Eumerus pannonicus Ricarte, Vujić & Radenković, 2016

Markov, Zlata, Nedeljković, Zorica, Ricarte, Antonio, Vujić, Ante, Jovičić, Snežana, Józan, Zsolt, Mudri-Stojnić, Sonja, Radenković, Snežana & Ćetković, Aleksandar, 2016, Bee (Hymenoptera: Apoidea) and hoverfly (Diptera: Syrphidae) pollinators in Pannonian habitats of Serbia, with a description of a new Eumerus Meigen species (Syrphidae), Zootaxa 4154 (1), pp. 27-50 : 31-34

Description of Eumerus pannonicus Ricarte, Vujić & Radenković sp. nov.

Type material. Holotype: 1♂, Srbija, Mokrin , Pašnjaci velike droplje, 21.v.2014, leg. A. Ricarte (EU274) . Paratype: 1♀, Mokrin , SRP, Pašnjaci velike droplje, 11.vi.2014, leg. A. Ricarte (EU276).

The holotype lacks the left meso- and metaleg; the paratype lacks the left meso- and metaleg and the right pro- and metaleg. In all cases, legs were missing because they were taken off for DNA analyses.

Material of other species. Paralectotypes of Eumerus bactrianus Stackelberg : 1♂, Джорф, Дарваз 25.VIII. 943. Штакельберг (‘Džorf, Darvaz Štakelberg’) / Paralectotypus Eumerus bactrianus Stack. (species name handwritten on a red label) / Paratypus Eumerus bactrianus Stackelberg, 1952 (species name handwritten on a red label); 1♀, Таджик. Модеи из Ходжа-оби-Гармаксубальп. 2.–2500 м.Гуссаковский 4.VII. 946 (‘Tadžik. Modei iz Hodža-obi-Garma k subalp. Gussakovskij’) / Paralectotypus Eumerus bactrianus Stack , 52 (species name handwritten on a red label) / Paratypus Eumerus bactrianus Stackelberg, 1952 (species name handwritten on a red label) [ZISP].

The paralectotypes were examined on the basis of high resolution photos of the following parts: head in frontal view; abdomen apex in lateral view (1♂); head in lateral view; metaleg (1♀); male genitalia in all views.

Etymology. The epithet ‘ pannonicus ’ means ‘from Pannonia’ and refers to this species type locality, which is in the Pannonian basin.

Diagnosis. Medium size species (7.2−8.2 mm); eye conspicuously pilose; frontal triangle 1.1x longer than the eye contiguity; basoflagellomere 1.6x longer than wide, bar-shaped, slightly widening towards the apex ( Fig. 2 ); scutum, scutellum and dorsal part of anepisternum black with conspicuous bronze reflections; metafemur moderately swollen, extensively black, with a row of short, black spines ventrally ( Fig. 3 ); metatarsomeres extensively black, only orange at the apex; all terga black; tergum IV with posteriorly-adpressed, orange-yellow, dense pile that provide a distinctive bronze appearance to the abdomen apex; sterna rectangular, conspicuously longer than wide; sternum IV reduced to a circular plate, with a posterior depression; in male superior lobe of surstylus elongate and bifurcated at apex ( Fig. 8 ).

