3.2. 10. Triplectides ultimus Holzenthal, 1988

Figure 27

Material examined.

BRAZIL • 1 ♂; Minas Gerais, Itamonte, Parque Nacional de Itatiaia, Fazenda Cabeceira do Aiuruoca, Rio Aiuruoca; 22°20′57.93″S 44°41′37.60″W; 24 Nov. 2011; J. L. Nessimian leg.; [DNA voucher ENT 740]; DZRJ TRICHOPTERA 9182 . • 1 larva; Minas Gerais, Itamonte, Parque Nacional de Itatiaia, Córrego do Brejo da Lapa; 22°21’41.83”S 44°42′26.19”W; alt. 2,242 m; 07 Nov. 2011; A. L. H. Oliveira leg.; [DNA voucher ENT 2314]; DZRJ TRICHOPTERA 9183 • 1 ♂; Rio de Janeiro, Resende, Parque Nacional de Itatiaia, Abrigo Massena; 22°24′29.80″S 44°39′04.50″W; alt. 2,210 m; 26 Oct. 2013; light trap; J. L. Nessimian leg.; [DNA voucher ENT 3718]; DZRJ TRICHOPTERA 9184 .

Description.

Adult. For a full description of male and female adults of T. ultimus see Holzenthal (1988). — Larva. Length up to 15 mm (n = 1) (Fig. 27 A). Head: Anterior region of the head brown to golden brown (in alcohol), with a pale oval area around the stemmata (Fig. 27 B); almost rectangular, slightly enlarged posteriorly; many pale muscle scars on posterior portion of the head (Fig. 27 B). Labrum brown, subtrapezoidal, with 3 pairs of long setae. Mandibles asymmetrical, dark, typical for Triplectides (right mandible with 6 teeth around a concavity and left mandible with 5 teeth). Submentum subrectangular. Ventral apotome subtriangular, widened anteriorly, slightly constricted at mid-length, and narrowing at posterior portion to an acute tip (Fig. 27 B). — Thorax: Pronotum, mesonotum, and legs, yellowish brown (Fig. 27 D). Pronotum with muscle scars pale (Fig. 27 D); anterior margin crenulate, lateral margin slightly produced and pointed (Fig. 27 C, D). Mesonotum very pale, almost covered by a pair of large sclerites: sa 1 each with single seta; sa 2 each with 3 setae (2 very long mesal setae and 1 posterior very short); sa 3 each with 6 setae (3 anterior setae, 2 very long mesal and 1 posterior short). Metanotum covered by 5 sclerites: sa 1 pair, subquadrate, bearing each a single seta, sa 2 seems fused, forming one sclerite, weakly sclerotized, with pair of long setae, sa 3 sclerites elongate, oval, bearing each with 4 setae (1 very long and others short) (Fig. 27 D). Prosternum subtrapezoidal. Mesosternum with a pair of sclerites subtriangular curved laterally. Metasternum bearing about 12 setae (Fig. 27 E). Foretrochantin sinuous with anterodorsal margin slightly curved, narrowed at the tip and upturned, and anteroventral margin almost straight (Fig. 27 C). Legs yellowish brown and setose (Fig. 27 G). — Abdomen: Gills simple, present on segments II – VIII: segments II – VII with dorsal, lateral, and ventral filaments; segment VIII with ventral filaments (Fig. 27 H). Segment I-II with a pair of small setae in posterior portion; segments III – VIII with lateral fringes. Segment VIII with a pair of long posteromesal setae. Segment IX dorsal sclerite with 6 long setae on its posterior margin, and 2 pairs of very short setae behind those, and one anterolateral short seta at each side of the sclerite (Fig. 27 F). Anal claws single, large and, acute, with a small dorsal accessory hook (Fig. 27 F). — Larval case: Length up to 26 mm. A hollow stick with several small sticks glued close to the opening (Fig. 27 I). — Pupa unknown.

Distribution.

Brazil (Minas Gerais and Rio de Janeiro states).

Habitat.

Specimens were collected in streams of different orders with crystalline and alkaline waters at high altitudes in the Atlantic Forest, mainly in the Serra da Mantiqueira region.

Remarks.

In general, the larva of T. ultimus is very similar to other Triplectides larvae showing the head and body sclerites brown to golden brown, with head rectangular and enlarged at posterior area. The main characters to identify larvae of this species are the narrow ventral apotome, subtriangular with anterior portion slightly widened and narrower in posterior portion, with a pointed tip; pronotum with muscle scars pale and anterior margin crenulate with lateral margin slightly produced and pointed; metanotum covered by 5 sclerites: sa 1 pair, subquadrate, bearing each a single seta, sa 2 seems fused in only one sclerite, weakly sclerotized, and sa 3 sclerites elongate, and oval,; metasternum bearing about 12 setae; foretrochantin sinuate with anterodorsal margin slightly curved, narrowed at tip, and upturned and anteroventral margin almost straight; and abdominal gills present on segments II – VIII: II – VII with dorsal, lateral, and ventral filaments and VIII with ventral filaments only.