Oligoxenomyia radicis Felt

Kolesik, Peter & Gagné, Raymond J., 2020, A review of the gall midges (Diptera: Cecidomyiidae) of Indonesia: taxonomy, biology and adult key to genera, Zootaxa 4847 (1), pp. 1-82 : 48

Oligoxenomyia radicis Felt

[ Figs 25 a–n]

Oligoxenomyia radicis Felt, 1927b: 386 .

Material examined. Syntypes: 6 males, 10 females, 2 pupae reared from aerial root galls on Freycinetia sumatrana Hemsl. (as F. valida Ridl. ) ( Pandanaceae ), gall No 45 in DvLR & DvL (1926) collected at Bolang, near Bogor , Java, iii-1924. Felt #a3391). Felt’s types are mounted on 4 slides, all uncleared, whole specimens, adults in lateral position, pupae in dorso-ventral. All characters preserved in at least one specimen .

Description. Adult. Palpal segments 3, segments progressively longer [ Figs 25g, h ]. Tarsal claws bent at right angle close to basal third, tip pointed, bowed, empodia reaching bend of claw [ Fig. 25f ].

Male. Wing length 2.7 mm (2.5–2.9), width 1.0 mm (0.9–1.2) [ Fig. 25a ]. Flagellomeres [ Fig. 25b ]. Terminalia [ Figs 25 c–e].

Female. Wing length 3.5 mm (3.3–3.7), width 1.4 mm (1.3–1.4). Flagellomeres slightly constricted at midlength [ Fig. 25i ]. Terminalia [ Figs 25j, k ].

Pupa. Antennal horns long, narrow, broadly rounded in ventral view [ Fig. 25l ]. Prothoracic spiracle long, tapered, bowed at distal third, with small spikes distally, trachea ending below distal end [ Fig. 25m ]; spiracles on abdominal segments sessile. Abdominal segments dorsally with dense field of large, simple spikes.

Larva unknown.

Biology. This species causes an aerial root gall on Freycinetia sumatrana Hemsl. (Pandanaceae) described by DvLR & DvL (1926, gall No 45, Fig 24 . [ Fig. 25n ]). Irregular swellings are partly coalescent and attached to the root with broad bases. The surface is covered with numerous short, brown hair-like scales. The interior contains many long and tubular larval chambers, crossing the longitudinal axis of the root.

Geographical distribution. This species is known from Java: Mt Ciampea, near Bogor , alt. 200 m, 1920; Mt Burangrang , alt. 1100 m, vii-1921; Bolang, near Bogor, alt. 950 m, iii-1924 (DvLR & DvL 1926) .

Figures

FIGURES 24a–j. Megommata leefmansi: a, male head; b, tarsal claw of foreleg; c, tarsal claw of mid or hind leg; d, palpus; e, wing; f, female terminalia (lateral); g, 3rd male flagellomere; h, gonostylus (dorsal); i, male terminalia (dorsal); j, 1st and 2nd female flagellomeres. Figs a, d–j from Harris (1968), Figs b, c from Nijveldt (1954).

FIGURES 25a–n. Oligoxenomyia radicis: a, wing; b–g, male: b, 3rd flagellomere; c, terminalia (mesolateral); d, gonostylus (ventral); e, gonostylus (dorsal); f, claw and empodium; g, palpus; h–k, female: h, palpus; i, 3rd flagellomere; j, ovipositor (lateral); k, cercus and hypoproct (lateral); l–m, pupa: l, antennal horns and cervical papillae (ventral); m, prothoracic spiracle; n, aerial root gall on Freycinetia imbricate (Fig. 24 of DvLR & DvL (1926)).