Howickia bicolor Marshall

Marshall, S. A., Luk, S. P. L. & Dong, H., 2014, A revision of the New Zealand species of Howickia Richards, Zootaxa 3887 (1), pp. 1-36 : 9-10

Howickia bicolor Marshall sp. nov.

( Figs. 1 , 19–22 )

Description. Colour: Head, most of the thorax and terminalia yellow; abdominal tergites 1–5, katatergite dark Head: Orbital bristles in a single large pair, subequal to outer vertical, smaller than ocellar and inner vertical bristles. Ocelli small but distinct. Eye 3.0X genal height. Anterior genal bristle strong. Arista with very short hairs, hairs no longer than width of first aristomere.

Thorax: Scutellum with basal marginal bristles slightly longer than apical pair. Wing and halter entirely absent.

Male abdomen: Sternite 5 narrow, dark except for a weakly spinulose posteromedial patch. Synsternite 6+7, sternite 8 and epandrial complex pale orange in contrast with preabdomen. Cercus divided into two parts, upper/ inner part flat and tapered medially to form an incomplete subanal plate, lower/outer part larger, bulging, rounded, and setose. Surstylus broadly U-shaped, posterior lobe narrower and longer than anterior lobe, without spurs or bristles. Hypandrium broadly but asymmetrically fused with anteroventral corners of epandrium, fused area of right side twice as wide as fused area on left. Ventral lobe of hypandrium very prominent, with median anterior part finely serrate on anterior surface. Posterodorsal apodeme of hypandrium strongly developed, reaching anterior surface of distiphallus near base. Distiphallus narrow, tubular. Postgonites narrow, tapered to tip. Basiphallus frame-like, projecting posteriorly at right angle to distiphallus base.

Female abdomen: Ovipositor (segment 6 and posterior) very small and lightly sclerotized, normally retracted into preabdomen, apex compact and difficult to interpret in dissected specimens. Tergite 8 divided into 3 parts, dorsal part bare and shining, lateral parts setose and setulose along posterior margin. Epiproct with two small bristles, posteromedially pale, dark posterolaterally. Cercus very short, as wide as long, setose. Sternite 8 simple, microtrichose, with a few small setae along posterior margin. Hypoproct U-shaped, with arms extending into abdomen as part of a bare plate, microtrichose only at posterior extreme. Spermathecae spherical, ringed with weak transverse striae, paired spermathecae with duct section from junction to bulb as long as bulb.

Type material. Holotype (pointed male, NZAC) and 7 pointed paratypes (5 males, 2 females, NZAC): New Zealand, North Island, Coppermine Island, Hen and Chicken Islands, 24–31.Oct.1968, litter, J.C. Watt leg.

Other paratypes: New Zealand, North Island, Lady Alice Island, Hen and Chicken Islands, 18.Oct.1971, litter, R.H. May (1 female in alcohol, NZAC); Chickens Islands, Whatupuke Island, 28.Oct.1968 (2 males, NZAC).

Comments. The distinctive and contrasting colours, with the head, most of the thorax and male postabdomen yellow in contrast with the dark preabdomen and katatergite, render this species unmistakable. Howickia bicolor is known only from the Hen and Chicken Islands, east of the North Auckland Peninsula, 40 kilometers southeast of Whangarei. Only one female was dissected, and the apical abdominal sclerites are minute, pale and compact, with individual sclerites difficult to discern.

Figures

FIGURES 1 – 8. Howickia trilineata group, plate 1. Howickia bicolor Marshall, sp. n.: 1, habitus. Howickia oliveri Marshall, sp. n.: 2, habitus; 3, head; 4, right wing. Howickia mercurialis Marshall, sp. n.: 5, habitus; 6, left wing. Howickia omamari Marshall, sp. n.: 7, head; 8, habitus.

FIGURES 19 – 22. Howickia bicolor Marshall, sp. n.: 19, epandrium, posterior; 20, epandrium, left lateral; 21, male sternite 5; 22, aedeagus and associated structures.