Tytthus pubescens (Knight)

Henry, Thomas J., 2012, Revision of the Plant Bug Genus Tytthus (Hemiptera, Heteroptera, Miridae, Phylinae), ZooKeys 220, pp. 1-114 : 61-64

Tytthus pubescens (Knight) Figs 38 –4079–86171– 174

Capsus geminus Flor 1860: 464 (orig. descrip.). Preoccupied by Capsus geminus Say, 1832 as noted by Henry and Wheeler 1988: 457.

Cyrtorhinus geminus : Reuter 1883: 382 (descrip.); Butler 1923: 480 (biol.); Wagner 1952: 129 (descrip., key).

Chlamydatus (Cyrtorhinus) geminus : Reuter 1875b: 126 (descrip.).

Cyrtorhinus pubescens Knight 1931: 172 (orig. descrip.). Synonymized by Carvalho and Southwood 1955: 28; resurrected by Henry and Wheeler 1988: 457.

Tytthus geminus : Fieber 1864: 83 (comb.); Carvalho and Southwood 1955: 28 (comb., descrip., distr., key); Kiritshenko 1951: 175 (key); Carvalho 1952: 81 (list); Carvalho 1958: 157 (cat.); Kerzhner 1964: 754 (key); Kelton 1980: 303 (descrip.host, distr.).

Tytthus geminus form flori Stichel 1956: 271 (orig. descrip.).

Tytthus geminus form pallidior Stichel 1956: 271 (orig. descrip.).

Tytthus pubescens : Henry and Wheeler 1988: 457 (cat., revised status); Wheeler and Henry 1992: 140 (distr., host); Polhemus 1994: 133 (list); Schuh 1995: 249 (cat.); Scudder 1997: 270 (distr., hosts); Kerzhner and Jovifov 1999: 442 (cat.); Maw et al. 2000: 121 (list); Wachman et al. 2004 (note, biol.); Wheeler 2011: 209 (distr., hosts).

Diagnosis.

This species is distinguished by the fuscous to black head; brown to black pronotum, often entirely or with only the posterior angles or posterior half whitish to pale brown; the pale yellow to yellowish brown antennal segment I and black segments II -IV; the long, erect setae in both sexes on antennal segment II as long or longer than the diameter of the segment; the uniformly pale, translucent hemelytra; and pale brownish yellow legs. Males of this species are always macropterous (Fig. 38); both macropters (Fig. 39) and brachypters (Fig. 40) are known for females, but brachypters are most common.

This Holoarctic species is superficially similar to another Holarctic species, Tytthus pygmaeus, in general color and size. Tytthus pubescens is readily distinguished by the pale antennal segment I, the long erect and semierect setae on antennal segments I and II, and the often pale humeral pronotal angles.

Description.

Macropterous male (n = 10) (Figs 38, 79, 80): Length to apex of hemelytron 2.59-3.01 mm, length to base of cuneus 1.98-2.37 mm, width across hemelytra 0.93-0.96 mm. Head: Length 0.30-0.32 mm, width across eyes 0.64-0.66 mm, interocular width 0.30-0.32 mm. Labium: Length 1.01-1.07 mm. Antenna: Se gment I length 0.35-0.38 mm, II 0.88-0.94 mm, III 0.62-0.66 mm, IV 0.56-0.58 mm. Pronotum: Length 0.35-0.40 mm, basal width 0.74-0.78 mm.

Coloration: Head (Figs 81-83): Fuscous to black, with a small, yellow, interocular spot near inner margin of each eye; eyes reddish brown. Labium: Segments I–III pale yellow; segment IV brown. Antenna: Segment I pale yellow; segment II–IV fuscous to black. Pronotum: Uniformly fuscous to black, some specimens brown at posterior angles, others pale brown on posterior half, sometimes with dark brown invading darker anterior half. Mesoscutum and Scutellum: Fuscous to black. Hemelytra: Pale translucent yellow to whitish. Ostiolar evaporative area (Fig. 84): Fuscous to black. Ventral surface: Thorax and abdomen uniformly fuscous to black. Legs: Coxae pale yellow, the bases brown; femora, tibiae, tarsi, and claws (Fig. 86) uniformly pale yellow.

