Alisotrichia dilatata, Alves & Takiya & Santos, 2023

Alves, André Almeida, Takiya, Daniela Maeda & Santos, Allan Paulo Moreira, 2023, Five new species of Alisotrichia Flint, 1964 (Trichoptera: Hydroptilidae: Leucotrichiinae) from Northeastern Brazil, Revista Brasileira de Entomologia (e 20230073) 67, pp. 1-11 : 7

Alisotrichia dilatata sp. nov.

urn:lsid:zoobank.org:act:528B112C-6263-449B-90E1-9E50E15CCF7A ( Figs. 8 , 9 A-9E)

Alisotrichia sp. 2 in Takiya et al. (2016)

Description. Adult male. Length 1.41–1.72 mm (mean = 1.56 mm, SD = 0.07, n = 116). General color,in ethanol, light brown ( Fig. 8 ). Antennae 18-articulated; scape enlarged, almost elliptical, with anteroventral margin produced in anterior view ( Fig. 9E ); pedicel slightly globose, chalice-like, about the same length as that of the next two articles combined ( Fig. 9E ); flagellomeres short, covered by scale-like setae, apical article tapering ( Fig. 9E ). Ocelli 2. Maxillary palpi 5-articulated, 4th and 5th palpomeres thin, 5th palpomere about 1.5x longer than 4th. Labial palpi 3-articulated. Mesoscutellum with transverse suture. Metascutellum diamond-shaped. Tibial spurs formula 0,2,4, each pair of meso- and metatibial spurs with one spur about twice as long as the other. Fore- and hind wings with long dark brown setae ( Fig. 8 ). Abdominal segment VII without ventromesal process ( Fig. 9B, 9C ).

Male genitalia. Segment VIII with a pair of dorsolateral processes, posterad directed, each bearing an elongate, spine-like seta, extending beyond segment apex ( Figs.9A, 9C ); in lateral view, with rounded apex ( Fig. 9C ); in ventral view, posterior margin with a deep mesal Y-shaped and lateral narrow V-shaped incisions ( Fig. 9B ). Segment IX fused with segment X, reduced ventrally; with a pair of lateral slender, elongate processes, slightly curved upwards in lateral view, slightly curved inwardly in dorsal view ( Fig. 9A ); anterolateral margins with a pair of slender apodemes reaching segment V internally ( Figs. 9 A-9C). Segment X long, membranous; with lateral margins slightly arched in dorsal view, with apex slightly concave ( Fig. 9A ); dorsally with a pair of slender, sinuous sclerites, tapering to acute apices ( Fig. 9A ). Subgenital plate, in ventral view, long, reaching segment VII internally, with anterior portion produced into a pair of rods; posterior margin subrectangular, with a small subapical open area ( Fig. 9B ). Inferior appendages absent. Phallus tubular, long, with a mesal constriction followed by a dilatation, subapically constricted and covered by a very thin membrane; with a pair of apical lobes, each one with bifid apex, internally flattened and with a pointed projection. ( Fig. 9D ); ejaculatory duct projecting between apical lobes ( Fig. 9D ).

Taxonomic notes. This new species also belongs to the orophila group due to the presence of a pair of dorsolateral processes on segment VIII. Alisotrichia dilatata sp. nov. is more similar to A. kanukua Harris & Flint, 2002 and A. froehlichi sp. nov. by the segment X having slightly arched lateral margins, with slender sclerites, and segment VIII with rounded apex in lateral view and posterior margin bearing a median Y-shaped and a pair of V-shaped lateral incisions in ventral view. This new species can be distinguished from this and other Alisotrichia species by: (1) the dorsal sclerites on segment X sinuous ( Fig. 9A ); (2) the deeper mesal Y-shaped and a pair of shallow lateral V-shaped incisions on posterior margin of segment VIII in ventral view ( Fig. 9B ); and (3) the pair of long, slender, lateral processes of segment IX ( Fig.9E ). Furthermore, in A. dilatata sp. nov. the phallus aspect is peculiar, with apical portion almost elliptical in dorsal view, and the pair of bifid apical lobes are flattened apically and produced into a pointed projection ( Fig. 9D ).

Etymology: The species name is a reference to the apical portion of the phallus being expanded or dilated, from Latin, “dilatata ” (expanded).

Distribution: Brazil (Ceará, Mato Grosso do Sul). Caatinga and Cerrado biomes.

Material examined. Holotype male: BRAZIL: Ceará, Ubajara, Parque Nacional de Ubajara , Rio das Minas na altura do teleférico, 03°49’58”S, 40°53’53”W, 420 m, 20-27.iv.2012, Malaise trap, J.A.Rafael et al.leg.( CZMA).

Paratypes: same data as holotype, 21 males ( CZMA) , 22 males ( DZRJ) , 22 males ( MNRJ) , 22 males ( INPA) , 22 males ( UFBA) ; same data as holotype, but trilha Araticum, Rio das Minas, 03°50’03”S, 40°54’18”W, 524 m, 21-24.v.2012, Rafael et al. leg., 5 males ( CZMA) .

Additional material: BRAZIL: Mato Grosso do Sul, Costa Rica, Rio Sucuriú , 18°59’03”S, 53°10’0”W, 02.xi.2004, Light, O. Froehlich leg., 1 male ( UFBA)

Figures

Figure 8 Alisotrichia dilatata sp. nov. Paratype male (in alcohol), dorsal habitus. Scale bar = 0.5 mm.

Figure 9 Alisotrichia dilatata sp. nov. Male genitalia (holotype): A–D. (A) dorsal view; (B) ventral view; (C) lateral view; (D) phallus, dorsal view. (E) antenna, frontal view. Ab - breviation: lat. proc. = lateral process of segment IX.Scale bar = 0.1 mm.