Tytthus mexicanus Henry

Henry, Thomas J., 2012, Revision of the Plant Bug Genus Tytthus (Hemiptera, Heteroptera, Miridae, Phylinae), ZooKeys 220, pp. 1-114 : 33-36

Tytthus mexicanus Henry sp. n. Figs 19, 20144-147

Diagnosis.

This species is distinguished by the black antennae, except for the pale apex of segment I; the black pronotum; the brown mesoscutum and scutellum; the smoky brown to dirty white hemelytra; and the pale yellowish legs, with distinct black spines and knee spots at the bases of the tibiae.

Tytthus mexicanus is most similar to Tytthus femoralis and Tytthus entrerianus based on the pale tibiae with knee spots and antennal segment II lacking erect, bristlelike setae. It can be distinguished from both species by the uniformly pale hind femora and dark brown to fuscous antennal segment II.

Description.

Male (n = 4; plus holotype in parentheses) (Fig. 19): Length to apex of hemelytron 2.75-2.58 mm (2.55 mm), length to base of cuneus 2.90-2.05 mm, width across hemelytra 0.88-0.93 mm (0.86 mm). Head: Length 0.32-0.34 mm (0.30 mm), width across eyes 0.59-0.61 mm (0.59 mm), interocular width 00.27-0.29 mm (0.27 mm). Labium: Length 1.12-1.14 mm (1.12 mm). Antenna: Segment I length 0.30 -0.34 mm (0.32 mm), II 0.91-1.07 (1.02 mm), III 0.54-0.64 mm (0.58 mm), IV 0.51-0.64 mm (missing). Pronotum: Length 0.34-0.35 mm (0.32 mm), basal width 0.78-0.82 mm (0.77 mm).

Coloration: Head: Uniformly fuscous to black, with a large, distinct, pale yellow, interocular spot near inner margin of each eye, spots nearly contiguous in some specimens; eyes reddish brown, often fading to silver with a reddish tinge. Labium: Uniformly pale yellow; apex of segment IV dark brown to fuscous. Antenna: Segment I fuscous to black, with apical one fourth yellow (length of yellow area equal to diameter of segment) and narrowed basal one fourth shiny; segment II dark brown to black (basal area darker on “paler” dark brown segments); segments III and IV dark brown to fuscous. Pronotum: Uniformly shiny fuscous, weakly swollen calli sometimes very slightly paler brown. Mesoscutum: Dark brown to fuscous, lateral angles pale yellow on some specimens. Scutellum: Dark brown to fuscous, slightly paler apically. Hemelytron: Pale translucent smoky brown to dirty white; veins brown and often narrow inner margin of clavus brown. Ostiolar evaporative area: Dark brown to fuscous, often invaded with pale areas posteriorly. Ventral surface: Thorax uniformly dark brown to fuscous; abdomen dark brown to fuscous laterally, pale ventrally, genital capsule black. Legs: Coxae pale brownish yellow, with bases brown; femora uniformly pale yellow to whitish; tibia pale yellow to whitish with spines and bases, or knees, dark brown to fuscous; tarsi and claws pale yellow.

Structure, texture, and vestiture: Head: Shiny, impunctate, wider than long; buccula relatively narrow, ending posteriorly near level with middle of eye; sparsely set with long, erect and suberect, pale brown to brown setae. Labium: Extending to bases of hind coxae or just onto abdominal segment II; segment I extending to bases of fore coxae. Antenna: Segment I with short, recument setae and two long, black, bristlelike setae near apex before pale area; segment II thickly set with short, recumbent pale brown setae much shorter than diameter of segment. Pronotum: Shiny, impunctate; calli weakly swollen but distinct; anterior rounded; lateral margins concave, strongly flaring at posterior angles; posterior margin weakly sinuate; set with short, erect to semierect setae. Mesoscutum: Shiny, impunctate, broadly exposed; with numerous semierect and recumbent, pale brown setae. Scutellum: Shiny, impunctate; thickly set with semierect and recumbent pale brown setae. Hemelytron: Macropterous, subparallel when paired, with fully developed cuneus and membrane, extending well beyond apex of abdomen; evenly scattered with short, recumbent, pale brown setae.

Male genitalia: (Fig. 144): Mitt-shaped; right arm longest, stout, slightly constricted basally, weakly pointed apically; left arm short, apically acute. Right paramere (Fig. 145): Elongate oval, strongly rounded apically. Endosoma (Fig. 146): C-shaped, nearly S-shaped with apical quarter curving slightly upward. Phallotheca (Fig. 147): moderately stout, apically acute.

Female:(n = 2) (Fig. 20): Length to apex of hemelytron 2.88-2.93 mm, length to base of cuneus 2.10-2.23 mm, width across hemelytra 0.99-1.04 mm. Head: Length 0.32-0.37 mm, width across eyes 0.61-0.62 mm, interocular width 0.29-0.30 mm. Labium: Length 1.20-1.22 mm. Antenna: Segment I length 0.29-0.30 mm, II 0.88- 0.91 mm, III 0.61-0.64 mm, IV 0.61-0.62 mm. Pronotum: Length 0.35-0.37 mm, basal width 0.86-0.88 mm.

Similar to male in general color and pubescence, differing primarily in the slightly broader form.

Etymology.

Named for the country in which it was collected, Mexico.

Host.

Unknown.

Distributon.

Known only from Baja California Sur, Nayarit, and Sinaloa, Mexico.

Type material.

Holotype ♂ (00166142) (USNM): MEXICO:Sinaloa:Culiacan Co.: Camino Real Tres Rios, 3 km N Mex. 15 at toll bridge gate, 08 Aug 1981, S. Nichols. Paratypes: MEXICO:Nayarit: San Blas, 16 Oct 1973, S.C. Williams, K.B. Blair, & C.L. Mullinex, 1 ♂ (00409874), 1♀ (00409875) (CAS). Sinaloa:Culiacan Co.: Camino Real Tres Rios, 3 km N Mex. 15 at toll bridge gate, 08 Aug 1981, S. Nichols, 2 ♂ (00163423, 00166141) (USNM). Other Paratypes: MEXICO:Baja Calif. Sur: San Javier 11 Oct 1981, D. Faulkner & F. Andrews, at blacklight, 1 ♂ (CDFA). 112.2 mi SE San Perdito near Rancho Saucito, 8 Oct 1981, F. Andrews & D. Faulkner, 1 ♀ (SDNH). Nayarit: Choix, 5 Aug 1968, A. Sears, R. C. Gardner, & C. S. Glaser, 1 ♂ (UCD). 5.5 mi NW Choix, 14 Jul 1968, A. Sears, R. C. Gardner, & C. S. Glaser, 1 ♀ (UCD). Mazatlan, 27 Mar 1979, L. D. French, 1 ♂ (UCD).