Review of selected species of Campsurus Eaton 1868 (Ephemeroptera: Polymitarcyidae), with description of eleven new species and a key to male imagos of the genus Molineri, Carlos Salles, Frederico F. Zootaxa 2017 4300 3 301 354 Molineri & Salles, 2017 Molineri & Salles 2017 [151,396,151,177] Insecta Polymitarcyidae Campsurus Animalia Ephemeroptera 20 321 Arthropoda species pereirae sp. nov.     Typematerial. Holotype ♂i from BRAZIL, Goiás, Parque Nacional das Emas,  26.ii.2012, S 18°15'40"/ W 52°53'18", LF Sgarbi, APM Santos, E. Raimundi cols. ( CZNC). Paratypes: 1 ♂i same data as holotype (IBN).   Additional material. BRAZIL: 1 ♀i from Goiás, Mineiros, riacho/ponte, L  22, 514 m, S 17° 12' 36"/ W 52° 39' 39",  24.ii.2012, pennsylvania light trap, LF Sgarbi, APM Santos, E. Raimundi cols. ( CZNC). SURINAM: 3 ♂i ( FAMU, except 1 ♂i IBN759CM) from Brokopondo district, creek on N edge Brokopondo(approx. N5° 0'/ W 54° 59'),  90 m,  27.xii.1978, WL & JG Peterscols. Male imago. Length (mm): body, 6.0–6.5; fore wing, 6.0–7.0; hind wing, 2.9; cerci, 17.0–20.0; fore leg, 3.6. General coloration yellowish, widely shaded with gray ( Fig. 169). Head completely shaded with black dorsally, brownish gray on gena, antenna (except for hyaline flagellum) and ventrally. Thorax ( Fig. 169). Pronotum translucent, completely shaded with gray, darker on anterior portion, medial line, and margins; prosternum yellowish white, shaded with gray; propleura anteriorly grayish, posteriorly black. Mesonotum yellowish, shaded with gray on medial line, parapsidal sutures, and between PSP; pleura and sterna yellowish white, shaded with gray; sutures above coxa blackish; furcasternum shaded with gray. Metanotum yellowish white, shaded with gray medially. Legs. Fore leg completely shaded gray, slightly paler at base of tarsomeres; middle and hind legs whitish, shaded completely with gray. Wings. Membrane hyaline, except C and Sc areas shaded with brownish gray, veins hyaline, except C, Sc, and R1 brownish. Hind wing hyaline, except C and Sc areas very slightly shaded with gray. Abdomen ( Fig. 169) whitish translucent, widely and strongly shaded with gray on terga, except on pleural folds. Abdominal sterna translucent white, shaded with gray, slightly darker on medial line and inner margin of gill sclerites. Genitalia ( Figs. 71–74): yellowish white; sternum IX with truncate hind margin ( Fig. 71), medial line and hind margin black; pedestal of each side touching basally, with apically acute parastylus (not visible in Fig. 72), round inner corner strongly projected; forceps short and translucent, shaded with gray; base of main lobe of penes sclerotized, strongly expanded laterally and proximally, with dorsal surface finely granulated (arrow in Fig. 73), apical 1/3 narrowing abruptly, rounded and curved ventrally ( Fig. 74); secondary membranous lobe translucent, slender and cylindrical. Caudal filament translucent whitish. Female imago. Length (mm): body, 9.2; fore wing, 9.0; hind wing and cerci broken. Similar to male imago, except pigmentation more distinct and few other differences, as follows. Thorax. Pronotum shaded with gray, except pale transverse line between anterior and posterior portions, and pale longitudinal sublateral band; medial line concolorous with rest of notum. Mesonotum additionally shaded gray on anterior triangular mark (after mesonotal protuberance). Middle and hind legs shaded more slightly with gray. Wing membranes yellowish. Abdomen ventrally shaded only submedially and laterally on sterna VII–IX; sternum VIII with small anteromedian subquadrate socket ( Fig. 93). Caudal filaments translucent whitish (all except basal segment lost). Egg. Length, 250 µm; width, 200 µm. Yellowish with whitish polar cap. Polar cap relatively large (width 0.7× maximum width of egg).   Etymology.We are pleased to name this species after Sueli Pereira, a mayfly specialist who kindly provided material treated in this work.   Distribution( Fig. 179). Brazil( Goiás), Surinam.   Diagnosis.  Campsurus pereirae  sp. nov.is known from adults of both sexes, and it can be distinguished from other species of  Campsurusby: 1) posterior margin of male abdominal sternum IX truncate ( Fig. 71); 2) pedestal of each side touching basally, with apically acute parastylus ( Fig. 72), round inner corner strongly projected; 3) base of main lobe of penes sclerotized, strongly expanded laterally and proximally with its dorsal surface finely granulated ( Fig. 73), apical 1/3 narrowing abruptly, rounded and slightly curved ventrally; secondary membranous lobe cylindrical and slender; 4) small size (length of male fore wings 6.5–7.0 mm); 5) female socket single, subquadrate ( Fig. 93); 6) egg with large polar cap, ratio maximum width of egg/width of PC =1.4.   Discussion.The extremely expanded penes and the fine granules present on them are unique to  C. pereirae  sp. nov., distinguishing this species from the closely related  C. cuyuniensis,  C. nessimiani  sp. nov.,  C. dasilvai  sp. nov.,  C. zunigae  sp. nov.and  C. janae  sp. nov.  Campsurus janae  sp. nov.also presents penes with an extremely wide base, but the penes are smooth, and the pedestals are much larger and shorter than in  C. pereirae  sp. nov.Again, the finely granulated penes are unique to  C. pereirae. 1585352604 2012-02-26 APM, CZNC Parque Nacional das Emas & LF Sgarbi & Santos, E Brazil -18.26111 21 -52.888336 20 321 2 2 Goias holotype 1585352610 1978-12-27 2012-02-24 1978-12-27 APM, CZNC, FAMU LF Sgarbi & Santos, E & Brokopondo & JG Peters Brazil 22514 5.0 Brokopondo district 1305 -54.983334 Mineiros 20 321 5 1 4 Goias