Howickia regalis (Richards) 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 : 135-138

Howickia regalis (Richards) comb. nov.

( Figs. 42.1–42.12 )

Bentrovata regalis Richards, 1973: 394 ; Marshall, 1989: 602; Roháček et al., 2001: 124; Papp, 2021: 114 .

Bentrovata minor Papp, 2021: 110 . syn. nov.

Bentrovata nigrithorax Papp, 2021: 112 . syn. nov.

Description. Body length: Males 1.5–2.9 mm, females 1.7–2.8 mm.

Head: Golden yellow to orange-brown, area surrounding ocellar triangle and behind dark brown, sometimes darkened centrally; frontal vitta, interfrontal plates and orbital plates with pale yellow, microtomentose stripes (5 total), stripes on orbital plates extending inwards to above interfrontal plates; gena yellow; antenna yellow. Frontal width 1.5x interfrontal height, frontal vitta narrow. Two pairs of large interfrontal bristles preceded by a much smaller pair (0.3x length of posterior pairs); 1 lateroclinate orbital bristle. Gena with strong but fine upcurved bristle and 2 smaller setae, finely rugose and microtrichose; vibrissal angle with 1 smaller seta. Face shiny with broad flattened triangle along ventral margin; palpus clavate with 2 large apical setae. Eye height 3.5x genal height.

Thorax: Black to reddish-brown or yellow (dark and light morphs); scutum dull, lateral edges reddish; katatergite dark brown in light morph. One pair of dorsocentral bristles; 7–8 rows of fine acrostichal setulae. Prosternum narrow, linear, posteriorly expanded. Scutellum heavily microtrichose, reddish, semicircular, its length 0.3x its width; 4 scutellar bristles long, basal pair 1.3x length of apical pair.

Legs: Brown or yellow, tibiae proximally and distally lighter in darker morphs; tarsi brown or yellow. Male mid tibia with a large 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 to reddish-brown, heavily sclerotized, shiny, postabdomen slightly reddish. T2–5 and S2–4 uniformly long-setose along entire surface. S5 broad but short (width 4.0x length), asymmetrical (right side longer than left), sparsely long-setose, broadly posteromedially emarginate, posteromedially desclerotized section with 14 stout medial setae and paired, curved rows of 10 short, flat teeth. Epandrium small, broad, sparsely longsetose; cercus large, subtriangular with 1 long sinuate seta and several smaller setae. Hypandrium medially sinuate; ventral lobe narrow, curved and projecting from main part at an angle of 70˚; posterodorsal lobe slightly curved, apically rounded, extending from posterior edge of main part. Surstylus small, bean-shaped with many small lateral setulae and a short, stout posteroventral thorn-like seta. Postgonite narrow, elongate, sinuate, proximally with a pair of anterior setulae, apical half with serrate posteroventral edge, apex a rounded knob. Phallapodeme slightly sinuate, constricted at anterior tenth, apically expanded; basiphallus bent about half length, resembling a horse head, base narrow and rounded, apex broad and truncate. Distiphallus simple, sinuate, tubular, largely desclerotized (especially apically); apex pointed.

Female abdomen: Black to reddish-brown, heavily sclerotized, shiny. T2–5 and S2–5 uniformly long-setose along entire surface; pleural membrane with small setal patch. Preabdomen subequal in length to head + thorax. Postabdomen short, stout, 1.8x length of T5. T6 and T7 relatively well-developed, present as broad, U-shaped plates bearing a posterior row of 8 setae. Epiproct small, broad and dorsomedially bearing a pair of widelyseparated setae. Cercus short and rounded with 2 long sinuate setae (1 apical and 1 dorsal) and several smaller setulae. S6 and S7 broad, well-developed, microtrichose plates bearing a posterior row of 12 setae. S8 a broad, microtrichose, hemispherical plate with a small anteromedial emargination and several posterior setae. Hypoproct broad, anteromedially emarginate, centrally desclerotized and posteriorly microtrichose with a row of stout setulae. Spermathecae stout, spherical and entirely lightly grooved with a slightly basal constriction; stem short (0.8–0.9x length of spermatheca) and tapered.

Type material. Holotype: AUSTRALIA: Western Australia: Perth, King’s Park , in alcohol ex leaf litter, ix.1957, G. Bornemissza ( ANIC).

