Fannia pretiosa -group species from Mexico

Diagnosis. Body metallic black-bluish to dark grey with silver pruinosity. Eyes short setulose. Parafacial bare. Scape and pedicel black. Postpedicel 3 times longer than pedicel. Arista black, with short pubescence, rays shorter than width of base of arista. Palpus black and slightly spatulate apically. Prealar 2. Proepimeron with 2 setae and covered with setulae. Notopleural 2. Postpronotum with 2 setae and covered with setulae. One pair of prescutelar setae. Dorsocentrals 2+3. Katepisternum 1+1. Male legs: fore femur very setulose on p surface, with 1 row of long pv and pd; ad to v surface bare; fore tibia with 1 pre-apical d; 1 short apical pv and v; fore tarsi white-yellowish (except F. arcuata and F. bisetata sp. nov.); mid tibia constricted ventrally on basal half, enlarged and covered with several ventral setulae on apical half; hind femur with pre-apical swelling on v surface, covered with a tuft of long posteroventral setae ( F. amplitarsis sp. nov., F. bisetata sp. nov., and F. grisalesae sp. nov. also have an anteroventral tuft of setae); hind tibia with 1 long submedian d seta (with a third of the tibia length), 1 submedian ad ( F. amplitarsis sp. nov., F. arcuata, F. bisetata sp. nov. also have a full row of short ad setae), and 1 pre-apical d shorter (about half-length of the longer one). Sternite 1 setulose (densely setulose in F. bisetata sp. nov.). Male syntergosternite with 2–5 lateral setae. Male terminalia with long and curved surstyli and a long bacilliform process (Fig. 4).