Paracloeodes charrua Emmerich & Nieto, 2009

Lima, Lucas R. C., Cruz, Paulo Vilela & Pinheiro, Ulisses, 2013, The adult stage of Paracloeodes charrua Emmerich & Nieto, 2009 (Ephemeroptera: Baetidae), Zootaxa 3640 (4), pp. 597-600 : 597-599

Paracloeodes charrua Emmerich & Nieto, 2009

( Figs. 1–6 )

Diagnosis. The male imagos of P. cha rr ua can be distinguished from the other species of genus by the following combination of characters: (1) hind wings present; (2) tibia of foreleg almost twice the length of femur; (3) abdominal terga light brown, submedially with a pair of small red spots; (4) posterior margin of subgenital plate convex, posteriorly with a small projection.

Male imago

Maximal length. Body: 3.3–3.8 mm; cerci broken; forewing: 3.3–4.2 mm; hind wing: 0.54–0.8 mm; tibia I: 1.3 mm; tibia II: 0.8 mm; tibia III: 0.7 mm.

Head ( Figs. 1–2 ). Coloration brown; compound eyes blackish, turbinate portion light brown. Antenna with scape and pedicel light brown, flagellum lighter. Dorsal portion of turbinate eyes oval; length 1.8x width; stalk height 1.1x width of dorsal portion; inner margins not parallel, divergent anteriorly.

Thorax ( Figs. 1–2 ). Pronotum brown; mesonotum brown with medioparapsidal suture darker, sublateroscutum brown, posterior scutal protuberance brown; metanotum brown; prosternum brown. Anteronotal protuberance rounded. Legs yellowish with a blackish line on posterior face. Leg I: tibia 1.9× length of femur; tarsi 1.7× length of femur. Leg II tibia 1.4× length of femur; tarsi 0.5× length of femur. Leg III tibia 1.4× length of femur; tarsi 0.5× length of femur. Forewing ( Fig. 3 ): membrane hyaline, veins light yellow, stigmatic area with five cross veins, not touching subcostal vein. Marginal intercalary veins paired, except between veins ICu2 and A; length of forewing about 2.2× width. Hind wing hyaline with two complete longitudinal veins; costal process quadrangular located on basal third ( Figs. 4 a–4b).

Abdomen ( Figs. 1–2 ). Terga light brown, submedially with a pair of small red spots; segments VII–X darker and segments II–VI lighter. Tracheation black. Sterna yellowish, medially with two pairs of small red spots. Genitalia ( Fig. 5 ) with segments of forceps whitish, basally washed with brown. Forceps segment I cylindrical, without distomedial projection; 0.3× length of segment II; distance between base of forceps 0.4× distance between lateral margins of forceps. Forceps segment II narrow submedially. Forceps segment III elongate, length 2.9× the width; 0.2× length of segment II. Posterior margin of subgenital plate convex, posteriorly with a small projection ( Fig. 5 ).

Female imago

Maximal length. Body: 3.6–4.0 mm; cerci: broken; forewing: 3.4–3.8 mm; hind wing: 0.45–0.52 mm; tibia I: 0.6 mm; tibia II: 0.7 mm; tibia III: 0.6 mm.

Head ( Fig. 6 ). Coloration light brown; compound eyes blackish. Antenna with scape, pedicel and flagellum light brown.

Thorax ( Fig. 6 ). Pronotum light brown; mesonotum brown with medioparapsidal suture darker, sublateroscutum brown, posterior scutal protuberance brown; metanotum brown; prosternum brown. Anteronotal protuberance rounded. Leg I: tibia 1.2× length of femur; tarsi 0.4× length of femur. Leg II tibia 1.4× length of femur; tarsi 0.4× length of femur. Leg III tibia 1.2× length of femur; tarsi 0.4× length of femur. Forewing hyaline,veins light yellow, stigmatic area with five cross veins, two touching subcostal vein. Marginal intercalary veins paired, except between veins MP2 and ICu2; length of forewing about 2.6× width. Hind wing hyaline with two complete longitudinal veins; costal process quadrangular located on basal third.

Abdomen ( Fig. 6 ). Terga light brown, submedially with a pair of small reddish spots. Tracheation black. Sterna yellowish, medially with two pairs of small reddish spots.

Material examined. BRAZIL, Pernambuco State, Amaraji, Rio Amaraji, 8°21'48.9"S, 35°28'49.0"W, 20/i/ 2011, 320m, Lima L.R.C., Nicacio G. cols, three male imagos (light trap) (UFPE); same data as preceding except 21/iv/2012, one male imago (CZNC); BRAZIL, Pernambuco State, Amaraji, Poço do Carreiro, 8°22'1.94"S, 35°28'8.73"W, 28/iv/ 2012, 269m, Lima L.R.C. coll., one male imago, (light trap) (INPA); BRAZIL, Pernambuco State, Jaqueira, Rio Pirangi, 8°44'53.0"S, 35°48'51.1"W, 23/v/ 2012, 189m, Lima L.R.C. coll., two male imagos (INPA); same data as preceding except 13/vii/2012, two male imagos (reared) (CZNC); BRAZIL, Pernambuco State, Ribeirão, Rio Amaraji, 8°26'34.1"S, 35°24'22.1"W, 21/i/ 2011, 124m, Lima LRC, Nicacio G. cols., one female imago (UFPE); BRAZIL, Pernambuco State, Flores, Rio Pajeú, 7°52'35.7"S, 38°00'04.0"W, 19/vii/ 2011, 473m, Lima LRC coll., two female imagos (reared) (1 INPA, 1 UFPE).

Comments. The male imago of P. charrua can be distinguished from other male imagos described by: the ratio of tibia/femur of foreleg which is almost twice longer in P. charrua than in P. minutus and P. portoricensis (about 1.4x); the abdominal color pattern; the presence of hind wings; and one conspicuous characteristic, the presence of a small pointed projection on the posterior margin of the subgenital plate ( Fig. 5 ). This projection is for the first time reported to the genus, since it is not present in male imagos of P. minutus and P. portoricensis . Although uncommon, a similar projection has also been reported for male adults of Rivudiva minantenna Lugo-Ortiz and McCafferty, 1998 , and because of that, two species described based only on adults were transferred to this genus: Rivudiva coveloae (Traver, 1971) and R. venezuelensis (Traver, 1943) (Salles & Nascimento, 2011) . Other similarities occurs between the subgenital plates of P. portoricensis and the recently described male imago of Rivudiva trichobasis Lugo-Ortiz & McCafferty, 1998 (Cruz et al. 2011) : both possess the subgenital plate concave, though much deeper in R. trichobasis than in P. portoricensis . Given the few number of species described based on nymphs and adults, it is difficult to ascertain at this time if these similarities are an example of convergence or an indicative of close relationship between both genera.

Figures

FIGURES 1 – 6. Adults of Paracloeodes charrua. Emmerich & Nieto, 2009. 1, male imago (dorsal view). 2, male imago (lateral view). 3, forewing. 4 a, hind wing. 4 b, hind wing (enlarged). 5, genitalia. 6, female imago (dorsal view) (SP = small projection).