Heteromeringia magnicauda, Lonsdale, 2009

Lonsdale, Owen, 2009, The Heteromeringia (Diptera: Clusiidae: Clusiodinae) of Australia, Records of the Australian Museum 61 (3), pp. 229-262 : 250-251

Heteromeringia magnicauda n.sp.

Figs 54–57

Type material. HOLOTYPE: New South Wales: Tahmoor , 28.x.1981, B.J. Day (1♂, AMS) . PARATYPES: New South Wales: nr. Hartley Valley , 22.xi.1993, ex. dry sclerophyll tree trunks, B.J. Sinclair (1♂, CNC) , Heathcote N.P., Kingfisher Pool , 16.x.1994, B.J. Sinclair, ex. dry eucalypt for. (1♂, CNC) , Hartley Vale Rd., Blue Mountains , 26.x.1993, on smooth Eucalyptus bark, D.K. McAlpine & B.J. Day (2♂♂, AMS) , 8km S Mt. Wilson, Blue Mts. , 27.ix.1989, D.K. McAlpine (1♂, DEBU; 1♂, USNM) . Queensland: Sluice Ck., 8km W by S Millaa Millaa , 25.iv.1981, D.H. Colless, at light (1♂, ANIC) .

Description

Male. Body length 2.4–3.0 mm. Anepisternal disc present. First flagellomere recessed dorsally and lobate ventrally (as in Figs 3, 4 ). Bristles black. Arista pubescent. Vibrissa short and straight. Ocellar bristle long and thin. Two long dorsocentral bristles with small bristle in front of anterior dorsocentral. Gena high and sharply incurved medially at mid-height. Face and buccal cavity evenly blending and velvety. Frons dark brown with anteromedial margin orange to yellow (colour sometimes extending along lateral margin) and lateral and posterior margins yellowish; first flagellomere with infuscation at base of arista; occiput, back of head and posteroventral corner of gena dark brown; dorsal half of face light yellow; buccal cavity, anterior portion of frons and dorsal 4 ⁄ 5 of gena pilose; mentum sometimes dark brown. Thorax dark brown. Fore tibia dark brown on distal 2 ⁄ 3 and fore femur light brown (darker on basal ¾– 6 ⁄ 7) with knee yellow; fore coxa brownish at base; fore tarsi (ovate in cross section) yellow with distal two tarsomeres light brown (QLD specimens with all segments brown); dorsal margin of mid coxa brown to orange; mid and hind femora brown medially, mid tibia brown medially on inner face and hind tibia brown on basal half (sometimes mid and hind femora and tibiae entirely brown excluding base and apex); hind coxa brown; remainder of legs yellow. Abdomen dark brown. M 1+2 ratio 6.4. Wing with anterodistal infuscation. Halter white with base and side of stalk infuscated.

Female. Unknown.

Male terminalia ( Figs 54–57 ). Epandrium bulbous and larger than pregenitalic segments. Cerci rounded laterally and with apex narrow and emarginate. Surstylus triangular and strongly narrowed apically; bare on outer face and with inner-distal tubercle-like bristles. Phallapodeme relatively long and stout. Hypandrium+pregonite setulose medially and distally with two stout anteromedial bristles (inner-distal face with additional stout bristle); flat along anterior face and with suture on distal 1 ⁄ 3; distal margin notched. Basiphallus with dorsal process at point of attachment to distiphallus and fused to hypandrium+pregonite posterolaterally. Ribs of distiphallus of equal length, fused medially and with one pair of small membranous wings.

Etymology. The specific name refers to the strikingly large (Latin magnus) male genitalia (Latin cauda) of this species.

Comments. Although the male genitalia of this species are incredibly diagnostic—particularly the bulbous male epandrium—the only other potentially autapomorphic character is relatively pale fore tarsi. The fore tarsi are brown in the male from Queensland, however, and they are potentially brown in the as yet undiscovered females, since female Heteromeringia are often darker than their respective males, particularly on the fore legs. This suggests the possibility that females of H. magnicauda are inseparable from those of the similar H. laticornis .

Figures

Figures 47–57. Figs 47–49: male terminalia, Heteromeringia laticornis McAlpine; (47) external, left lateral; (48) external, posterior; (49) hypandrial complex, left lateral. Figs 50–53: male terminalia, Heteromeringia macropa n.sp.; (50) external, left lateral; (51) external, posterior; (52) phallapodeme and phallus, anterior; (53) hypandrial complex (distal portion of distiphallus removed), left lateral. Figs 54–57: male terminalia, Heteromeringia magnicauda n.sp.; (54) external, left lateral; (55) external, posterior; (56) phallus, anterior; (57) hypandrial complex (distal portion of distiphallus removed), left lateral. Scale bar = 0.25 mm.

Figures 1–8. Figs 1 and 2, head, Heteromeringia spinulosa McAlpine; (1) left lateral; (2) anterior. Figs 3 and 4, head, H. hardyi McAlpine; (3) left lateral; (4) anterior. Figs 5–7: wings; (5) H. spinulosa; (6) H. hardyi McAlpine; (7) H. australiae Malloch; (8) H. australiae, tentatively included NSW female.