Mortoniella (Mortoniella) apiculata Flint, 1963

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 : 15-16

Mortoniella (Mortoniella) apiculata Flint, 1963

Fig. 2

Mortoniella apiculata Flint 1963: 466 ; Knutson and Flint 1971: 316 [ Empididae predators in pupal cocoons]; Sykora 1999: 386 [member of bilineata subgroup]; Blahnik and Holzenthal 2008: 70 [member of bilineata group].

This species is easily diagnosed from all other species in the bilineata group by the distinctively shaped apex of the dorsal phallic spine of the male, which is compressed (flattened on the median plane), but enlarged and rounded, as viewed laterally.

Adult —Length of forewing: male 5.0 mm. Forewing with forks I, II, and III present, hind wing with forks II, III, and V. Spur formula 0:4:4. Overall color medium golden or tawny brown. Tibial spurs darker, contrasting with legs. Wing without distinct bar at anastamosis.

Male genitalia —Ventral process of segment VI posteriorly projecting, very short, narrow basally, length only slightly greater than width at base. Tergum VIII distinctly elongate dorsally, membranous connection to tergum IX only moderately developed. Segment IX with anterolateral margin rounded and produced in ventral half, posterolateral margin with rounded (subangular) projection in dorsal half; segment deeply mesally excised dorsally and ventrally, forming lateral lobes, separated dorsomesally by more than ½ width of segment. Tergum X elongate, lateral margins rounded, laterally with subacute lateral lobes, each with prominent apical seta; apex of tergum distinctly sclerotized, subtruncate, with ventrolateral margins incurved and converging mesally to form linear “seam,” apicodorsally with lightly sclerotized connection (mesal notch absent); tergum ventromesally with paired rounded, lightly sclerotized ventromesal lobes in basal half, each with short setae. Inferior appendages with short rounded dorsolateral lobes and paired linear, apically tapering, ventromesal lobes. Mesal pockets of inferior appendage with relatively short, spine-like, posteriorly-directed, apicoventral projections. Paramere appendage short, linear, nearly uniform in width, apex acute. Phallobase with evident rounded, laterally compressed, dorsomesal apodeme. Dorsal phallic spine, as viewed laterally, with undulate contour, strongly curved basally, articulating with fused basal segments of paramere appendages, ventral margin only slightly produced and rounded in middle (not angulate), nearly rectilinearly upturned in apical third, apex distinctly enlarged and rounded, slightly recurved (shape somewhat variable, flattened and compressed as viewed dorsally). Phallicata without apparent basodorsal projection, ventrally with paired, lightly sclerotized, ventral lobes; ventral lobes, as viewed ventrally, moderately elongate, broad, rounded apically. Endophallic membrane simple in structure, with only weakly developed membranous lateral lobes; phallotremal spines absent.

Material examine d— ECUADOR: Cañar: Río Chauchas, 3 km N Zhud , 2910 m, 17.ix.1990, OS Flint, Jr– 1 male (pinned) ( NMNH) ; Pichincha: 7 km E Pifo , 2950 m, 26-28.ix.1990, OS Flint, Jr– 1 male (pinned) ( NMNH) .

Distribution — Ecuador.

— bilineata subgroup

Included species: Mortoniella bilineata Ulmer ; M. bulbosa , n. sp.; M. chicana Sykora ; M. hamata , n. sp.; M. monopodis , n. sp.; M. paralineata Sykora ; and M. roldani Flint.

The species in this subgroup are characterized by having 2 white forewing bands, 1 at the anastamosis, as found in many species of Mortoniella , and 1 on the proximal part of the wing. Outside the bilineata subgroup, this character is found only in two species of the flinti subgroup, which are otherwise very different in morphology. Mortoniella iridescens Flint , which is here placed in its own species group, also has two wing bands, but these are an iridescent turquoise, rather than white, and other characters do not indicate an obvious close relationship to the taxa included in this subgroup (although it may belong here). The general coloration of species in the bilineata subgroup ranges from a golden brown to brownish-black, but generally not as dark in color as species in the flinti or foersteri subgroups. The species are also characterized by the structure of tergum X, which has the ventrolateral margins curled inward in its apical part, converging on the median plane to form a “linear seam.” The resulting apex of the tergum is more or less truncate, without a pronounced apicomesal notch. Species in the apiculata subgroup are similarly developed, but differ from species of the bilineata subgroup in lacking an angulate ventral projection on the dorsal phallic spine, as well as in lacking wing bands. Species in the enchrysa, foersteri, and wygodzinskii subgroups have tergum X with the lateral margins curled inward, as in species in the bilineata subgroup, but the ventral margins of the tergum do not completely converge on the median line, leaving the apex with a distinct apicomesal notch. The loss of this notch in the bilineata and apiculata subgroups, accompanied by the distinct ventromesal seam, is considered a derived apomorphic character, and a probable indication of their close relationship.

Figures

Figure 2. Mortoniella (Mortoniella) apiculata Flint, 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.