Austrothaumalea spiculata Pivar

Pivar, Robert J., Moulton, John K. & Sinclair, Bradley J., 2016, A new species of Austrothaumalea Tonnoir from Australia (Diptera: Thaumaleidae), Zootaxa 4132 (4), pp. 594-597 : 595

Austrothaumalea spiculata Pivar sp. nov.

Type material. HOLOTYPE ♂, labelled: “AUS: Victoria: Grampians N.P./ MacKenzie Falls, 14.ix.2014 / S37°06ʹ37.05″ E142°24ʹ31.39″/ ex. side seep along foot bridge/ to MacKenzie Falls, elev. 378m / J.K. Moulton”; “ HOLOTYPE / Austrothaumalea / spiculata / Pivar [red label]” (AMS). PARATYPES: 2 ♂, same collection information as holotype ( CNC, USNM). One additional ♂ paratype was used for molecular study and the voucher specimen is housed in the UTK Insect Museum.

Recognition. Austrothaumalea spiculata is readily distinguished from all other species by its spearhead-shaped paramere, arched gonostyli and absence of apical epandrial processes.

Description of male (female unknown).

Colouration: Head dull, dark brown; pronotum dark brown; postpronotum pale brown; mesonotum and pleura brown and somewhat shiny; katepisternum reddish-brown; legs pale yellow, becoming darker on apical tarsal segments; scutellum and mediotergite pale brown, shiny; halter stalk cream colored, knob dark; abdomen dark brown; terminalia pale brown.

Wing (Fig. 1A): Wing length: 2.7–2.9 mm. Slightly more infuscate dorsal to vein M1, with darkening where R4+5 and M1 meet wing margin, and slightly basal to R2+3; R1(+R2+3) with macrotrichia along entire length, remaining veins bare; R 2+3 situated towards apex of R 1; bend in R 4+5 well defined; R 4+5 and M 1 running parallel toward wing margin; CuA with short basal appendage.

Abdomen (Fig. 1B): Abdominal sternite 1 narrow, spectacle-shaped; sternite 2 reduced to slender, median sclerite, with pair of small, posterolateral sclerites, setae restricted to apical fourth and between posterolateral sclerites; sternites 3–6 rectangular, anterior margin well sclerotized, with pair of small, posterolateral sclerites, sternite 3 with setae on posterior two-thirds, sternites 4–6 with setae on median third; sternite 7 trapezoidal-shaped, with posterior marginal setae; sternite 8 triangle-shaped, without setae.

Male terminalia ( Figs 2 A, B): Epandrium broadly triangular from ventral aspect; apical third slightly tapered; posterior margin broad and rounded; lacking pointed posterolateral processes; light scar visible in lateral view when cleared. Hypandrium broad, nearly subequal to width of base of gonocoxites; anterior margin slightly concave. Gonocoxite broad, inner margin of basal two-thirds slightly serrated before becoming widest two-thirds of way down; apical third strongly tapered. Gonostylus nearly subequal in length to gonocoxite, curved strongly before mid-length; thickest at mid-point; gradually tapered to blunt tip. Parameres distally fused, half length of epandrium, rod-like with subapical lateral expansions creating spearhead-like apex. Gonocoxal plate broad basally; apical margin concave with short, pointed posterolateral process; basally not fused to hypandrium.

Distribution. Known only from the type locality (Fig. 1C). Grampians National Park is located in the southwest region of Victoria, roughly 260 km west of Melbourne. It consists of sandstone mountain ranges and eight different vegetation communities. Situated in the northern half of the park, Mackenzie Falls is Victoria’s highest waterfall. Austrothaumalea denticulata Theischinger is the only other species of thaumaleid known from the Grampians ( Theischinger 1986).

Etymology. Austrothaumalea spiculata is so named from the Latin, spica (point), in reference to the shape of the paramere, which resembles that of a Roman spear.

Modified key from Sinclair (2008b)

Austrothaumalea spiculata keys to couplet 20 in Sinclair (2008b). This couplet is modified as follows:

20 Paramere with pair of slender coiled processes............................................................................................ A. simplex Theischinger - Paramere without pair of coiled processes ................................................................................................................................... 20a 20a Paramere with subapical, lateral expansions, spearhead-like in appearance .................................................... A. spiculata sp. nov. - Paramere simple, straight, lacking expansions or processes .......................................................................................................... 21

Figures

FIGURE 2. Male terminalia of Austrothaumalea spiculata sp. nov. in (A) ventral view and (B) lateral view. Scale bar = 0.1 mm. Abbreviations: cerc, cercus; epand, epandrium; gcx, gonocoxite; gcx pl, gonocoxal plate; gst, gonostylus; hypd, hypandrium; pm, paramere.