Heteromeringia imitans Malloch, 1930

Lonsdale, Owen, 2009, The Heteromeringia (Diptera: Clusiidae: Clusiodinae) of Australia, Records of the Australian Museum 61 (3), pp. 229-262 : 247

Heteromeringia imitans Malloch, 1930

Figs 96–98 Heteromeringia imitans Malloch, 1930: 435 . D.K. McAlpine, 1960: 72. Sasakawa, 1966: 97. Heteromeringia immitans Frey, 1960: 23 .

Type material. HOLOTYPE: Queensland: N Queensland, Cairns, 1907, coll. Liechtwardt (1♀, DEI).

Additional material examined. New South Wales: E NSW, Royal National Park, Otford / Werrong trck, 13.x.2002, 34.13S / 151.01E, diff. types forest, sandy/strony[sic] beach, B. Merz (1♀, MHNG) . Queensland: N QLD, Middle Claudie Riv., Iron Range, G. Daniels , 16.ix.1974 (1♀, AMS) , 7.x.1974 (1♀, AMS) , 15.10S 145.07E, 3.5km SW by S of Mt. Baird , 4.v.1981, D.H. Colless (1♀, ANIC) , 12.43S 143.17E, 9km ENE of Mt. Tozer , 5–10.vii.1986, D.H. Colless (1♀, ANIC) .

Type 2 females. New South Wales: Carrai SF, 30°59'45"S 152°16'23"E, 930 m, E. Tasker, 3–8.xii.1997, sticky trap on E. campanulata, CS-FZ-127- 6 (1♀, AMS; 1♀, DEBU), Carrai SF, 31°00'19"S 152°16'24"E, 940 m, E. Tasker, 11–16.i.1998, sticky trap on E. campanulata, CS-GP-018-4 (1♀, AMS) , Werrikimbe NP, 31°12'00"S 152°09'00"E, 1060 m, E. Tasker, 1–7. xii.1997, sticky trap on E. viminalis, WC-MR-127-6 (1♀, AMS) , Tinda Creek, Putty Rd. , 19.x.1993, D.K. McAlpine & B.J. Day (1♀, AMS) .

Type 3 females. Queensland: 15.03S 145.09E, 3km NE of Mt. Webb, 30.iv.1981, D.H. Colless, at light (1♀, ANIC), 4km N Cardwell, Edmund Kennedy N.P., 28.iv.1994, ex. coastal for., B.J. Sinclair (1♀, CNC), The Boulders nr Babinda, 27.i.1991, McAlpine & B. Day (1♀, AMS) .

Redescription

Male. Unknown.

Female. Body length 3.4–4.5 mm. Bristles black. First flagellomere orbicular. Arista pubescent. Vibrissa relatively long and curved. Ocellar bristle long and thin. Two dorsocentral bristles. Gena neither high nor strongly incurved. Face and buccal cavity lightly pilose and slightly curving. Head dark brown with anterior margin of frons sometimes orange (non-types), pedicel and scape orange, first flagellomere light yellow with anterior margin and distal 2 ⁄ 3 of inner face dark brown, and dorsal half of gena dirty orange and silvery tomentose; anterior 1 ⁄ 3 of frons pilose medially. Thorax dark brown. Legs yellow with apex of fore femur dark brown, fore tibia and tarsi dark brown, and coxae and base of femora white. Fore tarsi strongly compressed laterally. Abdomen dark brown with terminalia yellow. M 1+2 ratio 8.0; length between cross veins approximately as long as dm-cu. Wing darkly clouded (fading past midpoint of third radial cell). Halter white with stalk and base of knob black.

Female terminalia (Fig. 96). Ventral receptacle broadly rounded with flagellum long and straight. Spermatheca longer than wide, rounded at ends, slightly wrinkled along inner-basal surface and with pale speckles medially.

Variation

AMS females differ as follows: head entirely dark brown to black; palpus approximately twice as high; terminalia entirely dark brown.

“ Type 2” females differ as follows: palpus small and thin (nearly cylindrical in cross section); knob of halter white

(possibly brown in two specimens); legs dark brown with fore coxa and basal half of fore femur white, base of mid and hind femur white, and mid and hind tibiae sometimes paler with distal ¼ yellow; first flagellomere black, usually with base and inner-ventral margin yellow; face, parafacial and anterior half of gena sometimes yellowish-orange and only base of fore femur yellow; spermathecae without “freckles”, slightly wider at base and with subapical flagellum coiled (Fig. 97).

“ Type 3” females differ as follows: ocellar bristle as long as ocellar tubercle; relatively well developed setula (c. 1 ⁄ 3 length anterior dorsocentral) in front of anterior dorsocentral; body (including halter in ANIC and CNC specimens) almost entirely dark brown with inner half of mid coxa yellow, antenna (excluding arista) yellow with first flagellomere black on anterior margin and inner-distal half, mid and hind tibiae dark yellow with base darker, and mid and hind tarsi yellow; frons shiny; wing dusky along anterodistal margin; M 1+2 ratio 4.6. Sternite and tergite 8 entirely fused; sternite 8 with two small, overlapping, unpigmented posteromedial circles. CNC female paler: legs yellow with mid and hind coxae brown and fore tarsi, tibia and inner-distal spot on fore femur dark brown; parafacial rusty and apex of palpus yellow; spermathecal duct (Fig. 98) nearly twice length of that in ANIC female.

Comments. D.K. McAlpine (1960) mentioned that the stalk of the halter is brown in this species, but it appears to be blacker in hue with the pigment extending to surround much of the base of the knob. Most other Australian Heteromeringia with a completely or predominantly dark thorax have the stalk tinged with brown, at least basally; similar brown pigmentation is found in all Afrotropical species and several Oriental and Oceanian species, although the colour is usually also restricted to the base.

In addition to the “typical” Heteromeringia imitans females described above, there are eight additional females representing two distinctly different morphologies. While these females may belong to separate species, the striking variation characteristic of Old World Heteromeringia demands that extra caution be taken when delineating lineages represented by females alone. In “ type 2” females, the head is most distinct: it is almost entirely black, excluding the scape, pedicel, and (sometimes) the base of the first flagellomere, as well as either the mentum and labellum or the face and anterodorsal margin of the gena. The head is also relatively round and shiny (excluding a dorsal pilose stripe on the gena) and the palpus is very thin and cylindrical. A similarly thin palpus is only otherwise seen in H. trisetosa , H. helina , some H. spinulosa and the species related to H. laticornis , but the presence of a coiled (not straight) flagellum on the ventral receptacle would seem to exclude any relationship with these species. “ Type 3” females also have entirely dark forelegs and an entirely dark and shiny head, although the antenna is yellow with the anterior margin and inner-distal half of the first flagellomere is black. The rest of the body is also very dark, excluding parts of the mid and hind legs, and there is a relatively well developed setula in front of the anterior dorsocentral (approximately 1 ⁄ 3 length of anterior bristle).