Itauara tusci Robertson & Holzenthal

Robertson, Desiree R. & Holzenthal, Ralph W., 2011, Revision of the Neotropical caddisfly genus Itauara Mueller, 1888 (Trichoptera, Glossosomatidae), ZooKeys 114, pp. 41-100 : 73-75

Itauara tusci Robertson & Holzenthal sp. n. Fig. 24 A–C

Description.

This species is very similar to Itaura rodmani sp. n., which also has very long, upturned, tusk-like parameres and a strongly upturned phallicata. The 2 species are separated based on the shape of the phallicata process, which is pointed and blade-like in Itaura tusci and rounded or blunt in Itaura rodmani . The phallicata of Itaura tusci is more lightly sclerotized than Itaura rodmani , especially at the distal portion. Additionally, in Itaura tusci , the dorsomesal margin of tergum X is irregular, with several small setose processes, whereas in Itaura rodmani , the dorsomesal margin is rather smooth and triangular. The ventrolateral processes of the 2 species also differ: Itaura tusci has a small upper and more elongate lower process; Itaura rodmani has a single, short, digitate process. Itauara blahniki also has upturned, tusk-like parameres, but is easily distinguished from Itaura tusci based on differences in tergum X and the phallicata.

Adult. Body, wings, and appendages pale or tawny brown, often intermingled with rufous or golden hairs, tibia and tarsi tawny brown. Wings with conspicuous white spot at the arculus. Forewing slightly broader past anastomosis, but with margins nearly parallel, apex rounded. Forewing venation incomplete, with apical forks I, II, and III present; Sc and R1 distinct along their entire lengths; fork I sessile; fork II petiolate, stem shorter than fork; fork III petiolate, stem about the same length as fork; Cu1 complete, reaching wing margin; Cu1 and Cu2 intersecting near anastomosis; row of erect setae present along Cu2; A3 absent; crossveins forming a relatively linear transverse cord; discoidal cell longer than Rs vein. Hind wing margins nearly parallel, tapering only slightly past anastomosis; apical forks II, III, and V present; Sc and R1 fused basally; A2 absent. Tibial spurs 1,4,4, foretibial spur extremely reduced and hairlike. Sixth sternal process thumb-like, apex attenuate and pointed, associated with weak oblique apodeme posteriorly.

Male genitalia. Preanal and inferior appendages absent. Segment IX dorsally narrow, broad medially and ventrally; anterior margin rounded; posterolateral margin membranous or very lightly sclerotized; sternum IX without modification. Tergum X incompletely fused to tergum IX with membrane or lightly sclerotized region ventrolaterally; dorsomesal margin slightly produced with several small irregular setose processes; dorsolateral margin with paired small, slightly down-turned, setose process; ventrolateral margin with 2 pairs of processes, the upper a small lobe-like process, the lower an elongate finger-like process bearing a few setae. Parameres present, paired, arising ventrobasally from fused endotheca and phallobase, sclerotized and rod-like, tusk-like, strongly curving upward, apex pointed. Phallobase reduced, lightly sclerotized with phallic shield. Phallicata forming a long lightly sclerotized dorsal sheath extending from phallobase, rugous distally, strongly curving upward with apex directed anterodorsally, with pair of broad, sclerotized blade-like lateral flanges, apex pointed and directed posteriorly. Endophallus membranous, enlarged and convoluted when invaginated, with 1 upper and 1 lower lobe.

Material examined.

Holotype male: BRAZIL: Rio de Janeiro: Rio das Flores, Macaé de Cima, 10 km SE Mury, 1000 m, 9.iii.2002 (Holzenthal, Blahnik, Paprocki, Prather) (UMSP000070932) (MZUSP).

Paratypes: BRAZIL: Rio de Janeiro: same data as holotype - 4 males, 26 females (UMSP); Rio Macaé, Macaé de Cima, 22°23'41"S, 042°30'08"W, 1000 m, 8.iii.2002 (Holzenthal, Blahnik, Paprocki, Prather) - 2 males, 10 females (UMSP); Encontro dos Rios ( Macaé /Bonito), 6 km S Lumiar, 22°23'29"S, 042°18'42"W, 600 m, 10.iii.2002 (Holzenthal, Blahnik, Paprocki, Prather) - 64 males, 145 females (MZUSP, UMSP).

Etymology.

The name tusci is derived from the Old English word for tusk, and refers to the extremely long parameres of this species.