Howickia auricoma, Kuwahara & Marshall, 2022

Kuwahara, Gregory K. & Marshall, Stephen A., 2022, A revision of the Australian species of Howickia Richards (Diptera: Sphaeroceridae: Limosininae), Zootaxa 5192 (1), pp. 1-152 : 103-106

Howickia auricoma sp. nov.

( Figs. 29.1–29.8 )

Description. Body length: Males 2.0– 3.1 mm, females 2.5–3.3 mm.

Head: Dark reddish-brown, darkened at level of ocelli and behind, dull and microtrichose except frontal vitta (shiny despite some microtrichia); gena reddish; antenna brown. Frontal width 1.5x interfrontal height, frontal vitta broad. Three pairs of fine, moderate interfrontal bristles; 2 lateroclinate orbital bristles, anterior bristle 0.7x length of posterior bristle. Gena with 3–4 strong but fine upcurved setae, finely striate, shiny, lower half microtrichose; vibrissal angle with 1 subvibrissal seta. Face with a broad, flattened, microtrichose triangle along ventral margin; palpus clavate with 2 large apical setae. Eye height 2.9x genal height.

Thorax: Black; scutum shiny despite fine brown microtrichia, posterior edge reddish. One pair of dorsocentral bristles; 7–8 rows of long, fine acrostichal setulae. Prosternum broad, anteriorly truncate. Scutellum shiny but heavily microtrichose, black, rectangular, its length 0.3x its width; 4 scutellar bristles long, basal pair 1.1x length of apical pair.

Legs: Dark brown, tibiae proximally lighter; tarsi yellow-brown. Male mid tibia with a stout apicoventral bristle. Basal half of mid tibia with 2 dorsal bristles (1 anterodorsal and 1 posterodorsal), distal half with 2 dorsal bristles (1 anterodorsal and 1 posterodorsal).

Wing/halter: Halter absent.

Male abdomen: Black, heavily sclerotized, shiny, postabdomen slightly lighter. T2–5 and S2–4 uniformly longsetose along entire surface with large posterolateral setae. S5 broad but short (width 4.5x length), asymmetrical (right side 1.5x longer than left), uniformly long-setose with a posteromedial desclerotized lobe bearing 8 large anterior setae, 6 short medial setae and a posterior row of 12 short, flat teeth. Epandrium large, flattened, angled posteroventrally and uniformly long-setose; cercus slightly protruding, rounded with a very large, curved dorsal thorn-like seta, 1 long medial seta and a dense patch of fine golden setae. Hypandrium medially gently sinuate; ventral lobe elongate, largely reduced medially into a whip-like sclerite with a thin central membrane; posterodorsal lobe sinuate, broadly attached anteriorly and tapered posteriorly. Surstylus bilobed: anterior lobe elongate with a dorsal hook and a few short ventral setae; posterior lobe elongate, projecting anteroventrally with a large blade-like inner seta, numerous long apical setae, and many short setae along posterior edge. Postgonite almost rhomboid with a small apicolateral tab. Phallapodeme curved, constricted at anterior third with large dorsal fin along entire length; basiphallus short, capitate. Distiphallus rather simple, largely desclerotized with basal half tubular and apical half leaf-shaped and angled ventrally.

Female abdomen: Black, heavily sclerotized, shiny. T2–5 and S2–5 wide, uniformly long-setose along entire surface with large posterolateral setae; pleural membrane bare. Preabdomen subequal in length to head + thorax. Postabdomen short, stout, 1.9x length of T5. T6 and T7 reduced to L-shaped plates, each bearing 3 apical setae. Epiproct rectangular and bearing a dorsomedial pair of setae. Cercus elongate, subtriangular with 3 long sinuate setae (1 apical, 1 lateral and 1 dorsal) and several smaller setulae. S6 and S7 reduced to short, broad plates bearing a posterior row of 8 setae. S8 a broad microtrichose plate with a patch of 4 setae. Hypoproct rectangular, microtrichose with a posterior row of 6 setae. Spermathecae elongate, cylindrical, and strongly grooved with a shallow apical invagination; stem short (0.3x length of spermatheca) and cylindrical.

Material examined. Holotype: AUSTRALIA: Victoria: Mount Donna Buang , 1200 m, 28.iv.–7.v.1978, S.& J. Peck (♂, ANIC).

Paratypes: same data as holotype (24 ♂, 24 ♀, ANIC, DEBU) .

Etymology. This name is in reference to the dense patch of golden setae on the male cercus (Latin ‘auricomus’: with golden hair, golden-haired).

Comments. Howickia auricoma is externally similar to H. holti , but differs in having a redder head, only one orbital seta (two present in H. holti ) and lacking an outer vertical setae (small but present in H. holti ).

Figures

FIGURES 29.1–29.5. Howickia auricoma sp. nov. 29.1, male habitus, lateral; 29.2, male head, anterolateral; 29.3, male S5–8, ventral; 29.4, male terminalia, lateral; 29.4a, left surstylus, posterior; 29.5, aedeagus and associated structures, lateral. Scale bars indicate 0.5 mm.