Styringomyia bipunctata EDWARDS

Theischinger, Günther, D, Zacariah & Martin, John, 2018, The genus Styringomyia LOEW in Australia (Diptera: Tipuloidea: Limoniidae), Linzer biologische Beiträge 50 (2), pp. 1587-1633 : 1596-1597

Styringomyia bipunctata EDWARDS ( Figs 33-36 )

Styringomyia bipunctata EDWARDS, 1924: 272 . Holotype ♂: Australia, Queensland, Malanda, Mjoberg ; in NRM.

M a t e r i a l s t u d i e d. Queensland: holotype (see Fig. 33 ); 1 paratype ♂, Malanda, Mjoberg ( AC) ; 1♂, 1♀, 17.37S °/ 145.34E °, B83, Massey Ck , 1000 m, malaise trap, 3-x-2-xi-1995, L. Umback ( AM) ; 1♂, Sluice Ck, 8 km W by S Millaa Millaa, 25-iv-1981, at light, D.H. Colless ( ANIC). 1♂, Mt Edith Forest Road 1 m. off Danbulla Road , 6-v-1967, D.H. Colless ( ANIC) ; 1♀, Mt Edith 4-7 m. off Danbulla Road, 27-iv-1967, D.H. Colless ( ANIC). 1♂, 1♀, 2 sn, Wongabel State Forest, 7-v-1967, D.H. Colless ( ANIC). 1♂, 1 sn, Yungaburra ( State Forest 452), 29-iv-1967, D.H. Colless ( ANIC) .

The most valuable diagnostic characters specified in the original Description of the male ( EDWARDS 1924) are: "Legs uniformly yellow, except for the extreme tips of femora and tibiae. Wings with the usual dark spots over the crossveins. Hypopygium: Ninth tergite rather short, ending in three little triangular points. Ninth sternite very long, extending beyond the tips of the side-pieces, curled into a tubular shape, truncate and slightly blackened at the tip. Terminal projection of side-pieces rather long and stout, with one rather weak spine and a number of stiff hairs, two or three of which are thickened, black and almost spine-like."

From the Description above of the hypopygium and the now available material of Styringomyia from Australia it became obvious that EDWARDS (1924) when giving a correct treatment of the dorso-ventral orientation of the male terminalia in Styringomyia did not get it right in S. bipunctata . If this is taken into account, however, the original description is sufficient for a confident interpretation of the species.

ALEXANDER (1925, 1960) mentioned S. bipunctata in comparison with S. mcgregori ALEXANDER, 1925 and with S. scalaris ALEXANDER, 1960 . The great differences between the male terminalia of these species have nothing to do with the fact that ALEXANDER identified a Styringomyia male from Brooklana, New South Wales as bipunctata ( Figs 40-43 ). This specimen is actually S. williamsi nov.sp. as described below. Whereas S. bipunctata is a tropical species, S. williamsi is known to range from Goomburra in Queensland (27.978844°S / 152.293154°E) to Minnamurra Falls (34°38’S / 152°51’E) well south of Sydney. The two are apparently a pair of allopatric species occurring north, respectively south, of the Eungella - Paluma gap, a region where ecological and physiographic boundaries coincide with taxonomic discontinuities below the level of closely related species-pairs in Odonata, Plecoptera and Megaloptera (WATSON & THEISCHINGER 1984).

D e s c r i p t i o n

Male ( Figs 33-35 )

Hypopygium. Tergite 9/10 long and wide, largely parallel sided with ear-like lateral expansions in third quarter of its length. Sternite 9 widely trapezoidal, almost hemispherical ending in three narrow lobes, the median apparently with tip triangular, the lateral ones strongly setose; two moderately long and moderately thick subapical setae. Gonocoxites evenly curved, almost conical with basal three fourths markedly expanded and with rather slim apical spine and abundant setae along mesal face, particularly at the apical end of the expansion. Gonostyli a single element represented by a slightly curved lobe triangularly expanded subbasally, with abundant setae and two large apical spines and one subapical spine bearing a secondary spine. What is detectable of the aedeagus appears moderately wide and obtusely conical.

Female ( Fig. 36 )

Head. Including rostrum and antennae yellowish to pale greyish brown, palps somewhat darker and postocular section greyish brown.

Thorax. Largely brownish yellow. Legs pale brownish yellow with extreme tip of femora and tibiae slightly darkened and last tarsal segment and claws dark greyish brown.

Wings. Infumed with pale greyish and with somewhat darker spots on crossveins.

Abdomen. Largely dull yellow with tergites almost wholly greyish brown.

Terminalia. As specified under S. bipunctata group.

Dimensions. Wing length 4.0- 4.5 mm.

D i s t r i b u t i o n. North-eastern; known only from tropical Queensland ( Map 3 ).

D i s c u s s i o n Styringomyia bipunctata , S. williamsi nov.sp. and S. coronata nov.sp. are a closely knit group of species with sternite 9 of male ending in three small extensions and tergite 9/10 very long and truncate if the 180 degrees torsion of the male terminalia in Styringomyia is correct and consistent ( EDWARDS 1924, RIBEIRO 2003) and if we can assume (based on fresh material of three species) that EDWARDS (1924) nevertheless got the dorsoventral orientation of the hypopygium wrong in the Description of S. bipunctata . S. bipunctata can be distinguished from S. williamsi , its closest ally, possible its sister taxon, by the longer, less flat and narrower median extension of male sternite 9 and by its geographical distribution (more northern, tropical) versus more southern. Both, S. bipunctata and S. williamsi have the three extensions of sternite 9 shorter and the thinner apical portion of the gonocoxites markedly shorter than S. coronata .

Figures

Map 3: Distribution of the species of the Styringomyia bipunctata group: S. bipunctata, S. williamsi, S. coronata.

Fig. 33: Styringomyia bipunctata EDWARDS, holotype male, habitus, label and terminalia inset.

Figs 34-36: Styringomyia bipunctata EDWARDS, terminalia: (34, 35) male: (34) ventral; (35) dorsal; (36) female, lateral.

Figs 40-43: Styringomyia williamsi nov.sp. (interpreted as Styringomyia bipunctata EDWARDS): (40) wing; (41) terminalia; (42) leg; (43) label.