Howickia flavithorax Kuwahara & Marshall 2022, comb. nov.
Creators: name: Kuwahara, Gregory K.
name: Marshall, Stephen A.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Sphaeroceridae
Howickia
Howickia flavithorax

description: Howickia flavithorax (Papp) comb. nov.
(Figs. 36.1–36.8)
Bentrovata flavithorax Papp, 2021: 110.
Description. Body length: Males 1.9–2.5 mm, females 1.7–2.5 mm.
Head: Yellow and shiny except strips between orbital plate and interfrontal stripe darker gold and rugose; gena pale yellow; antenna slightly darker. Frontal width 1.6x interfrontal height, frontal vitta broad. 3–4 pairs of very fine interfrontal bristles, medial pairs slightly longer than others; 1 lateroclinate orbital bristle. Gena with strong but fine upcurved bristle and 7–8 smaller setae, finely rugose, shiny, lower half microtrichose; vibrissal angle with 2 smaller setae. Palpus clavate with 1 large apical seta. Eye height 3.0x genal height.
Thorax: Yellow; scutum shiny and often transparent; anepimeron darkened posteroventrally; lower two-thirds of katepimeron dark brown; katatergite dark brown. One pair of dorsocentral bristles; 7–8 rows of long, fine acrostichal setulae. Prosternum broad, anteriorly truncate. Scutellum shiny, orange, rectangular, its length 0.3x its width; 4 scutellar bristles long and all along posterior edge, basal pair 1.2x length of apical pair.
Legs: Yellow, fore tibia brown; tarsi beige. 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, heavily sclerotized, shiny despite microtrichia. T2–5 and S2–4 uniformly long-setose. S5 broad but short (width 5.0x length), asymmetrical (right side 2.0x longer than left), posteromedially desclerotized with dense patch of short stout setae, otherwise sparsely long-setose. Epandrium large, spherical, and uniformly long-setose; cercus enlarged, subquadrate with very dense fine setae. Hypandrium medially slightly sinuate; ventral lobe broad, dark, triangular; posterodorsal lobe elongate. Surstylus bean-shaped, with a thick, posteroventral, anteroventrally-directed thorn-like seta and a lateral patch of fine setae. Postgonite elongate, curved apically, ventral edge serrate with numerous minute setulae. Phallapodeme sinuate; basiphallus short, boot-shaped. Distiphallus divided into two distinct sections: basal half heavily sclerotized with a large saddle-like dorsal sclerite and a flattened ventral sclerite articulating to form a tube; distal half with a V-shaped dorsal sclerite and a long, thin ventral sclerite supporting a membranous apical tube.
Female abdomen: Black, heavily sclerotized, shiny despite microtrichia. T2–5 and S2–5 uniformly long-setose. Preabdomen subequal in length to head + thorax. Postabdomen short, stout, 1.5x length of T5. T6 and T7 relatively well-developed, present as broad plates, each bearing 5–6 apicolateral setae. Epiproct triangular with a deep anteromedial emargination and bearing a pair of dorsomedial setulae. Cercus short, triangular with 3 long sinuate setae (1 preapical, 1 lateral and 1 dorsal) and several smaller setulae. S6 and S7 also relatively well-developed, present as broad, microtrichose plates bearing posterior rows of 12–13 setae. S8 a broad posteriorly microtrichose plate with a broad anteromedial emargination, a small posteromedial tab and bearing a posterior row of 8 setae. Hypoproct broadly and deeply emarginated anteromedially with a posterior row of setae. Spermathecae elongate, balloon-shaped, and entirely smooth; stem short (0.3x length of spermatheca) and cylindrical.
Type material. Holotype: AUSTRALIA: Western Australia: Walpole– Nornalup National Park, Gully Road, pitfall traps, 25.i–6.iii.1979, G. Hangay (♂, HNHM).
Paratypes: AUSTRALIA: Western Australia: Walpole–Nornalup National Park, 25.i–6.iii.1979, G. Hangay (3 ♂, 6 ♀); same data as holotype (5 ♂, 8 ♀); Treen Brook State Forest, 25.i–6.iii.1979, G. Hangay (1 ♀). All paratype specimens in HNHM except 2 ♂ and 3 ♀ in AMSA.
Material examined. AUSTRALIA: Western Australia: 1 km E Northcliffe Park, karri forest, dung traps, 13–16.vii.1980, S. & J. Peck (1 ♂, 1 ♀, DEBU); 50 km SW Nannup, Sues Bridge, karri forest, dung cup traps, 24–26.vii.1980, S. & J. Peck (1 ♂, 1 ♀, DEBU); Mount Frankland, 30 km N Walpole, pans, 26.xi.2003, S.A. Marshall (1 ♂, DEBU); Pemberton, Gloucester Tree, karri forest, dung cup traps, 5–9.vii.1980, S. & P. Peck (1 ♂, 2 ♀, DEBU); Pemberton, Warren National Park, karri forest, dung cup traps, 5–9.vii.1980, S. & J. Peck (2 ♀, DEBU); Walpole, 15 km E, tingle tree forest, dung pans in leaf litter, 28–30.xi.2003, S.A. Marshall (1 ♂, 1 ♀, DEBU); Walpole–Nornalup National Park, tingle tree forest, “mini” carrion traps, 19.vi.–4.vii.1980, S. &. J. Peck (7 ♂, 21 ♀, DEBU); Walpole–Nornalup National Park, tingle tree forest, dung cup traps, 4.vii.1980, S. & J. Peck (6 ♂, 13 ♀, DEBU); Walpole–Nornalup National Park, tingle tree forest, dung cup traps, 18.vi–29.vii.1980, S. & J. Peck (4 ♂, 8 ♀, DEBU); Walpole–Nornalup National Park, tingle tree forest, dung cup traps, 21.vi.1980, S. & J. Peck (1 ♂, 2 ♀, DEBU); Wrenwood Cottages, 10 km NW Augusta, 34˚15’S 115˚01’E, paperbark grove, pans, 20–23.xi.2003, S.A. Marshall (2 ♀, DEBU).
Comments. Howickia flavithorax resembles the sympatric yellow morph of H. regalis (see below), and is also known from the same areas of WA. H. flavithorax can be easily distinguished by its smooth, plain frons (microtrichose striped in H. regalis), four pairs of fine interfrontal setae (three stout pairs in H. regalis), a lack of outer vertical setae, and the dark brown lower portion of the katepimeron.
This species was originally described as a species of Bentrovata based on similarities to the type species of Bentrovata, B. regalis: one pair of orbital bristles, completely reduced halters, narrow postgonites, small surstylus with an apical thorn-like seta, and reduced epiproct. However, all of these characters are also found in many other species of Howickia, and our phylogenetic analysis of the genus places these two species as distantly related. Howickia flavithorax has the tripartite hypandrium which defines Howickia, in addition to the two pairs of dorsal mid tibial bristles, male S5 with a posteromedial patch of stout setae, and bilobed surstylus with a stout apicoventral seta that are found in most species of wingless Howickia. Bentrovata is here treated as a synonym of Howickia (see comments below H. regalis).
description: Published as part of Kuwahara, Gregory K. & Marshall, Stephen A., 2022, A revision of the Australian species of Howickia Richards (Diptera: Sphaeroceridae: Limosininae), pp. 1-152 in Zootaxa 5192 (1) on pages 119-122, DOI: 10.11646/zootaxa.5192.1.1, http://zenodo.org/record/7138639