Genus Midacritus SeguyMidacritu8Seguy, 1938: 269. Type-species, stuardoanusSeguy (orig. des.). Head in anterior view about one and one-third times as broad as high; face at antennae about one-third width of head; oral margin at about' one-third distance from lower eye margin to antennae. Proboscis similar to Messiasia J labella slightly shorter than oral cavity; palpi slen­ der and about one-half length of oral cavity. Antennal segment 1 cylindrical and about two times as long as broad; 2 about one-half length of 1 and slightly broader than long; 3 slender and about two times as long as 1-2; club subequal in length to 3, spherical and about two-thirds as broad as long (Fig. 20). Mesonotum pollinose, denser on lateral margins and dorsocentral stripes, hairs short recumbent, longer anteriorly. Scutellum with short, sparse, recumbent hairs. Postscutellum slightly rugose, densely pollinose, bare. Pleura pilose on episternum-1, pteropleura and metasternum. Abdominal tergite-1a rounded, densely pollinose, bare; lp with long, dense hairs parted at middle and directed laterally; remainder with sparse recumbent hairs; bullae (Fig. 48) small, oval, about one and one-half times as long as broad. Sternites with sparse recumbent hairs; d' sternite 8 about one-half length of 7 and with a few apical hairs. Female with apical circlet of strong spines, numerous retrorse hairs on segments 7-8, longer on 8. Male genitalia (Figs. 93-95): hypandrium completely coalesced with basistyli; inferior region of the resulting structure very short, the apical processes very long, in such a manner that most of the aedeagus is left uncovered; apical processes of gonopods with a subapical tooth directed inwards; aedeagus voluminous, laterally compressed; epandrial halves completely free, and remarkably elongate, ending in a pointed beak, with a short spine; cerci elongated, almost parallel-sided, completely free. This type of genitalia suggests a strong modification of that of Apiophora Philippi - all the parts have become elongated, and the epandria have undergone a strong modification, reminding one of the genitalia of a Culicidae. Legs slender; hind femora about seven times as long as broad, venter with about 15 sharp spines; hairs short recumbent, semi-erect on dorsum. Hind tibiae cylindrical, with one strong and one weak apical bristle. Hind metatarsus about three times as long ·as broad and slightly longer than segments 2-3.. Alulae with fringe of very short, squamose hairs. Wings about three times as long as broad; second submarginal cell broadly open; posterior crossvein present; axillary lobe as broad as long; ambient-vein complete. Length: 14-20 mm. Geographic range: Chile.

Published as part of J. Wilcox & N. Papavero, 1971, The American Genera of Mydidae (Diptera), with the Description of three new Genera and two new Species, pp. 41-119 in Arquivos de Zoologia 21 (2) on pages 91-92, DOI: 10.5281/zenodo.154004