Rhopalosyrphus (s.s.) ecuadoriensis Reemer

Reemer, Menno & Stahls, Gunilla, 2013, Generic revision and species classification of the Microdontinae (Diptera, Syrphidae), ZooKeys 288, pp. 1-213 : 114-115

Rhopalosyrphus (s.s.) ecuadoriensis Reemer sp. n. Figs 332-336, 352

Type specimens.

HOLOTYPE. Adult male. ECUADOR. Label 1: "ECUADOR: Orellana Province / Yasuni Research Station, / Trap, Canopy - 27 m / Malaise M7-1, AT934 / 11-18.vii.2008, A. Tishechkin"; label 2: "Voucher code M. Reemer / 294 / DNA voucher labcode MZH:Y1089". Coll. RMNH)preliminary deposition, to be transferred to relevant Ecuadorian collection later’.

Diagnosis.

In the key of Weems et al. (2003) this species keys to Rhopalosyrphus australis Thompson, 2003 because tergite 3 is short: a little more than half as long as tergite 2. However, in Rhopalosyrphus australis tergite 3 is about 1/3 as long as tergite 2, which places Rhopalosyrphus ecuadoriensis somewhat intermediate between Rhopalosyrphus australis and the other two known species of Rhopalosyrphus , as far as this character is concerned. Other differences with Rhopalosyrphus australis are (character state in Rhopalosyrphus australis in parentheses): antennal ratio approximately as 5:1:8 (5:1:10), mesoscutum almost entirely black pilose (white pilose), tergite 3 black (yellow).

Description (based on holotype).

Adult male. Body size: 9 mm.

Head. Face occupying slightly less than 1/3 of head width in frontal view; black, except yellow on lateral 1/4 on dorsal 2/3; golden yellow pilose, most densely at yellow lateral parts. Gena black, yellow pilose. Lateral oral margins produced. Frons black; yellow pilose. Vertex black; yellow pilose, except black pilose posteriad of ocelli. Occiput black; yellow pilose. Eye bare; with narrow, horizontal area frontally at level of antenna with enlarged ommatidia. Antennal fossa about 1.5 times as wide as high. Antenna black; antennal ratio approximately as 5:1:8; longer than distance between antennal fossa and anterior oral margin.

Thorax. Black with faint metallic hues. Mesoscutum black pilose, except narrowly white pilose along anterior margin and with small patches of white pile at notopleuron. Postpronotum and postalar callus white pilose. Scutellum semicircular; black pilose dorsally, white pilose along margins; with small apical calcars, with mutual distance about 1/5 of basal width of scutellum. Anepisternum without sulcus; entirely white pilose, except for small patch of black pile posterodorsally. Anepimeron entirely white pilose. Katepisternum white pilose dorsally, bare ventrally. Katepimeron white pilose anteriorly. Katatergum long microtrichose, anatergum short microtrichose. Calypter and halter yellowish white.

Wing: Hyaline, except faintly infuscated around spur on vein R4+5, vein dm-cu, r-m and bm-cu. Microtrichose, except bare on cell bc, basal 1/2 of cell c, basally on cell r1 along vein Rs, entirely on cell br, basal 3/4 of cell bm, anterobasal 1/2 of cell cup and basomedian 1/10 of alula.

Legs: Front and mid femora blackish brown, except narrowly yellow at apex; white pilose, except for sparse long, black pile posterodorsally. Front and mid tibiae pale yellow basally, dark yellow apically; white pilose, except for sparse black pile postero-apically. Front and mid tarsi yellow; black pilose dorsally, yellow pilose ventrally. Hind femur black; white pilose anteriorly and dorsally, black pilose posteriorly and with dense, bristly to spiny black pile ventrally. Hind tibia pale yellow on basal 3/5; yellow pilose, except black pilose posteriorly at apical 1/4. Hind tarsus brown; black pilose dorsally, yellow pilose ventrally. Coxae and trochanters brown to blackish; white pilose.

Abdomen. Constricted, about as wide as thorax, with narrowest point just before posterior margin of tergite 2. Tergites black with bronze hues, except tergite 2 yellow along posterior margin. Tergite 1 white pilose, except white pilose on median 1/4. Tergite 2 white pilose, except black pilose dorsomedially on apical 1/2. Tergite 3 white pilose, except for dorsomedian triangle of black pile over entire length, which is widest at posterior margin; white pile posterolaterally thicker and more conspicuous, thus forming a medially interrupted fascia at posterior margin. Tergite 4 black pilose, except white pilose along lateral margins and with fascia of golden yellow pile on posterior 1/3, which is partly interrupted by black pile anteromedially. Sternite 1 dark brown; bare. Sternite 2 brown on anterior 2/3, yellow on posterior 1/3; white pilose. Sternite 3 yellow anteriorly and along posterior margin, brown medially; white pilose. Sternite 4 brown; black pilose, except white pilose along posterior margin. Male genitalia as in Fig. 352.

Female. Unknown.

Etymology.

The specific epithet (noun in the genitive case) refers to the country where the type has been collected.