Paratypes: AUSTRALIA: Western Australia: Perth, King’s Park , 9.vi.1952 (1 ♀, ANIC) ; Perth, King’s Park , 1952–57 (1 ♂, ANIC) , same data as holotype (2 ♂, 1 ♀, ANIC) .

Material examined. AUSTRALIA: Western Australia: Albany, Two People’s Bay Nature Reserve , heath, dung cup traps, 9–14.vi.1980, S. & J. Peck (3 ♂, 1 ♀, DEBU) ; Albany, Two People’s Bay Nature Reserve , heath, mini carrion trap, 9–14.vi.1980, S. & J. Peck (2 ♂, 6 ♀, DEBU) ; Augusta, Boranup State Forest , 25 km N Augusta, 34˚09’52”S 115˚04’34”E, karri forest, pans, 20–23.xi.1980, S.A. Marshall (1 ♂, 1 ♀, DEBU) ; Augusta, Boranup State Forest , karri forest, dung cup traps, 19–22.vii.1980, S. & J. Peck (7 ♂, 16 ♀, DEBU) ; Augusta, Leeuwin– Naturaliste National Park, The Spring Trail , forest, dung traps, 19–22.vii.1980, S. & J. Peck (6 ♂, 10 ♀, DEBU) ; Augusta, Port Leeuwin , pans in heath, 20–22.xi.2003, S.A. Marshall (1 ♀, DEBU) ; Coronation Road , 35 km SW Manjimup, jarrah forest, dung traps, 14–17.vii.1980, S. & J. Peck (9 ♂, 12 ♀, DEBU) ; Fernhook Falls, 30 km N Walpole, Deep River shoreline, dung pans, 26–27.xi.2003, S.A. Marshall (8 ♂, 11 ♀, DEBU) ; Forth River, 45 km SE Northcliffe, Chesapeake Road , forest to heath, dung cups, 11–16.vii.1980, S. & J. Peck (1 ♂, DEBU) ; Margaret River, Rosa Brook Road , forest, dung cup traps, 22–26.vii.1980, S. & J. Peck (1 ♂, 1 ♀, DEBU) ; Mount Frankland , 30 km N Walpole, pans, 26.xi.2003, S.A. Marshall (1 ♀, DEBU) ; Nannup, Barrabup Pool , marri forest, dung cup traps, 23–26.vii.1980, S. & J. Peck (2 ♂, DEBU) ; near Quininup , 29 km SSE Manjimup, karri forest, dung traps, 13–16.vii.1980, S. & J. Peck (9 ♂, 10 ♀, DEBU) ; Northcliffe Park, 1 km E, karri forest, dung traps, 13–16.vii.1980, S. & J. Peck (4 ♂, 6 ♀, DEBU) ; Pemberton, Gloucester Tree , karri forest, dung cup traps, 5–9.vii.1980, S. & J. Peck (3 ♂, DEBU) ; Pemberton, The Cascades , jarrah forest, dung cup traps, 7–13.vii.1980, S. & J. Peck (1 ♂, DEBU) ; Porongurup National Park, Bolganup Creek , karri, dung trap, 8–16.vi.1980, S. & J. Peck (1 ♀, DEBU) ; Sterling Range National Park, Gold Holes , heath, carrion traps, 8–15.vi.1980, S. & J. Peck (6 ♂, 7 ♀, DEBU) ; Sterling Range National Park, Toolbrunup Trail , dung cup traps, 10.vi.1980, S. & J. Peck (7 ♂, 3 ♀, DEBU) ; Sterling Range National Park, Toolbrunup Trail , mini carrion traps, 10.vi.1980, S. & J. Peck (9 ♂, 1 ♀, DEBU) ; Sues Bridge , 50 km SW Nannup, marri forest, dung cup traps, 24–26.vii.1980, S. & J. Peck (2 ♂, 3 ♀, DEBU) ; 6.5 km W of Walpole , karri forest, leafmould, 70m, 22.x.1969, R.W. Taylor (1 ♂, ANIC) ; Walpole National Park, Peaceful Bay , coast sand heath, pan trap, 17.vi–11.vii.1980, S. & J. Peck (1 ♀, DEBU) ; Walpole National Park , tingle tree forest, “aini” carrion traps, 19.vi–4.vii.1980, S. & J. Peck (1 ♂, DEBU) ; Walpole National Park , tingle tree forest, dung cup traps, 21.vi.1980, S. & J. Peck (31 ♂, 28 ♀, DEBU) ; Walpole National Park , tingle tree forest, dung cup traps, 4.vii.1980, S. & J. Peck (23 ♂, 62 ♀, DEBU) ; Walpole National Park , tingle tree, forest dung cup traps, 18.vi–29.vii.1980, S. & J. Peck (43 ♂, 57 ♀, DEBU) ; Walpole , 15 km E, tingle tree forest, dung pans in leaf litter, 28–30.xi.2003, S.A. Marshall (1 ♀, DEBU) ; Windy Harbour , 27 km S Northcliffe, coast heath, dung cup traps, 8–12.vii.1980, S. & J. Peck (2 ♂, 1 ♀, DEBU) ; Wrenwood Cottages , 10 km N Augusta, 34˚15’S 115˚01’E, paperbark grove, pans, 20–23.xi.2003, S.A. Marshall (1 ♂, 3 ♀, DEBU) .

