(Figs. 6, 15, 23)

Type species: Chrysotus saxatilis Grimshaw, 1901, by present designation.

Diagnosis: Similar to Sigmatineurum in having a ventral posteromedial process on the fourth sternite, but can be distinguished by the wing with the CuAx ratio about 1 (this ratio> 2.5 in Sigmatineurum) and the hypopygium with basiventral epandrial lobe long, thin, slightly sinuous, of even width to apex (this lobe long, thin, and clavate apically in Sigmatineurum). Additionally, species of Elmoia are generally much smaller in size (body length 2–3 mm in length) than Sigmatineurum (body length 5–7 mm in length).

Description: Male. Body length: 1.8–3.6 mm. Wing length: 2.2–4.0 mm. Head. Shining metallic; face slightly narrower than distance between lateral edges of antennal sockets (cf. Fig. 3), tapering below antennae, then parallel to clypeus; clypeus small, ventral margin well above lower margin of eyes; palpi not extending below eyes. Antennae with first flagellomere short, conical, rounded apically, length subequal to width; arista dorsal, with micropubescence along entire length. Ocellars normal in size, length ca. 1/4 head height; verticals present, erect. Thorax. Shining metallic dorsally, pleura subpollinose. Chaetotaxy as follows: 5 dc; 2 np; 1 ph; 1 pa; 1 sc; 2 sa; ac absent. Legs. Coxa I with sparse fine setae along anterior surface, apically with long bristles; CII and CIII with strong lateral bristle. All femora with fine setae; fore femur with strong ventral bristles. Anterior preapicals only on FII and FIII. Tibia II and TIII with strong bristles. Claws normal in size (cf. Fig. 12b). Wing (Fig. 15). With sparse microtrichia giving wing a subhyaline appearance. CuAx ratio about 1. Abdomen. Shining metallic dorsally, pollinose on sternites. Segments I–V subequal in size; posterior margins of tergites I–VI with longer hairs than elsewhere but not conspicuously strong, fine hairs dorsally and laterally. Sternum IV with posteromedial process. Tergite V extending ventrally to below level of tergite IV. Hypopygium (Fig. 23). Subtriangular, extending forward to middle of tergite V; cercus rounded with small anteroapical process, with numerous setae, longest apically; surstylus unilobed, with sparse short fine hairs apically; basiventral epandrial lobe long, thin, slightly sinuous, evenly wide throughout entire length, with hairs apically; hypandrium long, length about 4 x width, with small recurved hook­like apex.

Female. As in male except for abdominal modifications and genitalic features; legs normal, without modifications.

Discussion: In addition to the smaller size and other morphological characters given above used to separate Elmoia from Sigmatineurum, their generally non­aquatic habits (found on leaf litter, low­growing vegetation, and the forest floor) will also separate them from species of Sigmatineurum, which are found along swift moving streams or on the vertical surfaces of seeps.

Included Species: Elmoia bullata (Hardy & Kohn) *, comb. n., E. exartema (Hardy & Kohn) *, comb. n., E. hamata (Hardy & Kohn) *, comb. n., E. lanceolata (Tenorio) *, comb. n., E. multispinosa (Hardy & Kohn) *, comb. n., E. nigrohalterata (Hardy & Kohn) *, comb. n., E. saxatilis (Grimshaw), comb. n., E. viridifacies (Van Duzee), comb. n.

Etymology: The genus­group name honors the late Prof. D. Elmo Hardy, for his generous advice and continuous encouragement during my years as a student under his tutelage and for the tremendous increase in knowledge of Diptera of Hawai‘i he provided through his years of study of the group. Gender is feminine.