Matsumyia bimaculata, Huo, Keke & Ren, Guodong, 2006

Huo, Keke & Ren, Guodong, 2006, A key to known species of Mastumyia Shiraki (Diptera, Syrphidae) from China, with descriptions of two new species, Zootaxa 1374, pp. 61-68 : 63-64

Matsumyia bimaculata sp. nov.

( Figs. 1–3 )

Diagnosis. Abdomen broadly oval. The 2nd abdominal tergite marked with triangular orange spots laterally, with inner ends separated broadly. The 3rd tergite marked with small orange spots at base laterally, with a pair of narrow, elongate, transverse white pruinosity bands situated nearly in the middle laterally, broadly separating medially. The 4th tergite decorated with a pair of short lateral white pruinosity bands in the middle laterally.

Adult. ɗ (Ψ unknown). Body length 15 mm, wing length 12 mm.

Head. Black in ground color; broader than thorax. Eyes bared, shortly confluent on frons. Vertex narrow, elongate, covered with black hairs. Ocellar triangle situated at the middle of vertex. Occiput clothed with yellowish white hairs and tomentum. Frons small with longitudinal furrow medially, protruded conspicuously, with sparse black hairs and whitish yellow tomentum laterally but bare anteriorly. Lunule reddish yellow. Face deeply concave below frontal prominence in profile, almost straight below facial tubercle, with facial tubercle rounded. Face sparsely yellow pilosed along eye margins and below eyes, with whitish yellow tomentum most part, but shiny black laterally. Eye orbits extended from below eyes up to the level of upper margin of facial tubercle, with a small spot of whitish yellow tomentum just below eyes. Antennae tawny, with basal 2 segments pilosed dorsally and ventrally, first flagellomere shorter than basal 2 segments together, broader than long. Arista bare, long, dull brown but yellowish brown at basal 1/3.

Thorax. Scutum densely covered with grey yellow pruinosity concealing the ground color, with a pair of longitudinal grey yellow pollen stripes in the middle anteriorly, extending over transverse suture. Dorsum of mesothorax clothed with long whitish yellow hairs, which longer on postalar callus. Scutellum decorated with whitish yellow pruinosity and dense long hairs. Mesopleuron black with proepisternum, anepisternum posteriorily, katepisternum anteriorly and posteriorly, anepimeron dense yellow pollinose and long pilose. Metasternum covered with long yellow hairs and pruinosity. Fore legs with coxae and trochanters black, femora black with yellow brown apex, conspicuously thickened, covered with whitish yellow hairs which longer at base posteriorly, tibiae and tarsi dull brown with yellow brown hairs, tibiae darkened at apical half, tarsi with segments 3–5 black brown dorsally. Middle legs similar to fore legs, but femora with long hairs posteriorly, tarsi with segment 5 black brown. Hind legs with coxae and trochanters black, coxae with whitish yellow pruinosity and hairs, trochanters shiny, with short, sparse hairs, femora distinctly thickened at the middle, black, with brownish yellow hairs except long whitish yellow hairs anterodorsally, black spines ventrally and more denser nearly at apical part, a row of long yellow hairs separating broadly and evenly on the ventral bilaterally, tibiae compressed laterally, bent slightly with a obtuse tooth at apical margin inside, tibiae and tarsi black brown. Wings hyaline, with cell R1 open, vein r4+5 straight, cell R5 distinctly petiolar, upper and lower cross-vein parallel with margin of wing, vein r-m oblique, situated behind the middle of cell M2, stigma vein present.

Abdomen. Black, broadly oval, covered with short, adpressed black hairs for most part. The 1st tergite densely covered with whitish yellow pruinosity and hairs. The 2nd tergite with yellow hairs basally and laterally, marked with triangular orange spots laterally, of which the inner ends separated broadly. The 3rd tergite marked with small orange spots at base laterally and a pair of narrow, elongate, transverse white pruinosity bands situating nearly at the middle laterally, with inner ends broadly separated. The 4th tergite decorated with a pair of short bands of white pollen at the middle laterally. The 5th tergite covered with grey pruinosity basally. Venter black, covered with grey pruinosity and spots, basal 2 segments with sparse, long, yellow hairs.

Type material. Holotype ɗ, deposited in BKLSUT. China, Sichuan Province, Muyang, Nanjiang County, 800m, 2005. viii. 1, Keke Huo.

Etymology. The specific epithet refers to two pairs of yellow spots and white pollen bands on abdomen.

Distribution. China (Sichuan Province).

Remarks. The new species can be separated from other species of the genus by abdomen with two pairs of yellow spots and white pollen bands.

Figures

FIGURES 1 – 3. Matsumyia bimaculata sp. nov. ♂. 1, lateral view of head; 2, antenna; 3, dorsal view of abdomen.