , New York Ck , 22.iii.1998, in swarm, each with balloon, E.M. Fisher (2♂, CNC; 2♂, 1♂ with balloon without prey, CSCA); El Dorado Hills, N. York Ck, 700 ft, 18–20.iv.2002, male swarm, each w/ white balloon w/o prey (4♂, CNC; 3♂ CSCA); El Dorado Hills, 38°41′43″N 121°04′44″W, 222 m, 24.iii.2003, J. & A. Skevington (1♂, CNC) GoogleMaps . Placer County: 4 km NE Auburn at American R, 38.9164°N 121.0392°W, 563 ft, 6.vi.2012, G.W. Forister (2♂, 2♀, UCDC) GoogleMaps .

Diagnosis. This species is distinguished from other species of the E. (En.) geneatis species group by the absence of long setae on the face, palpus or antenna ( Fig. 177 View FIGURES 176–180 ), male hindleg with lobes and modified setae ( Fig. 178 View FIGURES 176–180 ), hind tibia somewhat clavate with expanded hind tarsomere 1, and the male cercus is narrower than epandrium, projecting horizontally.

Description. Wing length 3.3–3.6 mm. Male. Similar to E. (En.) geneatis , except as follows: head with face without setae ( Fig. 177 View FIGURES 176–180 ). Ocellar triangle elevated, grey pruinescent, with pair of thin ocellar setae, longer than pprn; posterior setulae half length of ocellars. Occiput bearing slightly arched setae on upper half; thinner, wavy setae posterior to mouth opening; bare posterior to ocellar triangle. Scape 2× longer than pedicel, with short setulae, at most subequal to width of scape; pedicel with normal circlet of setulae; postpedicel long and tapered, 5× longer than basal width; stylus 1.5× basal width of postpedicel. Palpus black, with short setae.

Thorax dark brown in ground-colour, densely grey pruinescent. Scutum with pair of distinct greyish vittae between acr and dc rows (viewed anteriorly or posteriorly). Proepisternum with short setae on lower section; upper proepisternum in front of spiracle without setae. Postpronotum with 1 long seta and several shorter, silky setae. Scutum with long bi-serial acr, increasing in length posteriorly; dc multi-serial, similar to acr, increasing in length posteriorly; 2 posterior npl, with several shorter anterior npl; 1 presut spal and several long, silky setae; 1 psut spal and several long, silky setae; 1 pal. Scutellum with pair of long sctl, with 2–3 pairs of shorter marginal setae; disc bare. Laterotergite with numerous long, pale setae.

Legs short, slender, entirely dark brown ( Fig. 176 View FIGURES 176–180 ). Coxae with pale setae, shorter than length of coxae. Leg setae mostly pale. Fore femur with fine, erect posterior setae. Fore tibia with fine, erect posterior setae; ventrally with fine, dense setae, length less than half width of segment, continuing on tarsomeres. Fore tarsomere 1 not broader than apex of tibia; all tarsomeres without spine-like ventral setae; tarsomeres 2–3 with apicolateral pair of spine-like setae, not longer than width of segment. Mid femur with similar setae to fore femur, longer dorsally and anteriorly. Mid tibia with several erect anterodorsal and posterodorsal setae; ventrally with long, dense setae, longer than twice width of tibia. Mid tarsomeres 1–3 with several pairs of strong ventral setae, shorter than width of tarsus; tarsomeres 1–3 with apicolateral pair of spine-like setae, shorter than width of segment. Hind femur slender, clothed in fine ventral setae, shorter than width of femur; longer anterior and dorsal setae on basal half; short anteroventral tubercle with dark, sharp semi-circular ridge; posteroventral tubercle distal to anteroventral tubercle, with radiating row of 5–8 pale setae, longer than length of tubercle ( Fig. 178 View FIGURES 176–180 ). Hind tibia somewhat clavate, with sub-basal ventral swelling, truncate with ridge of long posteroventral setae; dorsal setae shorter than width of tibia ( Fig. 178 View FIGURES 176–180 ). Hind tarsomeres distinctly swollen, narrower than apex of tibia, with strong ventral setae; tarsomeres 2–5 similar to mid tarsus.

Wing clear with dark veins; veins mostly well sclerotized, CuA+CuP very weak, not reaching wing margin.

Abdomen dark brown, thinly pruinescent to shiny, with long, pale wavy setae on tergites and sternites of segments 1 and 2. Terminalia ( Figs 183, 184 View FIGURES 183–185 ): dark brown. Cercus narrower than epandrium, subtriangular, tapering posteriorly to rounded apex; fused anterolaterally with epandrium; dorsal margin straight; length of setae about same as width of cercus. Subepandrial process extended to phallus; apex arched ventrally. Epandrial lamella subtriangular, posterior margin projecting beyond cercus, bearing apical setae, slightly longer than cercal setae; apex broadly rounded, not upturned. Hypandrium longer and wide along posterior margin; apex tapered, less than half as long as epandrium; several short setae present. Phallus ( Fig. 184 View FIGURES 183–185 ) with base not greatly expanded, with pair of slender processes beyond mid-length; apical section abruptly curved beyond epandrium, with numerous lateral setulae; apex of wide dorsal opening; ejaculatory apodeme short, less than half-length of epandrium, with narrow horizontal wings ventrally.

Female. Similar to male, except as follows: frons as broad as antennal sockets, with short setulae along eye margin; legs similar to male, without tubercles on hindleg; cercus long and slender, subequal to length of tergite 8.

Geographical distribution and seasonal occurrence ( Fig. 192 View FIGURES 192–193 ). Empis (En.) fisheri is known from March to June in El Dorado and Placer Counties in California.

Etymology. This species is named in honour of the collector of most of the type series, Eric M. Fisher, formerly of the California State Collection of Arthropods (CSCA).

Nuptial gift presentation. Males have been observed in swarms each carrying a relatively small white balloon, without prey (see “ Type material” above). The balloons appear to collapse after collection.

Remarks. This species has been collected in March and April, together with swarms of E. (En.) bigoti . Empis (En.) fisheri is tentatively assigned to the E. (En.) geneatis group, on the basis of similarly long acrostichal and dorsocentral setae, holoptic male with upper facets enlarged, and shape of hind tibia and tarsomeres. This species differs from the other two species of this group by the absence of long setae on the head and modified male hindleg.