Spilogona azorensis, Michelsen, 2021

Michelsen, Verner, 2021, Macaronesian Muscidae (Diptera). III. First record of the genus Spilogona Schnabl based on two new endemic species from the Azores and Madeira, Zootaxa 4952 (1), pp. 128-134 : 129

Spilogona azorensis sp. nov.

( Figs 1A, B , 2A, B )

Limnophora sp.; Frey 1945: 103 (Azores).

Material examined. Type material [ MZH]: Holotype ♀: AZORES: Terceira, Santa Barbara [38.70N 27.34W], 7.vii.1938 ( R. Frey) . Paratypes: AZORES: Terceira, Santa Barbara, 4♀ 7.vii.1938 ( R. Frey). São Miguel, Lagoa de Fogo [37.75N 25.47W], 1♀ 2.viii.1938 ( R. Frey) .

Description. Female ( Figs 1A, B ). Medium sized, wing length 4.4‒5.0mm (n=6). Head, including prementum, grey to bluish grey pruinose, suffused with brown on vertex, fronto-orbital plates and frontal triangle; frontal vitta darker, brownish black; parafacial plates silvery grey with a golden brown tinge. Thorax covered in dense bluish grey pruinosity except dark brown on upper part of anepisternum and on five mesonotal stripes that tend to merge for some distance behind the suture; only the acrostichal stripe reaches the scutellum. Wing membrane smoky brown; calypteres concolorous, notably dark brown at margins; halter yellow with blackish head. Legs black, all femora bluish grey pruinose. Abdomen matt bluish grey pruinose except for dorsal part of tergite II and large paired trapezoid marks on tergites III and IV being shiny dark brown. Postpedicel c. 2 times as long as wide, anterior apical corner forming an obtuse angle; arista short-pubescent, longest branches subequal to its greatest basal diameter. Haustellum conical, short and thick. Broad frons widening towards lunule; frontal vitta parallelsided, frontal triangle not quite reaching lunule. Frons and lower facial margin slightly and equally projecting. Fronto-orbital plate with 1 reclinate orbital seta about same size as outer postvertical seta, 4‒5 robust inclinate frontal setae without interspatial setulae, but bordered laterally by an irregular row of setulae. Mesonotum sparsely beset with ground setulae. Dorsocentral setae 2 + 3(‒4); presutural acrostichal field with 4‒10 setulae arranged in two very close-set rows leaving broad bare stripes toward adjacent dorsocentral setae. Notopleuron without setulae. Anepisternum without interspatial setula(e). Katepisternal setae 1 + 1. Scutellum with 1 setula on upper, preapical border of declivity. Vein C (as usual) without setulae dorsally; spines at subcostal break inconspicuous. Fore tibia with 1 p seta below middle. Mid femur without subapical ad seta, in basal half with 4‒6 pv setae; mid tibia before apex with 2 strong pd setae only. Hind femur with av row of setae decreasing in size towards base, in basal part with a variable number of short and fine pv setae; hind tibia with 1‒2 av, 3(‒4) ad setae, without distinct pd seta. Abdomen with modest-sized discal and hind marginal setae. Sternite I bare. Ovipositor ( Figs 2A, B ) rather short and thick; segment VI with fine hind marginal setae uniserial, tergite VI widely membranous dorsally; segment VII with hind marginal setulae uniserial; tergite VII complete, dorsal part extended, convex on apodemal basal part; tergite VIII a pair of lateral, triangular bare plates; sternite VIII pieces each with 3 larger and 2 smaller spine-like setulae on hind part; epiproct short, with single pair of long wavy setulae; cerci a pair of shorter than deep, slightly convex plates, with 2 longer, wavy setulae and several much shorter ones; bell-shaped hypoproct with 3 pairs of up-curved, spine-like setulae and 2 pairs of wavy setulae.

Male. Unknown.

Relationships. The following combination of character states may help to distinguish female S. azorensis from females of other similar species of Spilogona found in Europe: haustellum thick, prementum pruinose; 1 orbital seta; presutural acrostichal field with setulae in two close-set rows; notopleuron without setulae; anepisternum without interspatial setula(e); 1 + 1 katepisternal setae; fore tibia with submedian p seta; mid femur with 4‒6 pv setae in basal half; mid tibia with 2 pd setae only; halter yellow with blackish knob; sternite I bare; hypoproct with spinelike setulae.

Distribution. Apparently endemic to the Azores ( Portugal).

Figures

FIGURE 1. Spilogona azorensis sp. nov. Female holotype: lateral habitus (A); head and anterior mesonotum in dorsal view (B).

FIGURE 2. Spilogona azorensis sp. nov. Ovipositor in lateral (A) and ventral (B) aspects.