Structure, texture, and vestiture: Head: Weakly shiny, impunctate; set with relatively long, erect and semierect setae on vertex and frons. Labium: Extending to apices of meso- or bases of metacoxae; segment I extending just past base of head to anterior margin of xyphyus before procoxae. Antenna: Segment I set with rather short, sparse, recumbent setae and two to four or more long, erect, subapical, bristlelike setae; segment II densely set with short, recumbent setae, intermixed with erect and semierect setae mostly subequal in length to diameter of segment. Pronotum: Nearly rectangular; anterior angles rounded; lateral margins straight, only slightly widening to posterior angles; posterior margin straight or only very slightly sinuate; set with relatively long, recumbent and semierect setae. Mesoscutum: Broadly exposed, even in brachypters; with a few scattered, semierect setae. Scutellum: weakly shiny, equilateral; set with relatively long, semierect setae. Hemelytron: Macropterous, subparallel; cuneus and membrane fully developed, extending beyond apex of abdomen; evenly set with recumbent setae.

Male genitalia (Fig. 85): Left paramere (Fig. 171): Right arm broad, widened through middle, tapering to a fine point apically; left arm short, apically pointed. Right paramere (Fig. 172): Elongate oval. Endosoma (Fig. 173): Strongly C-shaped, apically blunt. Phallotheca (Fig. 174): Broad, apically acute.

Macropterous female (n = 10) (Fig. 39): Length to apex of hemelytron 2.66-3.10 mm, length to base of cuneus 1.98-2.24 mm, width across hemelytra 1.06-1.15 mm. Head: Length 0.30-0.32 mm, width across eyes 0.64-0.67 mm, interocular width 0.32-0.34 mm. Labium: Length 1.12-1.15 mm. Antenna: Segment I length 0.29-0.30 mm, II 0.69-0.72 mm, III 0.51-0.54 mm, IV 0.48-0.51 mm. Pronotum: Length 0.35-0.38 mm, basal width 0.82-0.93 mm.

Macropters have normally developed hemelytra that extend well beyond the apex of the abdomen as in males. Out of 63 females examined, only 10 are macropterous.

Brachypterous female (n = 10) (Fig. 40): Length to apex of abdomen 2.34-2.66 mm, length to base of cuneus 2.05-2.11 mm, width across hemelytra 0.94-1.15 mm. Head: Length 0.32-0.34 mm, width 0.67-0.69 mm, interocular width 0.32-0.34 mm. Labium: Length 1.10-1.17 mm. Antenna: Segment I length 0.27-0.32 mm, II 0.75-0.80 mm, III 0.50-0.54 mm, IV 0.45-0.53 mm. Pronotum: Length 0.40-0.42 mm, basal width 0.75-0.83 mm.

Brachypters are broadly rounded, with the cuneus sometimes slightly shortened and membrane greatly reduced and not attaining the apex of the abdomen.

Host.

In North America, this species has been collected on Carex sp. ( Kelton 1980) and Carex utriculata Boott [ Cyperaceae ] (Wheeler 2011). It has been taken on rushes, sedges, and grasses in England where it is said to prey on leafhopper eggs ( Butler 1923, Southwood and Leston 1959, Rothschild 1963, Wheeler and Henry 1992). Specimens from Arizona were beaten from clumps of deer grass, Muhlenbergia rigens (Benth.) Hitchc. [ Poaceae ].

Distribution.

This Holarctic species was previously known in North America from Alaska, Alberta, British Columbia, Colorado, Newfoundland, New Mexico, Quebec, Saskatchewan, and Yukon Territory (Henry and Wheeler 1988, Wheeler and Henry 1992, Polhemus 1994, Maw et al. 2000, Wheeler 2011). Arizona is a new state record.

In the Old World, it is known in Asia from Russia (East Siberia, Far East, and West Siberia) and in northern Europe from Austria, Byelorussia, Czech Republic, Denmark, Estonia, Finland, France, Great Britain, Germany, Hungary, Ireland, Latvia, Luxembourg, Moldavia, The Netherlands, Norway, Poland, Russia (Central European and Northern European territories), Slovakia, Sweden (Wheeler and Henry 1992, Kerzhner and Josifov 1999).