Comments. The types for Howickia regalis could not be located, but this species is readily distinguished from almost all other wingless species of Howickia by the five microtrichose stripes on the frons. The only other wingless species with similar pigmentation is H. irwini , which has two orbital bristles in contrast to the single orbital bristle of H. regalis . Richards’ (1973) description of external characters matches the yellow thorax morph of the species, though there are two other morphs (one with a yellow head and black thorax and one with a dark brown head and black thorax). Richards’ illustrations of the male surstyli and S5 are not a perfect match to the specimens described above, as he depicts the surstylus as more triangular and S5 without posteromedial teeth. However, his illustrations are often oversimplified and lack fine details. Howickia regalis is known only from WA.

The descriptions of Papp’s (2021) “ Bentrovata minor ” Papp, 2021 and “ B. nigrithorax ” Papp, 2021 both match up exactly to two of the darker colour morphs of H. regalis , the morph with a dark head and thorax and the morph with a yellow head and dark thorax, respectively. The illustrations of the male genitalia of “ B. minor ” also match up almost exactly with genitalia of H. regalis . Examining the hundreds of specimens in the University of Guelph Insect Collection revealed slight variation in the posteromedial row of teeth on the male fifth sternite which correspond to the differences between Papp’s (2021) illustrations of “ B. minor ” and H. regalis . No males of “ B. nigrithorax ” were found, but the description of the female and the female genitalia describe those of H. regalis . The distribution of both “ B. minor ” and “ B. nigrithorax ” both overlap the distribution of H. regalis . These two species are therefore treated here as synonyms of Howickia regalis .

The yellow morph of H. regalis is externally similar to H. flavithorax (see above), and both species are known from the same areas of WA. However, the yellow morph of H. regalis can be easily distinguished by its striped, microtrichose frons (entirely smooth in H. flavithorax ), three pairs of stout interfrontal setae (four very fine pairs in H. flavithorax ), the presence of outer vertical setae, and a pure yellow katepimeron.

Bentrovata was described by Richards (1973) and justified as a distinct genus by the differences (size of the interfrontal setae, the shape of the prosternum, and the size of the abdomen) between the type species ( B. regalis ) and “ Aubertinia ” Richards, 1951 (= Phthitia Enderlein, 1938 ) in his 1956 key to flightless genera. However, the type species has the two pairs of dorsal mid tibial bristles, striped frons, male S5 with a posteromedial row of stout, and tooth-like setae found in other species of Howickia , and the tripartite hypandrium which defines Howickia . Bentrovata is therefore treated as a synonym of Howickia . The synonymy of Bentrovata with Howickia creates a homonym of the New Zealand H. regalis Marshall , which is here renamed as H. neoregalis Kuwahara & Marshall nom. nov.

Figures

FIGURES 42.1–42.6. Howickia regalis (Richards). 42.1, light morph male habitus, lateral; 42.2, light morph male head, anterolateral; 42.3, dark morph male habitus, lateral; 42.4, dark morph male head, anterolateral; 42.5, darkest morph male habitus, lateral; 42.6, darkest morph male head, anterolateral. Scale bars indicate 0.5 mm.