Eumerus grallator Smit

Grkovic, Ana, Smit, John, Radenkovic, Snezana, Vujic, Ante & Steenis, Jeroen van, 2019, Two new European long-legged hoverfly species of the Eumerusbinominatus species subgroup (Diptera, Syrphidae), ZooKeys 858, pp. 91-108 : 94-98

Eumerus grallator Smit sp. nov. Figs 3A, B; 4E; 5A, B, D, G

Type material.

Holotype. SPAIN ♂, Castilla la Mancha , Villahermosa. Original label: “España, Castilla / la Mancha, Villahermosa / [UTM] 30S WH19329-88405 / 23.vi.2003. 980 m / leg. J.T. Smit ". The holotype is in good condition with no apparent signs of wear, except for wingtips, which are both damaged. The holotype is deposited in the NBC . Paratypes. SPAIN • 1 ♂ same data as for holotype ( NBC) ; 1♀, Andalusia, Los Marines , 600 m, 37°17'05"N 06°22'08"W, 10.vi.2015, leg. J. and I. Smit ( NBC) ; 1♀, Foia Ampla, 1060 m, Agres, Alicante , 3-17.vii.2001, leg. Pérez-Bañon, Marcos-García y Rojo ( FSUNS) ; 1♀, Foia Ampla, 1060 m, Agres, Alicante , 2-16.vii.2002, leg. Pérez-Bañon, Marcos-García y Rojo ( CEUA) ; 1♂, Mas del Parral, 900 m, Bocairent , Valencia, 5-19.vi.2001, leg. Pérez-Bañon, Marcos-García y Rojo ( FSUNS) ; 1♂, "FO: 5335 Spanien / 36°58'29"N, 04°00'59"W / Bosque del Puerto Navazo, Alhama de / 1180 m NN / A; Thapsia villosa / leg. A. Ssymank, 12.06.2003 " ( DDPC) ; 1♂, “España, Madrid, Aranjuez / UTM 30T 4484430, 545 m a.s.l. / 17.vi.2015, leg. P.A. Fidalgo " ( AEPC) ; 1♂, “España, Burgos, Peñahorada / UTM 30T 4474705, 910 m a.sl. / 13.vii.2016, leg. P.A. Fidalgo " ( AEPC) ; 2♂ “España, Soria, Herrera de Soria / UTM 30T 4984624 1095 m a.s.l. / 14.vii.2016, leg. P.A. Fidalgo " ( AEPC) .

Diagnosis.

Male. Ocellar triangle isosceles. Basoflagellomere blackish, small, rounded, with one or two short radial wrinkles. Constriction of elongated metafemur located in posterior half (Fig. 4E). Greatest width of metafemur is approximately equal to one fifth of length of metafemur. Metatibia noticeably shorter than metafemur. Abdomen black, without red markings. Ventral margin of hypandrium with medial triangular protuberance (Fig. 5D: vp). Anterior lobe of surstylus with a single pilose row (Fig. 5A).

Description.

Male. Body length (excluding antenna): 11.5 mm; wing length: 7 mm. Head. Eyes separated by the width of an ocellus and covered in dense white pilosity. Eye margins in anterior view almost parallel, slightly broadening ventrally. Face completely black pilose, covered in silver pollinosity, most expressed in middle. Frons, vertical triangle and occiput black; silver pollinosity well expressed along eye margin on frons, on vertex anteriorly and dorsally on occiput behind eye margin, but most distinctive laterally. Ocellar triangle isosceles and predominantly black pilose, becoming intermixed with white pile in front of ocellar triangle and turning predominantly white behind it. Distance from anterior to posterior ocellus same as distance from latter one to upper eye corner. Lower facial margin in lateral view not protruding. Scape and pedicel brown to black. Basoflagellomere dark brown, rounded and slightly longer than broad with one or two short radial wrinkles. Ventral pile of pedicel black, not longer than its depth. Thorax. Scutum and scutellum densely punctate, shiny, with a bluish tinge; covered in long dense white pilosity. Two vittae of white pollinosity on scutum faint and thin, hardly reaching base of wings. Pleurae black. Anepisternum entirely white pilose, except for some black pile just behind the anterior spiracle. Anepimeron white pilose with some black pile posteriorly. Katepisternum and katepimeron black pilose. Wing. Hyaline with pterostigma about same color as the wing. Vein R4+5 slightly curved. Wing covered in microtrichia except for basal cells mostly bare. Costal setae black. Halter blackish. Legs. Metaleg slender with all segments very elongated (Fig. 4E). Femora black, yellowish posteriorly, covered in black pilosity. Pro- and mesofemur black with yellowish tips; metafemur black, turning lighter in apical third, becoming orange at apex; slightly thickened in basal half; with a few scattered black setae in apical half. Tibiae white pilose. Pro- and mesotibia mostly black, yellowish in basal third and with yellowish apices; metatibia in basal half yellowish, apical half black turning lighter towards apex. Metatibia slightly thickened apically and slightly curved in apical half (curvature being species-specific in all three species with black abdomen). Tarsi brown to black; basitarsus of metaleg lighter ventrally; metatarsus longer than tibia (Fig. 4E). Abdomen. Black, punctate, pilose, tapered (Fig. 3A). Terga 2-3 with pairs of wide white pollinose maculae, slightly obscured towards medial part of terga; tergum 4 with pair of white pollinose maculae with apices upwards. Tergum 2 with long white pile laterally; pilosity adpressed, in area of pollinose maculae white, black on rest of terga. Punctation is visible through pollinose maculae. Genital capsule covered in erect black pilosity. Sterna entirely black pilose; sternum 4 flat with longer pilosity apico-laterally (Fig. 5G). Terminalia. (Fig. 5A, B, D). Posterior surstyle lobe simple, beak-like in lateral view, with long strong setae laterally on outer surface (Fig. 5A: ps); in ventral view, outer margin convex, pilose (Fig. 5B: om). Cerci oval, slightly pointed apico-dorsal, uniformly pilose (Fig. 5A: c). Interior accessory lobe of surstyle lobe densely pilose (5B: in). Hypandrium curved, broad with folded thecal ridge near base; medially with triangular protuberance on ventral margin (Fig. 5D: vp), and wide notch dorsally near base. Female. Body length (excluding antennae): 11.5 mm; wing length: 7 mm. Similar to male except normal sexual dimorphism and for following differences: Head. Entirely white pilose. Basoflagellomere oval, with three to four radial wrinkles. Width of frons in narrower part is less than one fourth of width of head in anterior view. Thorax. White pollinose vittae obscured. Pleurae white pilose. Segments of metaleg only slightly elongated. Abdomen. Tergum 4 with longer white pile posteriorly. All sterna white pilose.

Etymology.

The specific epithet is the Latin word grallator meaning "one who walks on stilts", which refers to the very slender and elongated legs of this species. It should be treated as a noun in apposition.

Distribution.

Spain.

Remarks.

The male holotype and one male paratype specimens were swept from a stand of some large yellow Apiaceae along a road, in an open park-like landscape of an oak dehesa. Accompanying hoverfly species were Eristalinus taeniops (Wiedemann, 1818), Eristalis arbustorum (Linnaeus, 1758), Eumerus barbarus (Coquebert, 1804), E. nudus Loew, 1848, Spilomyia digitata (Rondani, 1865) and Xanthogramma marginale (Loew, 1854).