Apobaetis biancae sp. nov. Boldrini

(Figs 2 A–2J, 4A, 4B)

Apobaetis sp. nov. A in Boldrini & Cruz 2014: 4

Diagnosis. Larva. 1) labrum rectangular, distal margin without shallow medial emargination, medial area of distal margin with four robust pointed setae (Fig. 2A); 2) maxillary palp long, more than 2.5× the length of galea-lacinia, segment I slightly longer than galea-lacinia (Fig. 2D); 3) lingua subquadrate with one medial lobe (Fig. 2E); 4) glossa distally rounded; 5) inner projection of labial palp segment II rounded, segment III triangular (Fig. 2F); 6) tarsal claws 1.4× the length of tarsus, without row of denticles (Fig. 2G); 7) posterior margin of tergum IV with triangular spines (longer than wide) (Fig. 2H).

Description. Larva. Body: 4.0– 4.2 mm; cercus approximately 1.5 mm. Body whitish (Fig. 4 A–B). Head. Antenna with minute spines on the apex of each segment. Frontal keel absent. Labrum (Fig. 2A): rectangular; distal margin without shallow medial emargination and medial lobe; distolateral area and distal margin with robust setae; medial area of distal margin with four robust setae on dorsal surface; ventral surface with one row of thin setae on medial area near distal margin. Left mandible (Fig. 2B): outer and inner sets of incisors with 5 and 3 denticles, respectively; prostheca robust, bifid at apex, inner margin frayed at middle; margin between prostheca and mola concave, with frayed lobe close to subtriangular process; tuft of robust setae at base of mola present; subtriangular process wide; denticles of mola not constricted; lateral margin convex. Right mandible (Fig. 2C): outer and inner sets of incisors with 3 denticles each; prostheca slender, bifurcated at apex; margin between prostheca and mola concave; tuft of setae at base of mola absent; denticles of mola constricted; lateral margin convex. Maxilla (Fig. 2D): maxillary palp long, more than 2.5× the length of galea-lacinia; segment I slightly longer than galea-lacinia, segment II without distal constriction; maxillary palp with scarce, thin, simple setae scattered over the surface. Hypopharynx (Fig. 2E): lingua subquadrate and longer than superlingua, with one medial lobe and without distal tuft of setae; superlingua not expanded, with short, thin, simple setae scattered over distal margin. Labium (Fig 2F): glossa narrowing slightly distally with apex rounded, longer than paraglossa; dorsal surface with one arc of setae on distal half, from inner to outer margin; ventral surface covered with small robust setae (not completely illustrated). Paraglossa curved inward; dorsal surface with three robust setae on apex and with one longitudinal row of five robust setae near inner margin; outer margin with one row of 14 robust setae; ventral surface with one longitudinal row of five robust setae in the middle. Labial palp with segment I shorter than the length of segments II and III combined; inner projection of labial palp of segment II rounded and laterally directed, outer margin and projection covered with thin, long, simple setae; ventral surface of segment II with of thin, long setae near the outer margin; segment III triangular, covered with thin, long, simple setae on outer margin, dorsal surface with one row of nine robust setae, outer margin concave. Thorax. Foreleg (Fig. 2G). Femur: with one row of 14 short robust setae on dorsal margin. Tibia: ventrally with one row of four short robust setae. Patella-tibial suture from dorsal to ventral margin. Tarsus: ventrally with one row of 12 short robust setae. Tarsal claws 1.4× the length of tarsus, row of denticles absent. Abdomen. Terga II and VII with a reddish medial mark, tergum V with a reddish lateral mark, terga IX and X reddish. Tergal surface covered by scale-like triangular spines (Fig. 2H); posterior margin with triangular spines (longer than wide) (Fig. 2H). Gill VI (Fig. 2I) oblong. Paraproct (Fig. 2J) with four marginal spines, posterolateral extension without spines. Cerci and paracercus with lateral spines on all segments.

Comments. This species is found with low abundance on the sand bottom of a small stream.

Etymology. After Bianca M. P. O. Boldrini, friend, wife of second author (R.B.), a great teacher and a fellow scientist, who gives him all the support needed.

Material examined. Holotype, one larva in alcohol, Brazil, Rondônia, Colorado do Oeste, Rio Cabixi, S 13°15’31.8” / W060°20’04.8”, 06.ix.2012, Boldrini, R., Fernandes, A.S., Hamada, N., Nascimento, J.M.C. cols, INPA . Paratypes, same data as holotype, one larva in alcohol and two mounted on slides, UFRR .