Camelobaetidius cayumba ( Traver & Edmunds, 1968 )

Lima, Lucas R. C., Boldrini, Rafael & Pinheiro, Ulisses, 2012, Imagos of Camelobaetidius cayumba (Traver & Edmunds, 1968) (Ephemeroptera: Baetidae), Zootaxa 3401, pp. 63-65 : 63-65

Camelobaetidius cayumba ( Traver & Edmunds, 1968)

( Figs. 1–7 )

Diagnoses. Male: (1) anteronotal and metascutellar protuberance rounded ( Fig. 2 ); (2) terga of abdominal segments II–III and VI medially with remarkable dark marks, segment II with subrectangular mark, segment III with W-shaped mark, and segment VI with spots without form ( Fig. 1 ); (3) forceps segment I without distomedial projection; (4) posterior margin of subgenital plate convex, posteriorly projected ( Fig. 3 ). Female: (1) anteronotal and metascutellar protuberance rounded; and (2) abdominal terga with segments I–II and V medially with dark spots without form ( Fig. 4 ).

Male imago. Body: 4.0– 4.5 mm; cerci broken; forewing: 4.1–4.2 mm; hind wing: 0.8 mm; tibia I: 1.4 mm; tibia II: 1.0 mm; tibia III: 0.8–0.9 mm (n=2).

Head ( Figs. 1, 2 ). Coloration brown; compound eyes yellowish black, turbinate portion reddish. Antenna with scape and pedicel light brown, flagellum light yellow.

Thorax ( Figs. 1, 2 ). Pronotum dark brown; mesonotum brown with medioparapsidal suture darker, sublateroscutum light brown, posterior scutal protuberance dark brown; metanotum dark brown; prosternum whitish. Anteronotal protuberance rounded. Metascutellar protuberance rounded. Legs. Yellowish. Tarsi segments II of middle and hind legs with a small apical spine ( Fig. 3 ). Leg I: tibia 2.1× length of femur; tarsi 1.3× length of femur. Leg II tibia 1.4× length of femur; tarsi 0.2× length of femur. Leg III tibia 1.5× length of femur; tarsi 0.2× length of femur. Forewing membrane hyaline; veins light brown; stigmatic area with four cross veins not touching subcostal vein; marginal intercalary veins paired, except between veins ICu2 and A; length of forewing about 2.6× width. Hind wing membrane and veins hyaline with two complete longitudinal veins; costal process pointed, located on basal third.

Abdomen ( Fig. 1 ). Terga light brown; segments II–III and VI medially with remarkable dark marks, segment II with a subrectangular mark, segment III with a mark in W-shaped, and segment VI with spots without form; and segments IV–V lighter. Tracheation black. Sterna yellowish, with segments VII–IX whitish. Caudal filaments white washed with brown. Genitalia ( Fig. 4 ). Segments of forceps whitish washed with brown. Forceps segment I without distomedial projection; 0.2×length of segment II; distance between internal margins of forceps 0.6× distance between lateral margins of forceps. Forceps segment II narrow submedially. Forceps segment III elongate, 4.2× as long as wide; 0.2× length of segment II. Posterior margin of subgenital plate convex, posteriorly projected.

Female imago. Body: 4.0– 4.5 mm; cerci: 6.4 mm; forewing: 4.8 mm; hind wing: 0.7 mm; tibia I: 1.0 mm; tibia II: 0.9–1.1 mm; tibia III: 0.8–0.9 mm (n=2).

Head ( Fig. 5 ). Antenna with scape, pedicel and flagellum light brown.

Thorax ( Fig. 5 ). Pronotum brown (lighter than male); mesonotum brown with margin of medioparapsidal suture darker, sublateroscutum brown, posterior scutal protuberance whitish; metanotum brown; prosternum whitish. Leg I: tibia 1.5× length of femur; tarsi 0.5× length of femur. Leg II tibia 2.0× length of femur; tarsi 0.4× length of femur. Leg III tibia 0.5× length of femur; tarsi 0.3× length of femur. Forewing ( Fig. 6 ), stigmatic area with five cross veins not touching subcostal vein; length of each intercalary vein 0.5× distance between adjacent longitudinal veins; length of forewing about 2.5× width. Hind wing ( Figs. 7 a, 7b).

Abdomen ( Fig. 5 ). Terga orangish brown, segments I–II and V medially with dark spots, without form. Sterna yellowish, with segments VII–IX whitish.

Material examined. Four female imagos (reared), BRAZIL, Pernambuco State, Recife, Rio Capibaribe, 8°02'47.4"S, 34°59'41.9"W, 10/viii/2011, Lima LRC, Souza WRM cols. (2 UFPE, 1 CZNC and 1 INPA); two male imagos, same data except 15/ix/2011 (1 INPA, 1 CZNC).

Comments. The shape of the anteronotal protuberance has been regarded as an important character in the genus Camelobaetidius ( Salles & Dias, 2004; Boldrini et al., 2010; Kluge & Novikova, 2011). Unlike many other Baetidae , the anteronotal protuberance in this genus is pointed, as stated at least for C. billi Thomas & Dominique, 2001 and C. francischettii Salles, Andrade & Da-Silva, 2005 ( Salles & Dias, 2004; Boldrini et al., 2010). In C. cayumba , however, the anteronotal protuberance is not as developed and pointed as in these species. Eight other species of the genus were described in the adult stage, but this characteristic has not been addressed in any of these descriptions. Because of this variation, it becomes necessary to evaluate these characters in a broader sense among species of the genus.

Figures

FIGURES 1 – 7. Adults of Camelobaetidius cayumba (Traver & Edmunds, 1968). 1 – 4, male imago. 5 – 7, female imago. 1, body (dorsal view). 2, body (lateral view). 3, tarsi. 4, genitalia (ventral view). 5, body (dorsolateral view). 6, forewing. 7 a, hind wing. 7 b, hind wing enlarged (AP: Anteronotal protuberance).