Oxyethira (Tanytrichia) septentrionalis, De Souza, Wagner Rafael M. & Santos, Allan Paulo Moreira, 2017

De Souza, Wagner Rafael M. & Santos, Allan Paulo Moreira, 2017, Taxonomic study of the genus Oxyethira Eaton 1873 (Trichoptera: Hydroptilidae) from Northeast Brazil: Eleven new species and distributional records, Zootaxa 4236 (3), pp. 484-506 : 498

Oxyethira (Tanytrichia) septentrionalis sp. nov.

Fig. 9A–9 D

Oxyethira sp. 1 Takiya et al. 2016: 170

Description. Holotype. Length 2.0 mm. General color pale brown (in alcohol). General pattern of Neotropical Oxyethira . Sternum VII with small posterior mesoventral process ( Figs. 9A, 9 C).

Male genitalia: Segment VIII annular, covered with setae; sternum VIII with U-shaped posteromesal incision ( Fig. 9A ); tergum VIII excavated medially, excavation partially enclosed with two mesolateral lobes with long setae ( Fig. 9 B). Segment IX retracted in segment VIII, sternum IX produced anteriorly into anterior area of segment VI, with anterior margin rounded, nearly truncate ( Figs. 9A, 9 B); in lateral view, produced dorsad near posterior end. Inferior appendages short and square, with darkened apices; fused to sternum IX and to each other basally ( Fig. 9A ); in lateral view, hidden by segment VIII. Subgenital plate inconspicuous; in ventral, dorsal, and lateral views covered by segment VIII ( Figs. 9A, 9 B, 9C); in lateral view curved posterodorsad, slender, shorter than inferior appendages ( Fig. 9 C). Bilobed process with short processes, each with small apical seta ( Figs. 9A, 9 C). Tergum X membranous. Phallus divided into basal and distal portions; basal portion tubular, longer than distal portion; distal portion sclerotized on right side, sclerotization subtriangular, with elongate spine-like process arising at mid-length of left side; ejaculatory duct not protruding ( Fig. 9 D).

Remarks. This species is placed in the subgenus Tanytrichia due to segment IX reaching segment IV. However, the short, fused inferior appendages and the general aspect of the segment IX is more similar to the Loxotrichia species. Oxyethira septentrionalis sp. nov. is most similar to O. sencilla Holzenthal & Harris 1992 , both having tergum VIII excavated and forming two mesolateral lobes, short inferior appendages, and the subgenital plate inconspicuous and covered by segment VIII. The new species can be distinguished by the phallus being divided into basal and distal portions, with the distal portion having a long spine-like curved process at midlength.

Etymology. The specific name is a reference to the type-locality, one of the most northern region of Brazil. The word septentrionalis is a Latin adjective meaning “northern”.

Material examined. Holotype. BRAZIL: Piauí: Piracuruca, Parque Nacional de Sete Cidades , alojamento, 4°05'57''S, 41°42'34''W, 193 m, 20.vi.2012, DM Takiya col., light trap, 1 ♂ ( CZMA) . Paratypes. Same data as holotype, 1 ♂, (CZMA). Same data as holotype except by, Poço da Bananeira , 4°05'56''S, 41°40'34''W, 189 m, 19.iv.2012, 1 ♂ ( DZRJ) . Same data as holotype except cachoeira do Riachão , 4°06'58''S, 41°40'13''W, 171 m, 18.iv.2012, 13 ♂ ( DZRJ) .

Figures

FIGURE 9 A – 9 D. Oxyethira septentrionalis sp. nov. Male genitalia: 9 A, ventral; 9 B, dorsal; 9 C, left lateral; 9 D, phallus, dorsal.