The killer flies Coenosia Meigen (Diptera: Muscidae) of southern South America: the Coenosia chaetosa species group with two new species, and notes on male terminalia patterns Author Patitucci, Luciano Damián Author Couri, Marcia Souto Author Mulieri, Pablo Ricardo text Journal of Natural History 2021 2021-08-06 55 23 - 24 1499 1519 http://dx.doi.org/10.1080/00222933.2021.1954711 journal article 10.1080/00222933.2021.1954711 1464-5262 5469868 33F53019-E31A-45C8-B50A-2A533618C9E0 Coenosia mallochi sp. nov. Male . Length. Body: 3.18–3.37 mm , wing: 3.62–3.80 mm . Head ( Figure 4 (a, b)). Frons black with golden pollinosity, fronto-orbital plate, parafacial and gena black with grey pollinosity. Frons longer than wide, with frontal triangle long, reaching lunula. Gena with thin black hairs, and with height greater than the width of the postpedicel. Arista with its longest hairs hardly longer than its basal diameter. Thorax ( Figure 4 (c)). Black with grey pollinosity, with two fine dark-brown vittae along dorsocentral row of setae. Chaetotaxy: acrostichal setae short and strong, the anterior presutural pair as long as the eaDC; dorsocentrals 1 + 3, with a short eaDC pair which is less than one fifth of the aDC; intra-alars 1 + 2, postsutural setae similar in length; supraalars 1 + 2, the posterior seta short. Katepisternum with 1–3 setula. Wing . Tegula yellow. Legs . Coxae black with grey pollinosity and black hairs. Trochanters yellow-reddish with black hairs. Femora black with grey pollinosity, tibia yellow, and tarsus dark brown. Mid femur with a row of fine ventral setae, a row of fine setae on anterior surface, and 2 preapical setae on posterodorsal to posterior surface; mid tibia with one anterodorsal and one posterodorsal median setae, anterodorsal seta shorter and positioned below of the posterodorsal seta. Hind femur with a complete row of anterodorsal and a row of anteroventral black hairs. Abdomen ( Figure 4 (d)). Grey with sub-triangular lateral dark-brown marks on tergites 3–5. Sternite 5 with similar width and lenght, basal margin convex, apical margin strongly concave (‘V’ shape), without a membrane; setae concentrated on the lobes and a little spread over the basal margin ( Figure 4 (e)). Terminalia . Cercus longer than broad with a slightly constriction on apical third, sclerotised, setulose (hair-like seta), with apical margin concave with 2 teeth strongly sclerotised ( Figure 4 (f-h)). Surstyli longer than broad, slightly curved towards at the distal tip towards cercus ( Figure 4 (g)). Hypandrium tubular, longer than wide, without lateral prolongation, distal extreme not exposing the phallapodeme. Aedeagus with phallapodeme straight, strongly sclerotised, and a little longer than hypandrium in lateral view; pregonite developed, kidney-shaped, ventrally fused with the hypandrium; postgonite developed; epiphalus sclerotised, and distiphallus tubular, and sclerotised at base ( Figure 4 (i-j)). Figure 4. Coenosia mallochi sp. nov . , male. (a) Lateral view (Scale bar = 1 mm). (b) Head, frontal view. (c) Thorax, dorsal view. (d) Abdomen, dorsal view (Scale bar = 0.5 mm). (e) Sternite 5 (Scale bar = 0.2 mm). (f) Cercus and surstyli, posterior view. (g) Cercus, surstyli, and phallic complex, lateral view (Scale bar = 0.5 mm). (h) Detailed of distal tip of cercus (SEM). (i) Phallic complex, lateral view. (j) Detailed of distal tip of phallic complex (SEM) (Scale bar = 0.05 mm). (Abbreviations: aDC anterior dorsocentral seta; distiph, distiphallus; epiph, epiphallus; hypd, hypandrium; pgt, postgonite; phapod, phallapodeme; pregt, pregonite). Female unknown. Type material examined. Holotype male, pinned, labels: ‘Arg. Chubut , P.N. Los Alerces ,/ Cabaña La Cascasa 532 m ( Malaise )/42°53 ʹ 19,17’ S, 71°35 ʹ 34,37” W / 5-II-2013 Olea, Mulieri & Patitucci leg.” print. on white paper; ‘ MB2 ’ print on white paper, black frame, ‘MACN-En/34714’ print. on white paper. Paratypes : male, pinned, labels: Arg. Chubut , P.N. Los Alerces ,/Cabaña La Cascasa 532 m (Malaise)/ 42°53 ʹ 19,17” S , 71° 35 ʹ 34,37” W / 5-II-2013 Olea, Mulieri & Patitucci leg.” print. on white paper; ‘ MB3 ’ print on white paper, black frame, ‘MACN-En/34715’ print. on white paper; male, pinned, labels: Arg. Chubut , P.N. Los Alerces ,/Cabaña La Cascasa 532 m (Malaise)/ 42°53 ʹ 19,17” S , 71° 35 ʹ 34,37” W / 5-II-2013 Olea, Mulieri & Patitucci leg.” print. on white paper; ‘MA4’ print on white paper, black frame, ‘MACN-En/347146’ print. on white paper. Other specimens examined . ARGENTINA : Chubut : PNLP : 2 males , Río Azul , I-2012 , −42.0916 , −71.6155 , Mulieri & Patitucci leg . ( MACN ). Neuquén : PNL: 2 males , Quillen , 11- I-2013 , −39.3613 , −71.2188 , Patitucci leg . ( MACN ). Distribution ( Figure 3 (b)). ARGENTINA : Chubut , Neuquén . Etymology . The name of this species is dedicated to John R. Malloch for his great contribution to the knowledge of Patagonian Muscidae . Remarks . Coenosia mallochi sp. nov. is distinguished from its congeners by the following combination of characters: frontal triangle long, reaching lunula, visible; a short eaDC which is less than one fifth of the aDC; trochanters yellow-reddish with black hairs; mid tibia with one anterodorsal seta and one posterodorsal median seta, anterodorsal seta shorter and positioned below the posterodorsal seta; hind tibia with one long anterodorsal seta and one thin anteroventral seta; cercus longer than broad, setulose (hair-like seta); distiphallus tubular, and sclerotised at base. In Stein’s key (1911), C. mallochi runs to C. iniqua , but the presence of vittae on the scutum and spots on the abdomen can separate it from C. iniqua . In Malloch´s key (1934), C. mallochi runs to C. inaequalis , but the presence of black strong setae on coxae can separate it from the male of C. inaequalis .