Figs 153–155, 171, 172, 191

Diagnosis. Ecnomina merki closely resembles other species in the group, but it is distinguished by widely separated pair of processes on tergum X and disto-lateral projections on the inferior appendages.

Description. Head, body and wings light brown to fawn, abdomen paler ventrally; wings (Fig. 172) similar to E. legula (Fig. 3). Forewing length about 2.7–2.8 times width: male 2.7–2.9 mm, female 2.8–3.0 mm. Forewing fork 2 relatively long, sessile, length about 1.5–1.8 times length of fork 3; fork 3 relatively short, with long footstalk, length fork about 1.6–2.2 times length footstalk, footstalk length about 1.6–2.5 times length cross-vein m, r-m and m nearly contiguous at footstalk fork 3, r-m and m separated by about 0.5–0.7 times length of cross-vein m; fork 4 slightly shorter than fork 3; fork 5 long, length about twice length of fork 4. Hindwing length about 3.0–3.2 times width, fork 2 sessile or with short footstalk, length fork footstalk about 0–0.4 times length cross-vein r-m, fork 2 length about 1.7–1.8 times length of fork 3.

Male. Tergum X membranous, with one pair of relatively short, simple dorsal processes, widely separated (Fig. 155). Superior appendages in lateral view, sub-rectangular, length about 3.5 times width (Fig. 153); in dorsal view, length about 6 times width, with several spines and short processes meso-distally (Fig. 155). Phallus simple, slender, tube-like, with a pair of basally directed spines near middle (Fig. 153). Inferior appendages short; in ventral view, fused in basal two thirds, dilated distally and with pair of disto-lateral projections, with oval excision meso-distally, length about same as width (Fig. 154); in lateral view, slender, length about five times width (Fig. 153).

Female. Genitalia with a single elongate and slender mesal process, slightly bulbous basally, on sternite VIII; segment IX relatively long, tapered slightly distally, segment X relatively short and segments IX and X relatively slender (Fig. 191).

Holotype male: Western Australia, Camp Ck, Mitchell Plateau (about 14°50'S, 125°50'E), lt tr., 29 Feb 1978, J.E.Bishop (NMV, T-19846).

Paratypes: Western Australia. 1 male (specimen CT-473 figured), same loc. and coll., 26 Feb 1978; 3 males, 6 females (specimen CT-514 figured), same loc. and coll., 31 Jan 1978; 4 males, 2 females, same loc. and coll., 30 Jan 1978 (NMV).

Etymology. Merki - Australian Aboriginal word for small hole (inferior appendages).

Remarks. Ecnomina merki has been collected only from the type locality in northern Western Australia (latitude 14°50'S).