Mortoniella (Mortoniella) squamata Sykora, 1999

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 : 32-33

Mortoniella (Mortoniella) squamata Sykora, 1999

Fig. 17

Mortoniella squamata Sykora 1999: 379 [member of bilineata subgroup]; Blahnik and Holzenthal 2008: 70 [member of bilineata group].

This species was considered a member of the bilineata subgroup by Sykora 1999, who commented on its color as golden beige. The color is actually very similar to other species in the enchrysa subgroup, though perhaps not quite as brilliantly colored. Other characters also indicate that this is where it should be placed. It is smaller than most of the species in the group. The species is probably most closely related to M. adamsae , n. sp. Both species have 2 pairs of paramere appendages. Those of M. squamata are both armed with small accessory spines, whereas only the longer pair in M. adamsae is spined. The general form of tergum X is also similar, with a relatively shallow apical notch. The two species are easily distinguished by the overall shape of the inferior appendages, in addition to the difference in the paramere appendages.

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. Dorsal side of forewings, head, basal segments of antennae, and legs, except distal parts of tibiae and tarsi, golden (ochraceous); ventral side of forewings (and apicomarginal setae), hind wings, apices of antennae, and palps, dark brownish-black; legs with scattered dark setae, especially at apices of tibiae and tarsal segments. Forewings (apparently) somewhat infuscated. Tibial spurs brownish-black, contrasting with legs. Wing bars absent

Male genitalia —Ventral process of segment VI posteriorly projecting, short, narrow basally, length about 2 times width at base. Tergum VIII relatively narrow, subtending ventral margin of segment IX, membranous connection to tergum IX elongate. Segment IX with anterolateral margin rounded and produced in ventral half, posterolateral margin with distinctly angular 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 with basal part inflated and distinctly set off from apical part, tergum moderately elongate, lateral margins weakly rounded, ventrolaterally with short acute lateral lobes, each with prominent apical seta; apex of tergum distinctly sclerotized and emarginated mesally, lateral lobes truncate, with ventrolateral margins incurved and approaching each other mesally, but separated by distinct gap, apicodorsally with short U-shaped connection near apex (mesal notch distinct); tergum ventromesally with paired, rounded and sclerotized, ventromesal lobes in basal half, each with short setae. Inferior appendages with short setose dorsolateral lobes and single short ventromesal lobe, as viewed ventrally. Mesal pockets of inferior appendage with only moderately elongate, posteriorly-directed, spine-like, apicoventral projections, projections apparently fused to ventral margin of phallicata. Parameres with paired appendages on either side, both relatively elongate, narrow, with numerous small adpressed, spine-like projections, dorsal pair relatively straight, ventral pair strongly bowed or curved in apical ½; fused basal segments of parameres articulating near base of dorsal phallic spine, ventral margins with numerous microsetae and (apparently) sclerously fused to and more or less continuous with base of phallicata. Phallobase with relatively small rounded, laterally compressed, dorsomesal apodeme. Dorsal phallic spine, as viewed laterally, with dorsal margin curved basally, nearly straight in middle part and strongly, nearly rectilinearly, upturned in apical ¼, apex of spine rounded; base of spine narrow, undulately curved and stalk-like, widened on ventral margin in basal ½, forming rounded, non-angular, ventral projection, narrowing apically from projection; spine, as viewed dorsally, somewhat widened at ventral enlargement, basal and apical parts narrow, apex rounded. Phallicata with sclerotized basodorsal projection, articulating with rounded ventral projection of dorsal phallic spine; phallicata ventrally with 2 pairs of diverging sclerotized lobes (butterfly-like), basal ones retrorsely oriented, rounded laterally, posterior pair diverging from posterior margin of basal lobes, apices bluntly rounded, posteriorly projecting; ventromesal margin of phallicata extending somewhat beyond paired lobes, very lightly sclerotized, extending about same length as paramere appendages. Endophallic membrane simple in structure, without apparent membranous lateral lobes; phallotremal spines absent.

Material examined — ECUADOR: Napo: 5 km S Baeza, 1900 m, 10.ix.1990, OS Flint, Jr– 1 male Paratype (pinned) (NMNH).

Distribution — Ecuador.

— flinti subgroup

Included species: Mortoniella bifurcata Sykora ; M. flinti Sykora ; M. tanyrhabdos , n. sp.; and M. tusci , n. sp.

This subgroup of the bilineata group was originally proposed by Sykora (1999), but included what is probably a heterogeneous assemblage of species. We are restricting the definition of the group to include two species listed by Sykora, M. flinti and M. bifurcata , and two new species. A distinct, but unassociated, female specimen reveals that at least 1 additional species belongs to the group. As redefined, the group is very homogeneous and all of the species are obviously closely related. Known species in the group are restricted to Venezuela. All of the species are relatively small for species in the bilineata group and very dark in color, with the mesotarsi white or whitish, except at the very apex. A white or whitish band is also evident in the basal part of the antennae in most specimens; the band occurs in the apical part of the antennae in the undescribed female specimen. Similar white markings are found on the legs and antennae of at least some species of the bilineata subgroup, but this is probably a homoplasious similarity, since the overall differences between the two subgroups are considerable. The flinti subgroup shares basic features that characterize the bilineata group as a whole, including an anteroventrally produced segment IX, elongate narrow ventral process on segment VI, and females with a strongly invaginated tergum VIII. However, unlike most other species in the bilineata group, the posterior margin of segment IX of males in the flinti subgroup is not angular and only slightly produced, the ventral margin of the of the dorsal phallic spine is not angularly articulated with the phallicata, and the apex of the dorsal phallic spine is neither abruptly upturned nor rounded apically in lateral view. In all of the species of this group the inferior appendages have very fine, elongate setae on the dorsal margin of the dorsal lobe, and the assemblage of the inferior appendages with the phallicata seems to be more or less fused, so that the elongate spines from the mesal pockets of the inferior appendages are separated from and project below the ventral margin of the phallicata, which is characteristically arched. Tergum X is elongate and more or less entire (notched apically in M. flinti ), without the paired sclerotized apicolateral lobes that characterize species in the M bilineata , apiculata, and enchrysa subgroups. The species in this subgroup also lack the projecting ventromesal lobes on tergum X that characterize the species of the bilineata, apiculata, enchrysa, foersteri, iridescens, and wygodzinskii subgroups. The flinti subgroup species are unusual for species of the bilineata group in having only 3 tibial spurs on the mesotibiae and in lacking fork III in the hind wing (only forks II and V present). The latter venational combination is unique with the genus Mortoniella .

Figures

Figure 17. Mortoniella (Mortoniella) squamata Sykora, 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.