Mycomya pongo, Väisänen, Rauno, 2014

Väisänen, Rauno, 2014, New Mycomya species from South-East Asia (Diptera, Mycetophilidae), Zootaxa 3815 (4), pp. 526-540 : 533-536

Mycomya pongo sp. n.

Figs. 6 A–F

Material studied. Holotype. ♂. MALAYSIA; Borneo, Sabah, Mt Kinabalu, 1300–2000 m, 6.xi. 1975, H. Shima (KUC). Other material. Same locality, 1300 m, 9–11.XI. 1975, H. Shima, 1 ♀ (KUC).

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Description. ♂. Head. Palp brownish, other mouthparts and face yellow, posterior parts of head brownish to brown. Antenna brownish, scape yellowish. 1st flagellomere about 5x its width, 2nd flagellomere 3x its width. Thorax. Pronotum yellow, with 3 long setae. Scutum yellow with 3 brownish partially fused longitudinal stripes. Anepisternum and preepisternum yellow. Scutellum brownish, with 4 long setae. Laterotergite brownish. Mediotergite brownish, bare. Wing. Length 4.4 mm. Wing hyaline. Sc ending in R1 distinctly proximad of middle of small cell, Sc1 missing. Apical part of Sc bearing small setae (exact number of setae not known due to poor wing condition). Small cell slightly longer than its width. Cu fork distal to M fork. M ratios: 1.00, 1.44. Cu ratios: 1.00, 1.61. Small setae: M petiole: 0; M1: 0–1; M2: 0; Cu petiole: 0; Cu1: 0; Cu2: 0. Halter pale yellowish, apex light brownish. Legs. Coxae and femora yellow, tibiae and tarsi brownish to brown. Coxa 2 without spur. Leg ratios: bt1:t1 =? (structure missing), bt2:t2 = 0.73, bt3:t3 = 0.60. Abdomen. Tergites brownish, sternites yellowish to brownish. Hypopygium. Figs. 6 A–F, yellowish. Tergal part with two pairs of combs. Outer combs widely separated from each other, both with 4–5 spines, inner combs both with 7–8 spines ( Fig. 6 A). On both sides of tergal part 4 setae between outer comb and base of tergal lateral appendage. Tergal lateral appendage very long, slender, about 8x as long as its width and curved, with wide, bare, basal and middle part, and group of curved, flattened, apical setae ( Fig. 6 D). Gonostylus relatively long, about 6x as long as its width, with two apicalsubapical teeth, and a narrow membranous lateral lobe about as long as main branch of gonostylus ( Fig. 6 E). Sternal submedian filament missing ( Fig. 6 B). Aedeagus with two lobes bearing subapical setae ( Figs. 6 B, 6F). Female. Wing length 3.7 mm. Thorax yellowish. Abdomen light brownish. Leg ratios: bt1:t1 = 0.83, bt2:t2 =? (structure missing), bt3:t3 = 0.59. Terminalia yellowish. Hypogynal valve tapering apically, with several setae. Apical segment of cercus oval.

Discussion. Mycomya pongo belongs to the subgenus Mycomyopsis (as discussed for M. apoensis above). It differs from the other species of the subgenus Mycomyopsis in the shape and reduced setosity of its very long and slender tergal lateral appendage ( Fig. 6 D). It slightly resembles that found in the Nepalese M. sanar Väisänen (2013c: figs. 14A–F) , which is also lacking the sternal submedian filament and the spur of the gonostylus like M. pongo . However, M. sanar has a group of setae at the base of the tergal lateral appendage, in addition to the groups of setae in front of the tergal combs between the outer tergal comb and the base of the tergal lateral appendage ( Väisänen 2013a: figs. 14A, 14D). Its gonostylus ( Väisänen 2013c: fig. 14E) is short and wide (about 4x as long as its width), with a strong spine slightly beyond the middle part of the gonostylus, three subapical teeth, and a short membranous lateral lobe (about 1/3 of the length of the gonostylus), whereas M. pongo has a longer gonostylus (about 8x as long as its width) without a middle spine and with a membranous lateral lobe about as long as the main branch of the gonostylus ( Fig. 6 E). The structure and setosity of the apical part of the tergal lateral appendage ( Fig. 6 D) is quite unique in M. pongo , somewhat resembling that of the New Caledonian M. minuscula Matile (1991: figs. 2 and 4) , which has several setae in the middle part of its tergal lateral appendage. Mycomya pongo specimens were collected at elevations of 1300–2000 m in November. Mt. Kinabalu is the highest mountain (4095 m) between the Himalayas and New Guinea. It is a granite intrusion with a wide range of habitats and many endemic species. It has been a national park since 1964 and a UNESCO World Heritage Site since 2000.

Etymology. The species name is a noun in apposition and refers to the Bornean orangutan, Pongo pygmaeus (Linnaeus).

Figures

FIGURE 6. Mycomya pongo sp. n., male hypopygium. A – C tergal, sternal and lateral views, D apex of tergal lateral appendage, twice enlarged, E gonostylus, twice enlarged, F apex of aedeagus, lateral view, twice enlarged. Scale 0.2 mm.