Mortoniella (Nanotrichia) triangularis, Blahnik & Holzenthal, 2017

Blahnik, Roger J. & Holzenthal, Ralph W., 2017, Revision of the northern South American species of Mortoniella Ulmer 1906 (Trichoptera: Glossosomatidae: Protoptilinae) *, Insecta Mundi 2017 (602), pp. 1-251 : 102

Mortoniella (Nanotrichia) triangularis , new species

Fig. 87

This species is easily diagnosed by the shape of the dorsal phallic spine, which is trianguloid in lateral view, widening from the base to the apex, with apical spines on the dorsal and ventral margins. Like M. quadridactyla , n. sp., which is probably the most closely related species, the spine is deeply cleft mesally. In the case of M. triangularis , the cleft extends almost to the base of the spine.

Adult—Length of forewing: male 2.0 mm; female 2.2-2.3 mm. Forewing with forks I, II, and III present, fork II with long stalk, hind wing with fork II only; both wings narrow, acute apically. Spur formula 0:3:4. Overall color medium brown, legs slightly paler. Tibial spurs short, slightly darker than legs, weakly contrasting in color. Forewing with white wing bar at anastomosis (evident in some specimens). Forewings of male with scale-like setae paralleling major veins (except apically).

Male genitalia —Ventral process of segment VI posteriorly projecting, narrow basally, length about 3 times width at base, apex subacute. Segment IX with anterolateral margin rounded and slightly produced in ventral ½, posterolateral margin nearly straight; segment deeply mesally excised dorsally and ventrally, forming lateral lobes, separated dorsomesally by less than ½ width of segment. Tergum X moderately elongate, lateral margins slightly converging from base; apex of tergum with U-shaped emargination, extending less than ½ length of tergum; apicolateral lobes simple, with small angulate projection; tergum, in lateral view, with subtruncate apex and broadly rounded basal ventrolateral lobe. Inferior appendages with small setose dorsolateral projections, apices acute and posteriorly directed. Mesal pockets of inferior appendage with elongate, narrow, posteriorly-directed, spine-like, apicoventral projections, apparently fused to ventral margin of phallicata basally. Paramere appendage elongate, narrow, apex acute, strongly and nearly evenly curved, apex dorsally directed, extending about same length as dorsal phallic spine. Phallobase with short ventral rod-like projections. Dorsal phallic spine, as viewed laterally, subtriangular in shape, narrow basally, very wide apically, with apical spine-like projections from dorsal and ventral margins, and additional spine on dorsal margin at about midlength; as viewed dorsally, with deep mesal incision, extending almost entire length of spine, spine-like projections from ventral margin projecting laterally, dorsal spines posteriorly projecting. Phallicata relatively lightly sclerotized, simple in structur-e. Endophallic membrane somewhat inflated, with large, lightly sclerotized, dorsal lobes; phallotremal spines absent.

Holotype male (alcohol)— ECUADOR: Zamora-Chinchipe: Zamora, 31.v.1976, A Langley , et al. ( NMNH) ( UMSP000095073 ).

Paratypes — ECUADOR: Zamora-Chinchipe: Zamora, 4.xii.1978, J Anderson– 2 males, 4 females (alcohol) ( NMNH).

Etymology —This species is named M. triangularis for the shape of the dorsal phallic spine of the male, which is distinctly trianguloid in appearance, as viewed laterally.

Figures

Figure 87. Mortoniella (Nanotrichia) triangularis, new species, male genitalia. A—lateral; B—segment IX and tergum X, dorsal; C—phallic ensemble, ventral; D—dorsal phallic spine, dorsal; E—ventral process of segment VI, lateral.