Description. Male. Body length 7.6 mm, wing length 4.9 mm. Head. Eye conspicuously pilose (longest pile about 1.5x longer than a diameter of posterior ocellus), with bare areas near the eye contiguity and near the posterior eye margin ( Fig. 4 ); facets near the eye contiguity larger than those in the posterior part of the eye; in profile, head virtually flat from the posterior ocelli to the posterior edge of the head, gently curved down in the ocellar triangle ( Fig. 5 ); vertical triangle and occiput black with bronze reflections; vertical triangle with a spot of white pollinosity near posterior corner and greyish-white pollinose on the anterior corner; long, erect, orangeyellow pile on the area posterior to the ocellar triangle; ocellar triangle with long, erect, black pile, shorter orangeyellow pile on the anterior corner of vertical triangle; ocellar triangle nearly equilateral; occiput narrowly grey pollinose on the eye margin; frontal triangle 1.1x longer than the eye contiguity; frontal triangle and face white pollinose, with yellowish white pile, more adpressed on the frontal triangle than those on the face; antenna black with sparse silvery pollinosity; basoflagellomere 1.6x longer than wide, bar-shaped, slightly widening towards the apex ( Fig. 2 ); antennal arista black. Thorax. Scutum, scutellum and dorsal part of anepisternum black with conspicuous bronze reflections, the reminder of the pleuron shiny black with sparse white pollinosity; scutum and scutellum with orange-yellow pile, longer and curved at the posterior margin of scutellum; scutum with two white pollinose vittae extending for the anterior three quarters of the scutum length; scutum with a row of black setulae above the wing insertion; posterior margin of scutellum slightly serrated; profemur extensively black, only orange at the very base and apex; basal third and apex of all tibiae orange; protarsus black dorsally and orange ventrally; meso- and metafemora extensively black, only orange at apex; dorsal surface of mesobasotarsomere orange basally and apically, mesotarsomeres 2–5 orange apically; mesotarsus orange ventrally; metafemur moderately swollen, with a row of short, black spines ventrally, on the apical three quarters of the femur length; metatarsomeres extensively black, only orange at the apex; metabasotarsomere longer than metatarsomeres 2–4 together; wing extensively microtrichose, with a small bare area on the cell bm basally; calypter white; halter yellowish white. Abdomen. All terga black, with much weaker bronze reflections than those on scutum; terga II and III with black pile centrally and white to yellowish-white pile laterally; tergum IV with posteriorly-adpressed, orange-yellow, dense pile that provide a bronze appearance to the abdomen apex; terga II–IV with two bar-shaped, whitepollinose, oblique fasciae not reaching the lateral margins of terga (fasciae on terga II and III slightly curved, on tergum IV straight and shorter than those on the terga II and III); sterna conspicuously longer than wide, surrounded all around by membrane in sterna II–IV (except for sternum IV posteriorly); in ventral view, abdomen with pleural membrane extending for about two thirds of the abdomen width (the remainder third corresponds to the sternum); sterna and pleural membrane brownish black; sterna II and III with long, erect, yellowish-white pile; sternum IV reduced to a circular plate, with a posterior depression bearing orange-yellow pile at and near the margin. Genitalia ( Figs 6–8 ). Superior lobe of surstylus elongate and bifurcate at apex; cercus elongate; inner part of hypandrium with a circular indentation basally.

Female. Body length 7.2−8.2 mm, wing length 5−5.3 mm (n=2). Same as male except for the following characters: frons white pollinose on the eye margin and with a pollinose macula on the area anterior to the ocellar triangle ( Fig. 9 ); frons with laterally-adpressed, yellowish-white pile; scutum with an additional, central, narrow, white-pollinose vitta extending for a variable length; sternum IV rectangular, longer than wide.

Taxonomix notes. The male holotype of E. pannonicus sp. nov. keys out to E. bactrianus in the key of Stackelberg (1961). However, it can be readily separated from that species because in E. bactrianus the metabasotarsomere is, at most, slightly longer than tarsomeres 2 and 3 together, while in E. pannonicus sp. nov. the metabasotarsomere is longer than tarsomeres 2–4 together. In addition, the new species can be separated from the similar E. bactrianus by the following characters: in E. pannonicus sp. nov. the basoflagellomere is bar-shaped ( Fig. 2 ), while in E. bactrianus is axe-shaped in male (see Stackelberg 1961: figure 21.2) and more oval-shaped in female (paralectotype); in E. bactrianus the dorsal part of metatarsomeres 2–4 is orange (female paralectotype), while in E. pannonicus sp. nov. is at most, orange apically; in the male genitalia of E. pannonicus sp. nov. the superior lobe of surstylus is longer than that in E. bactrianus ( Fig. 8 ), which has it bulge-shaped basally (see Stackelberg 1961: figure 21.3). Eumerus bactrianus was described from the mountain ranges of Gissar and Darvaza, Central Asia ( Stackelberg 1952). Eumerus bactrianus is also listed in the fauna of Israel ( Kaplan 1974, unchecked records). That closely related species ( E. bactrianus and E. pannonicus sp. nov.) occur in geographically widely separated areas.

Habitat. Specimens were caught on the white flowers of Conium maculatum (Apiaceae) , on track side vegetation, within a typical Pannonian steppe.

Range. Northern Serbia (Vojvodina).

Figures

FIGURE 9. Eumerus pannonicus Ricarte, Vujić & Radenković sp. nov., female paratype: head, dorsal view.

FIGURES 2 – 8. Eumerus pannonicus Ricarte, Vujić & Radenković sp. nov., male holotype. 2: right antenna, inner view; 3: right hind leg, lateral view; 4: head, dorsal view; 5: head, lateral view; 6: male genitalia hypandrium, lateral view; 7: male genitalia, epandrium, lateral view; 8: male genitalia, right surstylus, lateral view.