Xiphocentron (Sphagocentron) tuxtla, Vilarino & Calor, 2024

Vilarino, Albane & Calor, Adolfo R., 2024, Comparative geometric morphometrics of male genitalia in Xiphocentron subgenera (Trichoptera: Xiphocentronidae): new species, revision and phylogenetic systematics of the subgenus Sphagocentron, Arthropod Systematics & amp; Phylogeny 82, pp. 407-431 : 407-431

Xiphocentron (Sphagocentron) tuxtla sp. nov.

Figures 12 A – D

Type material.

Holotype MEXICO • ♂; Veracruz; Los Tuxtlas area, Maquinas river 4–14. v. 1981, C. M. and O. S. Flint Jr leg., USNMENT 01518157 .

Diagnosis.

The new species is most similar to Xiphocentron guanacaste sp. nov. by having the sternum IX posterior margin with a deep mesal incision forming two prominent lobes and is similar to X. julus and X. evandrus by the paraproct shape without the round apicodorsal margin. The species can be diagnosed from this and other congeners mainly by: (1) the shape of tergum IX with the posterior margin with wide subtruncate lobes slightly divergent, (2) the inferior appendage with sparser spine-like setae at the proximal region, and the combination of (3) the sternum IX posterior margin forming prominent mesal projections divided by a narrow incision, (4) the paraproct in lateral view truncate without round apicodorsal lobe and (5) the preanal appendage subapically wide.

Description.

Male: Forewing length 4.0 mm (n = 1). Color overall pale brown, forewing overall dark brown (in alcohol). Maxillary palp segment length formula (I = II = III) <IV <V. Tibial spur formula 2: 4: 3; spurs unmodified. Forewing forks II and IV present, fork II sessile at discoidal cell; discoidal half as long as thyridial cell. Hind wing forks II and V present. Sternum V with anterolateral reticulated region.

Genitalia (Fig. 12 A – D ). Tergum IX, in lateral view, wide basally, narrowing apically (Fig. 12 A ); in dorsal view, anterior margin straight with mesal concave line; posterior margin with wide subtruncate lobes and narrow deep mesal incision (Fig. 12 B ). Sternum IX, in lateral view, about 3 × as long as high, apex truncate; anterior apodeme narrow, straight, tapering to narrow flange (Fig. 12 A ); in ventral view, about 1.5 × as long as wide, posterior margin with prominent, acute, mesal lobes devided by narrow incision (Fig. 12 C ). Tergum X membranous fused basodorsally to each paraproct. Paraproct, in lateral view, oblong, dorsoapically truncate, without round lobe, with narrow, ventral lobe (Fig. 12 A ); in dorsal view, wide basally, divided apicomesally, each side partially fused at midlenght, without clear sclerotized mesal band, apex with several sensillae (Fig. 12 B ). Preanal appendage setose, in lateral view about 2 × as long as tergum IX, straight to slightly sigmoid, distal half wide, tapering to acute apex (Fig. 12 A ); in dorsal view, substraight, tapering apically (Fig. 12 B ). Inferior appendage, in lateral view, about 2.5 × as long as tergum IX; coxopodite and harpago fused, with dorsal suture line between each article, inner face with longitudinal line of setae, area of dense, long spine-like setae, and row of regular setae from midlenght to apex (Fig. 12 A ); basal region (coxopodite) wide, without basomesal spine-like setae, mesal sclerite region with dense, longer spine-like setae (Fig. 12 A ); apical region (harpago) in lateral view narrow, digitate, 1.5 × as long as basal region, inner face with longitudinal line of setae (Fig. 12 A ); basal plate in lateral view wide, anteriorly with narrow flange (Fig. 12 A ). Phallus tubular, very long and narrow, reaching segment V; basally conical, subapically annulate, weakly sclerotized; apex slightly enlarged (Fig. 12 D ).

Etymology.

Name in apposition; named after the type locality, tuxtla comes from the nahuatl language: ‘ tochtlán’, meaning place of rabbits.

Distribution.

Mexico.

Figures

Figure 12. Xiphocentron (Sphagocentron) tuxtla sp. nov. Holotype (USNM), male. Genitalia: A left lateral, B dorsal, C ventral. Scale bar 0.1 mm.