Tytthus fuscicornis Henry

Henry, Thomas J., 2012, Revision of the Plant Bug Genus Tytthus (Hemiptera, Heteroptera, Miridae, Phylinae), ZooKeys 220, pp. 1-114 : 28-30

Tytthus fuscicornis Henry sp. n. Figs 15, 16132-135

Diagnosis.

This new species is distinguished by the small size, the uniformly dark brown head and pronotum, fuscous to black antennae with segment II thickened and subequal to apical diameter of segment I, the pale or whitish hemelytra, and the brownish-yellow legs. The only known male (holotype) of this species is macropterous and the only known female is brachypterous with an abbreviated membrane.

It is superficically similar to several species, such as Tytthus mexicanus and Tytthus panamensis , based on the dark head, pronotum and scutellum and pale hemelytra. It is distinguished from these and all other species by the pale tibiae lacking knee spots, uniformly fuscous antennae, the thickened antennal segment II, pale femora, and relatively small size.

Description.

Holotype male (Fig. 15): Length to apex of hemelytron 2.14 mm, length to base of cuneus 1.54 mm, width across hemelytra 0.69 mm. Head: Length 0.29 mm, width across eyes 0.51 mm, interocular width 0.29 mm. Labium: Length 0.69 mm. Antenna: Segment I length 0.22 mm, II 0.75 mm, III 0.43 mm, IV 0.29 mm. Pronotum: Length 0.27 mm, basal width 0.67 mm.

Coloration: Head: Uniformly dark brown, with a somewhat indistinct, small, yellow interocular spot near inner margin of eye; eyes dark brown to reddish brown, especially around margins. Labium: Uniformly brownish yellow, with only apex of segment IV dark brown or fuscous. Antenna: Uniformly fuscous to black. Pronotum: Uniformly dark brown. Mesoscutum: Dark brown. Scutellum: Dark brown. Hemelytron: Pale or whitish, evenly tinged with pale brown; membrane pale translucent brown. Ostiolar evaporative area: Pale brownish yellow. Ventral surface: Propleura dark brown; ventral areas of thorax and abdomen reddish brown, genital capsule darker brown to nearly black. Legs: Coxae pale to pale brownish yellow, with bases reddish brown; femora brownish yellow, tinged with orange or brownish orange; tibiae, tarsi, and claws pale browish yellow.

Structure, texture, and vestiture: Head: Shiny, impunctate; buccula slender, ending posteriorly about level with middle of eye; sparsely set with very short, recumbent and semierect, setae. Labium: Extending to apices of meso- or bases of metacoxae; segment I short, extending only slightly beyond base of head. Antenna: Segment I with only a few short, recumbent setae and two erect, subapical, bristlelike setae; segment I densely set with short, recumbent setae; segment II gradually thickened to apex, apical width equal to or greater than diameter of segment I. Pronotum: Shiny, impunctate; calli weakly swollen; anterior angles rounded; lateral margins nearly straight, gradually widening to posterior angles; basal margin weakly concave; sparsely set with only short, recumbent setae. Mesoscutum: Narrowly exposed; sparsely set with short, recumbent setae. Scutellum: Impunctate, weakly shiny; sparsely set with short, recumbent setae. Hemelytron: Entire, suparallel; length of cuneus about two times basal width; membrane with two areoles, extending well beyond apex of abdomen.

Male genitalia: Left paramere (Fig. 132): Mitt-shaped; right arm long, evenly slender, and rounded apically; left arm short, apically acute. Right paramere (Fig. 133): elongate oval. Endosoma (Fig. 134): C-shaped or weakly S-shaped. Phallotheca (Fig. 135): Relatively slender, apically acute.

Brachypterous female (n = 1; somewhat teneral) (Fig. 16): Length to apex of hemelytron 1.57 mm, length to base of cuneus 1.36 mm, width across hemelytra 0.70 mm. Head: Length 0.27 mm, width across eyes 0.53 mm, interocular width 0.32 mm. Labium: Length 0.64 mm. Antenna: Segment I length 0.19 mm, II 0.61 mm, III 0.40 mm, IV 0.27 mm. Pronotum: Length 0.27 mm, basal width 0.67 mm.

Similar to male in general coloration, but differing in the broader, more oval form, the slightly more slender antennal segment II (but with apex still nearly equal to apical diameter of segment I), and abbreviated hemelytron, with the length of the cuneus subequal to the basal width and the membrane shortened and extending only to the apex of the abdomen.

Host. Beaten by A. G. Wheeler from crowns of Muhlenbergia rigens (Benth) Hitchc. [ Poaceae ].

Distribution.

Known only from New Mexico, USA.

Type material.

Holotype ♂ (00161896) (USNM): UNITED STATES:New Mexico:Grant Co.: Little Walnut Road, Gila National Forest, North of Silver City, 12 May 2008, A. G. Wheeler, Jr. Paratype: Same data as for holotype, 1 ♀ (00161895) (USNM).