Sigaloethina phaia, Munari, 2004

Munari, L., 2004, Beach Flies (Diptera: Tethinidae: Tethininae) From Australia and Papua New Guinea, with Descriptions of Two New Genera and Ten New Species, Records of the Australian Museum 56 (1), pp. 29-56 : 47-48

Sigaloethina phaia n.sp.

Figs. 23–26

Type material. HOLOTYPE 3 Australia, New South Wales “ Mangroves / Careel Bay, / Avalon , NSW. / 3 Feb. 1973 / D.K. McAlpine // HOLOTYPUS / Sigaloethina phaia / gen. n., sp. n., 3 / L. Munari des.” AM K186743 . The specimen is in excellent condition, and is double mounted (glued on the tip of a triangular card label); abdomen dissected and stored in glycerol in a small plastic tube, and pinned below the specimen . PARATYPES Australia, New South Wales: same data as holotype, 333 11♀♀; “Careel Bay / N. South Wales / 27 Oct. 1962 // Mangroves / D.K. McAlpine ”, 1 3; ibidem, “ 14 March 1963 ”, 1 ♀; “Careel Bay, / Avalon, NSW. / 15 Dec. 1964 / D.K. McAlpine // Mangroves”, 1 3; ibidem, “ 26 Dec. 1964 ”, 1 3; “North Creek, near / Ballina, NSW. / 1 March 1965 / McAlpine & Lossin”, 1 ♀; “Mangroves, Nth / Cronulla, NSW. / 21 Jan. 1962 / D.K. McAlpine ”, 13; “ NSW: Towra Pt., / Botany Bay ; 29– / iii–1986; Bickel

/ mangroves”, 1 3. Australia, Northern Territory: “NT: Buffalo Ck, / Darwin; 2–5 Mar. / 1996; D.K. McAlpine, / G. R. Brown”, 1 3 1♀. The holotype and most of the paratypes are deposited in AM , some paratypes are preserved in MCV .

Description. Size. Body length 2.1 mm (1.6–2.3), wing length 2.1 mm (1.5–2.3), wing width 0.8 mm (0.5–0.8).

Habitus ( Fig. 23). Dark brown species having glossy cuticle, generally covered with thin, greyish microtomentum. Wings yellowish grey. Head. Dark brown, except for anterior surface of frons, antenna, face, parafacial, and gena being yellow; frons without discernible golden patch on both sides of ocellar triangle, or, if weakly present, absolutely not contrasting with rest of glossy, dark surface; paravertical setae thin, strongly inclinate; inner vertical seta inwardly curved, strong, about as long as lateroclinate outer vertical seta; postocular setae relatively long and strong, arranged in single row; upper postocular seta long, inclinate towards inner vertical seta; ocellar triangle bearing pair of thin pseudopostocellar setae in addition to pair of strong ocellars; 3 strong orbital setae, mid one distinctly lateroclinate, anterior and posterior setae more weakly lateroclinate to posteriorly directed; orbital vitta, apart from strong orbitals, almost entirely bare, at most with very few, thin setulae; 2 pairs of frontal setae, posterior pair with short, thin setae (some paratypes bear 1 to 3 pairs of such setae), anterior pair (in most paratypes equivalent to mid pair) with setae cruciate at apex; antenna with pedicel bearing very long dorsal seta, and postpedicel with arista bearing several long hairs; eye densely micropubescent, large, subrectangular, its longest diameter 8.2× as long as genal height; 7 black peristomal setae, four anteriors, including vibrissa, distinctly spaced, strong and long; shining knob above vibrissal angle absent (like Dasyrhicnoessa ); mouth parts yellowish, with labellum small and stumpy, and palpus long and slender, bearing few black setulae. Thorax. Entirely dark brown, noticeably glossy, with setal vestiture black, mostly covered with light grey microtomentum; 1+3 dorsocentral setae; 4 rows of acrostichal setulae on entire length of scutum; prescutellar acrostichals long and thin; postpronotal lobe bearing 3 setae, each with different inclination, posterior seta very long and strong, anterior setae shorter and weaker; 1 long presutural seta; 2 notopleurals subequal in length; 1 supra-alar, below it 1 shorter seta; 2 postalars, external one very long; scutellum bare, except for usual 4 long marginal setae; both proepisternal and proepimeral setae present, latter seta distinctly thinner; anepisternum with scattered pubescence, bearing 2–3 long, posteriorly directed, posteromarginal setae, mid one distinctly longer and stronger, and 1 erect, thin seta at posterodorsal margin; katepisternum with scattered pubescence, bearing long, erect, posterodorsal seta; anepimeron, katatergite, and meron without setae and setulae. Legs. Evenly setulose, bearing short blackish setae and setulae, except for foreleg having coxa with long black setae, and femur with very long, markedly spaced, posterodorsal and posteroventral setae; fore femur having vestigial ctenidium, at most with 1–2 spine-like setae (among the paratypes there are specimens without evident ctenidial spinulae, only with few, spaced, thin setae; conversely, a few other specimens show 1–4 weak, spaced spinulae which could represent the rudiments of a true ctenidium); mid femur of male with row of robust, subequal in length, posteroventral, spinelike setae arranged on entire length of femur; all legs show yellow coxae, dark brown femora, yellowish brown to yellow tibiae, and yellow tarsi; fore and hind femurs of male slightly swollen. Wing. Veins brownish yellow, membrane yellowish grey; alula with fringe formed by erect, blackish setae; costal vein reaching end of M 1 (sometimes as faint segment), bearing microscopic setulae on both dorsal and ventral surfaces; R 2+3 slightly bisinuate, diverging from R 4+5 distally; R 4+5 and M 1 parallel; crossvein r-m ending before middle of cell dm; crossvein dm-cu distinctly shorter than one third of last section of CuA 1; halter yellowish. Abdomen. Shining, black, with narrow, apicomarginal, pale brownish stripe on each tergite; tergites bearing several black setae and setulae. Male terminalia ( Figs. 24–26).

Epandrium broad, bearing sparse setae on posterior surface, few of them long and strong, in particular on dorsal surface and on posteromarginal part of distal half; cercus of normal size, pubescent, covered with microscopic hairs and with long setae dorsally; anterior surstylus arising from lower part of epandrium, distinctly larger than posterior surstylus, vaguely subtriangular, with external angles broadly rounded, its transverse axis almost perpendicular to longitudinal axis of epandrium, bearing patch of close microtrichia forming triangular area on outer surface, and with numerous, stout tubercles on posterior inner side; posterior surstylus simple, elongated, broadly rounded apically, bearing several stout tubercles on inner side; aedeagal apodeme long, bisinuate proximally; ejaculatory apodeme with broad distal fan; phallus ( Fig. 26) relatively short; distiphallus with basal half distinctly sclerotized, bearing many spine-like papillae, distal half bearing strongly diaphanous membranous lobe, and with unusual, partly sclerotized folding zone dividing phallus in two halves.

Female. Similar to male, except for very slight sexual dimorphism. Female terminalia. Cerci slender, narrow, bearing setulae dorsally and apically; spermathecae spherical, smooth.

Distribution. Australia (NSW, NT).

Remarks. The two specimens from Buffalo Creek (Northern Territory) are smaller than the other paratypes from New South Wales. However, the male terminalia are similar and I regard the specimens from both areas as conspecific.

Etymology. From the ancient Greek phaios meaning dusky or brown. The specific epithet refers to the dark brown colour of the new species.