Type material examined.

Holotype ♀ (brachypterous) of Tytthus pubescens (USNM) UNITED STATES: Colorado : Wray, 4 Aug 1925, H. H. Knight (USNM).

Other specimens examined.

CANADA:Alberta: Jasper National Park, Banff-Jasper Highway, 26 Aug 1970 - 28 Aug 1970, L. A. Kelton, Carex sp. ( Cyperaceae ), 24 ♀♀ (00167011 - 00167034) (CNC). McMurray, 56.73333°N, 111.38333°W, 11 Jul 1953, W. J. Brown, 1 ♀ (00167052) (CNC). British Columbia: Atlin, 59.58333°N, 133.71666°W, 2199 m, 21 Jul 1955, B. A. Gibbard, 1 ♀ (00167051) (CNC); 14 Aug 1955, H. J. Huckel, 2 ♀♀ (00167037, 00167050) (CNC). Pink Mountain, 57.05°N, 122.86666°W, 17 Aug 1982, L. A. Kelton, 1 ♀ (00167141) (AMNH). Pouce Coupe, 55.7167°N, 120.1333°W, 18 Aug 1982, L. A. Kelton, Beckmannia syzigachne ( Poaceae ), 1 ♂ (00167036) (CNC). Terrace, 54.51241°N, 128.59637°W, 67 m, 27 Jul 1960, collector unknown, 1 ♀ (00166931) (CNC). Ontario: Fergus, 43.7°N, 80.36666°W, 24 Jul 1962, Kelton and Thorpe, 1 ♂ (00167055) (CNC). Quebec: Bonaventure Co., Escuminac, 48.11667°N, 66.48333°W, 2 m, 22 Aug 1983, Larochelle and Lariviere, 2 ♀♀ (00167046, 00167047) (CNC). Lac Mondor, Ste. Flore, 46.61666°N, 72.76666°W, 06 Jul 1951, E. G. Munroe, 1 ♂ (00167010) (CNC). Saskatchewan: Candle Lake, 53.74996°N, 105.25°W, 499 m, 19 Aug 1959, A. and J. Brooks, 1 ♂ (00167008) (CNC). Elbow, 51.11666°N, 106.6°W, 14 Jul 1960, A. R. Brooks, 1 ♂ (00167006) (CNC). Yukon Territory: 58 mi E of Dawson, Gravel Lake, 64.06666°N, 137.49935°W, 625 m, 12 Aug 1962, R. E. Leech, 1 ♀ (00167035) (CNC). Haines Junction, 60.75°N, 137.5°W, 28 Jul 1982, L. A. Kelton, 1 ♂ (00167005), 1 ♀ (00167004) (CNC). Koidern, 61.98333°N, 140.5°W, 24 Jul 1982, L. A. Kelton, 2 ♀♀ (00167038, 00167039) (CNC). Moose Creek, 18 Jul 1982, L. A. Kelton, 1 ♂ (00167009) (CNC). Rancheria, 60.08333°N, 130.6°W, 28 Jul 1982, L. A. Kelton, 1 ♂ (00167007) (CNC). Tagish, 60.3°N, 134.26666°W, 11 Aug 1983, L. A. Kelton, 6 ♀♀ (00167041 - 00167045, 00167053) (CNC). Takhini Hot Springs, 60.85°N, 135.51666°W, 732 m, 19 Aug 1962, R. E. Leech, Betula sp. ( Betulaceae ), 2 ♂♂ (00167000, 00167001), 2 ♀♀ (00167002, 00167003) (CNC). FINLAND:Lansi-Suomen: Pargas (Parainen), 60.3°N, 22.3°E, V. Jakovlev coll., 1 ♀ (00235128) (ZISP). Raisio, 60.4833°N, 22.1833°E, 28 m, R. Linnavuori, 1 ♀ (00161842) (USNM); Suomi V Raisio, 16 Sep 1947, R. Linnavuori, 2 ♀♀ (BMNH). Lapland: Pisavaara Nature Reserve, 03 Jul 1950, Hakan Lindberg, 1 ♂ (00161847) (USNM); 14 Jul 1950, Hakan Lindberg, 1 ♀ (00167054) (CNC). Southern Finland:Uusimaa Co.: Ekenas, 24 Jul 1936, Hakan Lindberg, 1 ♀ (00161843) (USNM). Helsinki, 19 Aug 1946, Hakan Lindberg, 2 ♀♀ (00167048, 00167049) (CNC). Western Finland: Pargas, 1900, Reuter, 2 ♂♂ (00161845, 00161846), 1 nymph (00161844) (USNM); Pargus J. Sahlberg, Saunders coll., Brit. Mus. 1910-357, 1 ♀ (BMNH). Kiumvesi, 4 Aug. 1951, R. Linnavuori, 1 ♂, 1 ♀ (NMW). RUSSIAN FEDERATION:Kostroma Prov.: Ugory, Manturovskiy Dist., 58.13333°N, 44.35°E, 09 Sep 1983, Veselova, Carex gracilis ( Cyperaceae ), 3 ♀♀ (00235130) (ZISP). Leningrad Prov.: St.-Petersburg [Petrograd], Novaya Derevnya, 59.98333°N, 30.26666°E, 15 Aug 1924, A. N. Kiritshenko, 2 ♂♂ (00235136), 3 ♀♀ (00235133 - 00235134, 00235136) (ZISP). UNITED KINGDOM:England:Locality unknown Co.: 1800, C. F. Baker, 1 ♂ (00161837) (USNM). UNITED STATES:Alaska:Anchorage Co.: 30 mi NE of Anchorage, 04 Aug 1948, R. I. Sailer, 1 ♂ (00161832), 2 ♀♀ (00161830, 00161831) (USNM). Arizona:Santa Cruz Co.: Audubon Research Ranch, Elgin, Finley Tank, 14 May 2004, A. G. Wheeler, Jr., Muhlenbergia rigens ( Poaceae ), 1 ♂ (00161835), 1 ♀ (00161833), 1 nymph (00161834) (USNM). Colorado:Garfield Co.: Grizzly Creek, 1896, C. F. Baker, 1 ♂ (00161838) (USNM). Larimer Co.: Chambers Lake, 01 Aug 1896, C. F. Baker, 1 ♀ (00161839) (USNM). Mountain Park Campground, Roosevelt National Forest, 40.6825°N, 105.4675°W, 2012 m, 06 Aug 1968, L. A. Kelton, 1 ♀ (00167040) (CNC). Yuma Co.: Wray, 40.07583°N, 102.22278°W, 1128 m, 04 Aug 1925, H. H. Knight, 1 ♂ (00162204) (USNM). ‘Colo’ 2074, 1900, P.R. Uhler Collection, 1 ♀ (00161840) (USNM). Idaho:Idaho Co.: 10.2 mi WSW of Lolo Pass, Powell Pasture, 46.46274°N, 114.89083°W, 1097 m, 22 Jul 1978, N. L. Herman, 1 ♂ (00166051) (AMNH). New Mexico:Sandoval Co.: Valles Caldera National Preserve, East Fork Jemez River, 35.8483°N, 106.49048°W, 20 Aug 2007, A. G. Wheeler, Jr., 1 ♀ (00161836) (USNM); 01 Aug 2008, A. G. Wheeler, Jr., Carex utriculata ( Cyperaceae ), 4 ♂♂ (00162194 - 00162197), 6 ♀♀ (00162188 - 00162193) (USNM). Valles Caldera National Preserve, Main Road at East Jemez River, 35.84826°N, 106.49051°W, 17 Aug 2009 - 18 Aug 2009, A. G. Wheeler, Jr., Carex utriculata ( Cyperaceae ), 4 ♂♂ (00162184 - 00162187) (USNM). Valles Caldera National Preserve, below historic ranch headquarters, 35.86363°N, 106.51681°W, 17 Aug 2009 - 18 Aug 2009, A. G. Wheeler, Jr., Carex utriculata ( Cyperaceae ), 7 ♂♂ (00162177 - 00162183), 13 ♀♀ (00162164 - 00162176) (USNM).