Machimus aurulentus Becker, 1925

(Figs 5, 18, 34, 35 & 62)

Machimus aurulentus Becker 1925 Becker (1925: 249) .

Medium size, bright yellow flies, 17 to 20 mm. Easily recognized by the bright yellow setose abdomen. Epandrial lobe wide, obtuse (Fig. 5), apex in posterior view sigmoid. Gonostylus sub apically notched (Fig. 18). Aedeagus truncated with three long slender prongs (Figs.34, 35). Ovipositor of compressed segments 8 and 9, short segment 9, and free cercus (Fig. 62).

Head: Mystax with long white and yellow hair below and black, shorter hair above.

Thorax: Clearly defined dark paramedian stripe of scutum and posthumeral spots. Chaetotaxy with 6 pronotal; 3 notopleural; 3 supraalar; 3 postalar, and 6 dorsocentral bristles. Scutellum gray tomentose with sparse black proclinate hair, margin with 6 black bristles. Pleura gold pollinose with black and yellow hair. Legs: Entirely black with yellow and black hair. Wings: Wide marginal and submarginal cell rippled; entire wing tinged brown. Abdomen: Tergites bright yellow tomentose, appressed yellow hair along posterior margins of dorsal and lateral tergites 1 5. Male sternite 8 with a fringe of long yellow hair. Hypandrium reduced. Epandrial lobe wide, obtuse, apex in posterior view sigmoid. Gonostylus sub apically notched and with a median lateral tubercle (Fig. 18). Aedeagus truncated with three long slender prongs (Figs. 34 35). Ovipositor of compressed segments 8 and 9, short segment 9, and cercus free (Fig. 62).

South Korean distribution. Ch ǒ llabuk ­Do Province. Iksan­Shi. Mirŭksan. 36°01’12”N, 127°01’52”E. Kunsan. Umpa Lake. 35°57’93”N, 126°41’78”E. Ch’ungch’ ǒ ngnam­Do Province. Kŭmsan­Gun. Kŭmsan. Posoksa (no coordinates available). Ky ǒ ngsangnam­Do Province. Macheon. Chirisan Mt. 705m. 35°20’55”N, 127°38’21”E. Samjeong­Li. Macheon. Chirisan Mt. 6– 800m. 35°21’36”N, 127°38’25”E.

Material examined. 1ɗ, 1Ψ: 6/X/2004, Chŏllabuk­Do Province, Iksan­Shi, Mirŭksan; 2Ψ: 30/VIII/1998, Chŏllabuk­Do Province, Kunsan, Umpa Lake; 1ɗ: same data except 6/ IX/1998; 1ɗ, 3Ψ: same data except 8/IX/2004; 1ɗ: same data except 12/IX/1998; 2ɗ, 6Ψ: same data except 1/X/2002; 1ɗ: 10–14/IX/1998, P. Tripotin coll., Ch’ungch’ŏngnam­Do Province, Kŭmsan­Gun, Kŭmsan, Posoksa, Malaise canopée; 1ɗ: same data except 29/IX/ 2002; 1ɗ, 1Ψ: 6/IX/2003, P. Tripotin coll., Kyŏngsangnam­Do Province, Macheon, Chirisan Mt. 705m.; 3ɗ: same data except 27/IX/2003; 2ɗ: same data except 4/X/2003; 4ɗ: 24/VIII/2002, P. Tripotin coll., Kyŏngsangnam­Do Province, Samjeong­Li, Macheon, Chirisan Mt. 6– 800m.; 1ɗ, 1Ψ: same data except 24/VIII/2002, From Malaise Trap; 2ɗ, 1Ψ: same data except 20/X/2002.

Field notes. Machimus aurulentus inhabits perimeter thickets of open fields and burial mound areas surrounded by pine saplings and a deciduous shrub layer where it forages from grass stalks and leaves. The asilid appears in late August to mid October in South Korea. Both species of Machimus are widespread in South Korea and occupy sympatric and allopatric habitats.