Ceratomerus campbelli (Paramonov)

Bradley J Sinclair, 2003, Taxonomy, Phylogeny and Zoogeography of the Subfamily Ceratomerinae of Australia (Diptera: Empidoidea), Records of the Australian Museum 55, pp. 1-44 : 12-14

Ceratomerus campbelli (Paramonov)

Figs. 5, 6, 13, 22–24, 28, 88

Tomia campbelli Paramonov, 1961: 101 .

Type material. HOLOTYPE 3, “ Interview R. area/ N of Pieman R., Tasm./ 31 Dec. 1953 / T. G. Campbell ”; “ Tomia / campbelli/ Paramonov/ HOLOTYPE 3 [red label]”; “ Paramonov det./ Tomia / campbelli/ gen et sp. nov./ Typus 3 [hand written]” ( ANIC).

Additional material. Tasmania: 1♀, nr Candle Mtn, Pencil Pine Ck , 800 m, high woodland, pans, 30.i.1989; 233 , 4♀♀, Hartz Mtns NP, nr Keogh Falls , 23.i.1989, rock seep .; 1♀, Frodshams Pass nr Mt. Wedge, 4–5.ii.1989, rainfor., y.pans; 1 3, Mt. Bobs Range , Pine Lk., 680 m, W. Hartz Mtns , 23.i.1989, wet heath ( AMS) ; 1♀, Hellyer Gorge , 2.ii.1967 ( ANIC) ; 333, 1♀, Mt. Bobs Range, nr Pine Lk. , 700 m, 23.i.1989, rainfor., y.pans ( AMS, CNC, ZFMK) .

Diagnosis. This is the largest sized species in Tasmania, with males readily recognized by the long highly modified midlegs and processes projecting from the anal lobe of the wing. Females are separated by pale-coloured pleura and white-tipped stylus.

Description. Wing length 4.7– 5 mm, similar to C. athertonius except as follows:

Male. Head. Postocellar bristles short, one-third length of ocellar bristles; postocular bristles short, slender, overlapping less than one-third of eye. Antenna long, with scape subequal to half length of labrum; three-segmented stylus subequal to half length of postpedicel; segment 8 4–5× longer than wide; apical two-thirds of stylus white. Palpus brown, one-third length of labrum, with several long, dark setae.

Thorax. Mesonotum and postnotum dark, with 2 wide, reddish-brown stripes on either side of dc; pleura, postpronotal lobe pale. Two long anterior acrostichals, followed by alternating single row of short setulae to prescutellar depression, directed anteriorly; 4 dc, posterior dc short and slender; 2 psut spal, lower near wing base; numerous setulae scattered on scutum, particularly on pprn, among dc and npl.

Wing ( Fig. 13). Wing stem with long, undifferentiated setae; cell dm triangular. Halter with dark knob.

Legs. Coxae concolorous with pleura. Fore coxa armed on inner margin one-third before apex with tuft of stout setae and pair of long, sclerotized processes similar to a collapsed sac ( Fig. 88); distal to process, inner surface deeply concave. Fore trochanter equal to one-third of fore coxa, bearing row of 4–5 short setae. Fore femur with very long, stout basal seta; midlength of anterior region with patch of long, erect setae; pv region with row of stout setae, increasing in length apically. Fore tibia equal in length to femur + trochanter, apex dilated covered with rows of short setae and bearing anteroapical comb; basal half of anterior region with row of long, erect setae; pv region with row of stout setae, increasing in length apically. First tarsomere slightly shorter than fore tibia, with pd apical row of 5–6 stout setae.

Mid coxa with stout lateral seta and transverse row of setae on anterior face. Basal half of mid femur strongly thickened, with large av tubercle; ventral region of basal half armed with 2 long, stout setae and wide, flattened, curved seta; apical half with ad row of stout setae; ventral region of apical half with 2 long setae and short, flattened, finger-like process ( Figs. 5, 6). Mid tibia shorter than femur extremely modified by series of variously ornamented processes and setae. First tarsomere longer than remaining 4 tarsomeres.

Hind coxa with transverse row of setae on anterior face. Hind femur twice length of fore femur, bearing row of 7–9 long, flattened pv setae near mid-length; preapical seta, long, stout, projecting perpendicular to posterior surface. Hind tibia longer than femur, apex dilated, bearing posteroapical comb; subapical posterior region with shallow notch; ad region with 1 subapical seta and 2 setae on basal half; 1 erect dorsal seta near mid-length.

Abdomen brown, with long, stout setae along posterior margin of T1–6; T7 membranous.

Terminalia ( Figs. 22, 23). Hypandrium with posterior flap-like process; paired articulated, curved postgonites projecting laterally near apex of phallus. Apex of phallus with laterally projecting sickle-shaped appendages which arch anteriorly beneath postgonites. Epandrium with short pointed lobe projected anterior to surstylus. Surstylus slender, arched dorsally, parallel-sided with rounded apex, bearing setulae. Cercus short, fleshy, apex acute, expanded laterally around anus.

Female. Similar to male and female of C. athertonius except as follows: wing lacking posterior incision and appendage; medial fork with short petiole, basal to radial fork by slightly more than half length of R 4. Apex of fore tibia slightly expanded. Posterior fringe of setae on T7 restricted to lateral margins. Terminalia ( Fig. 24): T8 largely membranous, with dense fringe of setae along lateral margins; S8 with median stripe of setae. T10 bearing short, spine-like setae; cercus short with small apical spine-like setae. Spermathecal receptacle slightly oval, with duct attached directly, lacking pigmented ridge or neck-like extension.

Distribution. This species is restricted to the moist, higher elevations of the western half of Tasmania ( Fig. 28).