Plethysmochaeta lawrencei, R. H. L. Disney, 2010

R. H. L. Disney, 2010, Three new species of scuttle fly (Diptera: Phoridae) from Indonesia, Zootaxa 2357, pp. 63-67 : 63-64

Plethysmochaeta lawrencei sp. nov.

( Figs 1–3 )

In the key to species (Disney, 1995) this will run to couplet 10, where it is distinguished from the other two species by the details of the hypopygium, especially by the process from the rear of the left side of the epandrium and the left lobe of the hypandrium.

Male. Frons brown, wider than long, with numerous hairs and dense but fine microtrichia. With a single pair of strong supra-antennal bristles, the antials and anterolaterals about equally spaced in a more-or-less straight transverse row, and likewise with the mediolaterals and pre-ocellar bristles. With 1–4 bristles on cheek and a single longer bristles on jowl. The subglobose postpedicel brown, but not dark, and lacking subcutaneous pit sensilla. The straw yellow palps only about 0.4x as wide as a postpedicel, distinctly tapered and slightly upcurved towards their tips. Each with 4 longer bristles at and near tip, two smaller ones further back along with at least a dozen hairs. Labrum pale yellow at most 0.75x as wide as a postpedicel. Labella pale, with conspicuous hairs above and below but no small spinules or teeth. Thorax brown and with numerous hairs on propleuron and mesopleuron. Each side of scutum with a humeral bristle, 4 notopleurals, a pre-alar, a postalar and a prescutellar dorsocentral bristle. Scutellum with 4 nearly equal bristles. Abdominal tergites brown with numerous short hairs and longer, more bristle-like, hairs at rear of T6. Venter yellowish grey with numerous hairs on segments 3–5. Hypopygium (which is damaged in the specimen) is light brown to dusky straw yellow in parts. The process at the rear of the left side as Figs 1 . Left lobe of hypandrium as Fig. 2 . Right side of hypopygium as Fig. 3 , with the anal tube mainly brown but the right lobe of the hypandrium almost colourless. Legs with hind femora and tibiae and mid coxae brown and the rest mainly dusky straw yellow. Front tarsus with a posterodorsal hair palisade on segments 1–3. Front tibia with a small dorsal bristle in basal third and a row of 9 spinules beyond it. Mid tibia with the normal pair of bristles in the basal third. Hind femur with hairs below basal half fine but slightly longer than those of anteroventral row in outer half. Hind tibia with an anterodorsal bristle just before mid point and a small one just before tip. Wing 1.3–1.4 mm long. Costal index 0.42–0.43. Costal ratios 1.68: 1. Costal cilia (of section 2) 0.06–0.07 mm long. Sc not reaching vein 1. A small hair at base of vein 3. A single axillary bristle that is clearly longer than costal cilia. Vein 3 thicker than costa. Thick veins brown. Veins 4–6 grey and 7 very pale. Membrane lightly tinged grey. Haltere knob brown.

Material. Holotype male, Indonesia, Sulawesi Utara, Dumoga Bone National Park, Toraut Forest, Malaise trap, 2 March 1985, R. H. L. Disney (University of Cambridge Museum of Zoology, 16–26).

Poloniphora Disney & Durska, 1998

Two Palaearctic species are covered by Disney & Durska (1998) and Disney & Michailovskaya (2002). The species below is the first report of this genus in the Oriental Region. In the key to world genera (Disney, 1994) the males of this subsequently described genus will run to couplet 193, lead 2 to Woodiphora (part). However the latter has only two notopleural bristles plus a notopleural cleft in front of these, whereas Poloniphora has three notopleural bristles and no cleft. The females of this genus will run to couplet 266, where the single axillary bristle on the wing means that neither lead applies.

Figures

FIGURES 1 – 3. Plethysmochaeta lawrencei male, details of hypopygium: (1) process from rear of left side of epandrium; (2) left lobe of hyppandrium; (3) right face of hypopygium. Scale bar = 0.1 mm.