Mortoniella truncata, Blahnik & Holzenthal, 2011

Blahnik, Roger J. & Holzenthal, Ralph W., 2011, Revision of the austral South American species of Mortoniella (Trichoptera: Glossosomatidae: Protoptilinae) 2851, Zootaxa 2851 (1), pp. 1-75 : 34

Mortoniella truncata , new species

Fig. 16

Mortoniella truncata is most closely related to M. asymmetris , n. sp. Both species are characterized by having paramere appendages asymmetrically developed and differing in length, the left one shorter than the right. Other character similarities include upright processes bordering the paramere appendages than emerge near the ventral margin of the phallicata, and mesal pocket-like structures of the inferior appendages with very elongate, sinuous, spine-like apical processes which appear to be fused or semi-fused mesally. Mortoniella truncata is most easily and diagnostically distinguished from M. asymmetris by having a tergum X with truncate, rather than acute, apicolateral projections. As discussed in the diagnosis for M. asymmetris , both of these species seem to be closely related to the group of species discussed under M. unota , agreeing in having a dorsal phallic spine that is sharply upturned apically, with a slight, but distinct, ventral deflection at the point of inflection, and with the spine, in dorsal view, distinctly widened at the inflection point and narrow apically.

Adult. Length of forewing: male 2.2–2.4 mm, female 2.3–2.5 mm. Forewing with forks I, II, and III present, hind wing with fork II only. Spur formula 0:3:4. Overall color, in alcohol, medium brown. Legs brown, apices of tarsi whitish, tibial spurs somewhat darker than legs, but not strongly contrasting in color. Wing bar at anastamosis indistinct (in alcohol), marked with whitish setae on anal margin.

Male genitalia. Ventral process of segment VI laterally compressed, somewhat posteriorly directed, subtriangular, wide basally, acute apically. Segment IX nearly evenly rounded anterolaterally, length greatest midlaterally, posterolateral margin weakly, convexly rounded, narrowing ventrally; segment deeply excised dorsomesally and ventromesally, forming lateral lobes, lobes separated dorsomesally by much less than 1/2 width of segment. Tergum X with narrow, U-shaped mesal excision, extending about 1/2 length of segment, and projecting lateral lobes; lateral lobes with apices broadly truncate as viewed dorsally, subacute as viewed laterally. Inferior appendages without ventromesal projection; laterally, on each side, with setose, tapering, dorsally-directed lobes. Mesal pockets of fused inferior appendages with apical processes moderately elongate, sinuous, more or less fused mesally. Paramere appendages uniformly narrow, asymmetrically developed in length and orientation, the left short and downturned, the right long and nearly straight. Dorsal phallic spine, as viewed laterally, sharply upturned in apical 1/3rd, with distinct sinuous deflection on ventral margin at point of upturn; in dorsal view, very distinctly widened in middle, apical part abruptly narrowed, apex acute. Phallicata with weakly sclerotized dorsomesal process and paired, upturned, lightly sclerotized processes arising from basoventral margin; laterally with asymmetrical, lightly sclerotized areas, paralleling paramere appendages. Endophallic membrane somewhat globular in shape, simple in structure, without apparent ventromesal spine; phallotremal spines absent.

Holotype male: BRAZIL: Minas Gerais: spring trib to Rio Macauba, near Pandeiros , 15°28'38"S, 044°44'38"W, 525 m, 17.xi.2001, Paprocki & Blahnik ( UMSP000208501 ) (alcohol) ( MZUSP).

Paratypes: BRAZIL: Minas Gerais: same locality and date as holotype — 3 males, 17 females (alcohol) ( UMSP) .

Etymology. This species is named M. truncata for the truncate apices of tergum X of the male.

Figures

FIGURE 16. Mortoniella truncata, new species, male genitalia: A—lateral; B—segment IX and tergum X, dorsal; C—phallic ensemble, ventral; D—dorsal phallic spine, dorsal.