Paracloeodes atroari, Nieto, Carolina & Salles, Frederico Falcaõ, 2006

Nieto, Carolina & Salles, Frederico Falcaõ, 2006, Revision of the Genus Paracloeodes (Ephemeroptera: Baetidae) in South America, Zootaxa 1303, pp. 1-33 : 8-9

Paracloeodes atroari sp. n. ( Figs. 12–22 )

Mature nymph ( Fig. 12 ). Length: body, 2.8–2.9 mm; cerci and terminal filament broken. Antennae partially broken. Head whitish, except for light brown mark between ocelli. Turbinate portion of male compound eyes light orange­brown. Frontal keel present, ocelli yellowish­brown. Antennae whitish. Mouthparts: labrum ( Fig. 13 ), dorsally with a pair of subapical setae near middle. Left mandible with external margin convex, prostheca with 2 denticles ( Fig. 14 ). Right mandible with external margin straight ( Fig. 15 ). Lingua scarcely shorter than superlingua and rounded apically. Maxillae with palpi 2.2 times the length of galea­lacinia ( Fig. 16 ). Labium ( Figs. 17 a–b) with segment II of palpi with rounded distomedial projection, 2.3 times width of segment III, segment III conical.

Thorax dark brown, mesonotum with three median whitish spots along midline. Pleura dark brown, sterna whitish. Legs ( Fig. 18 ) whitish, femora tinged with light brown, tarsal claws 0.5 times the length of tarsi, with 2 rows of denticles, small basally, increasing in size distally ( Fig. 19 ). Hind wing pads absent.

Abdomen light brown, terga I, and VIII–X whitish suffused with brown, terga II–VII entirely brown, except for two posterolateral whitish spots on segments II and IV ( Fig. 12 ). Posterior margin of terga with spines 1.5 times wider than long ( Fig. 20 ). Sterna whitish, including paraprocts. Gills whitish with external margin sclerotized, elongate, apically pointed, with main branch of trachea poorly pigmented ( Fig. 21 ). Paraprocts with 12 spines apically ( Fig. 22 ).

Adults. Unknown.

Etymology. Atroari is the name of one of the indigenous tribes that inhabit the area where the species was collected.

D iscussion. This species can be distinguished from the other species of the genus by the following combination of characters, 1) frontal keel present; 2) labrum with a pair of subapical setae near middle ( Fig. 13 ); 3) labium with segment II of palpi with rounded distomedial projection, 2.3 times the width of segment III ( Fig. 17 b); 4) tarsal claws long, 0.5 times the length of tarsi ( Fig. 18 ); 5) hind wing pads absent; 6) posterior margin of abdominal terga with spines 1.5 times wider than long ( Fig. 20 ); 7) gills with main branch of trachea poorly pigmented ( Fig. 21 ); 8) paraprocts with 12 spines apically ( Fig. 22 ).

Material. Holotype, male nymph, BRAZIL, Amazonas State, Presidente Figueiredo, Sossego da. Pantera, km 20, folhiço de fundo, remanso, 7/ X/ 2003, Salles col. Paratypes: 3 nymphs same data. Holotype and 2 paratypes housed at INPA. Other paratype deposited at IFML.

Figures

FIGURE 12 – 22. Paracloeodes atroari sp. n. Nymph. 12, General view. Mouthparts (Figs. 13 – 17): 13, labrum, d. v.; 14, left mandible v. v.; 15, right mandible v. v.; 16, maxilla v. v.; 17 a, labium, left d. v., right v. v.; 17 b, palp: segments II – III. 18, leg I; 19, tarsal claw I. 20, posterior margin of tergum IV. 21, gill IV. 22, paraproct.