Tytthus mundulus (Breddin)

Henry, Thomas J., 2012, Revision of the Plant Bug Genus Tytthus (Hemiptera, Heteroptera, Miridae, Phylinae), ZooKeys 220, pp. 1-114 : 39-41

Tytthus mundulus (Breddin) Figs 24, 25152-155

Periscopus mundulus Breddin 1896: 106 (orig. descrip).

Cyrtorhinus mundulus : Reuter 1902: 178 (descrip.); Kirkaldy 1908: 378 (list); Poppius 1914: 168 (list); Muir 1920: 125 (notes); Williams 1931: 103 (notes); Swezey 1936: 79 (notes, history); Usinger 1939: 271 (key, host); Zimmerman 1948: 206 (note); Usinger 1951: 4 (descrip.).

Tytthus mundulus : Carvalho and Southwood 1955: 26 (key, descrip.); Carvalho 1958: 158 (cat.); Nguyen et al.1984: 265 (note); Henry and Wheeler 1988: 458 (cat.); Schuh 1995: 249 (cat.); Cassis and Gross 1995: 204 (cat., hosts); Kerzhner and Josifov 1999: 441 (cat.); Wheeler 2000: 665 (hosts, biol., distr.), 2001: 278 (hosts, biol., distr.); Yasunaga et al. 2001: 182 (note, photo).

Diagnosis.

Tytthus mundulus is distinguished by the fuscous to black head, pronotum, and scutellum; the translucent hemelytra with the clavus, most of the corium, and membrane tinged with brown; and the yellow legs and antennal segment I (apex sometimes narrowly infuscated), with contrasting fuscous to black antennal segments II–IV. Antennal segment II has short erect setae along the entire dorsal and ventral surface (most evident ventrally), similar to those found on in Tytthus chinensis and Tytthus parviceps ; Tytthus mundulus , however, lacks the fuscous knee spots found in these two species. All known specimens of this species are macropterous.

Description.

Male (n =5) (Fig. 24): Length to apex of hemelytron 3.07-3.26 mm, length to base of cuneus 2.21-2.30 mm, width across hemelytra 0.93-1.01 mm. Head: Length 0.34-0.35 mm, width across eyes 0.70-0.72 mm, interocular width 0.34-0.35 mm. Labium: Length 1.04-1.15 mm. Antenna: Segment I length 0.38-0.40 mm, II 1.23-1.26 mm, III 0.66-0.67 mm, IV 0.54-0.56 mm. Pronotum: Length 0.38-0.40 mm, basal width 0.83-0.86 mm.

Coloration: Head: Uniformly black, with an indistinct, pale yellow, interocular spot near inner margin of each eye; eyes dark reddish brown. Labium: Pale yellow, with only apical half of segment IV brown. Antenna: Segment I pale yellow, sometimes tinged with pale brownish orange, apex sometimes narrowly dark brown; segments II–IV dark brown to fuscous. Pronotum: Uniformly shiny, black. Mesoscutum: Shiny black. Scutellum: Shiny black. Hemelytron: Clavus, inner two thirds of corium and most of membrane tinged with brown to dark brown, leaving only outer margin of corium clear. Ostiolar evaporative area: Dark brown to fuscous. Ventral surface: Uniformly dark brown to fuscous. Legs: Coxae yellow, with bases dark brown to fuscous; femora, tibiae, tarsi, and claws uniformly yellow.

Structure, texture, and vestiture: Head: Shiny, impunctate, with a glaucous patch along inner margin of each eye; wider than long; buccula relatively broad, ending near level with posterior margin of eye; sparsely set with short, recumbent setae, more so on glaucous patches, and with a few longer, erect setae along posterior margin. Labium: Extending to bases of mesocoxae; segment I extending beyond base of head to anterior edge of prosternum. Antennae: Segment I sparsely set with short, fine, recumbent setae and two erect, subapical, bristlelike setae; segment II thickly set dorsally and ventrally with short, erect and semierect, somewhat bristlelike setae, forming a “bottlebrush” appearance (similar to Tytthus chinensis). Pronotum: Shiny, impunctate; calli weakly swollen; anterior angles rounded; lateral margins weakly concave, moderately flaring at posterior angles; posterior margin sinuate; thickly set with semierect and recumbent setae. Mesoscutum: Shiny, impunctate, broadly exposed; with semierect and recumbent setae. Scutellum: Shiny, impunctate, equilateral; thickly set with semierect and recumbent setae. Hemelytron: Macropterous, subparallel when paired, with fully developed cuneus and membrane, extending well beyond apex of abdomen.

Male genitalia: Left paramere (Fig. 152): Mitt-shaped; right arm longest, gradually tapering to a point; left arm short, apically acute. Right paramere (Fig. 153): Elongate oval. Endosoma (Fig. 154): Strongly C-shaped. Phallotheca (Fig. 155): Relatively slender, apically acute.

Female (n = 5) (Fig. 25): Length to apex of hemelytron 3.07-3.64 mm, length to base of cuneus 2.27-2.66 mm, width across hemelytra 1.04-1.22 mm. Head: Length 0.35-0.37 mm, width across eyes 0.74-0.77 mm, interocular width 0.35-0.37 mm. Labium: Length 1.06-1.22 mm. Antenna: Segment I length 0.34-0.38 mm, II 0.98 - 1.10 mm, III 0.58-0.59 mm, IV 0.50-0.58 mm. Pronotum: Length 0.40-0.43 mm, basal width 0.91-1.01 mm.

Hosts.

This species is an egg predator of the sugarcane delphacid, Perkinsiella sacharicida Kirkaldy (Zimmerman1948, Wheeler 2001). It has also been taken on corn and taro in Hawaii.

Distribution.

This Indo-Pacific species has been reported from Fiji, Hawaii, New Caledonia, Papua New Guinea, the Philippine Islands, and Queensland, Australia ( Schuh 1984). It has been successfully introduced into Hawaii to control the sugarcane delphacid ( Zimmerman 1948, Carvalho and Southwood 1955), representing one of the best examples of successful classical biological control (Wheeler 2001). It was released in Florida, according to Nguyen et al. (1984), but apparently it has not become established (Wheeler 2001). It was also introduced into South Africa to control a tropiduchid, Numicia viridis Muir, on sugarcane but without success ( Carnegie and Harris 1969). See Wheeler (2001) for additional information about this beneficial species.

Specimens examined.

AUSTRALIA:Queensland:North Queensland Co.: Halifax Apr. 1920, F. Muir, 1 ♀ (BMNH). Upper Mulgrave River, 8 miles from Goldsborough Road, 09 May 1967, D. H. Colless, 1 nymph (00161946) (USNM). FIJI: Natova, Apr. 1919, R. Veitch, 1 ♂, 5♀♀ (BMNH). MAURITIUS: Locality unknown, 20.2°S, 57.5°E, 02 May 1965, J.R. Williams, 2 ♂♂ (00138689, 00138743) (AMNH). PAPUA NEW GUINEA:Eastern Highlands: No. 11, Arau, Kratke Mountains, Valley of the upper Wanton River, 12 Oct 1959, L. J. Brass, 1 ♂ (00138756) (AMNH). Morobe Province: Lae at head of Huon Gulf near mouth of Markham River, camp #1, 6.723°S, 146.991°E, 2 m, 07 Oct 1959 - 19 Oct 1959, L. J. Brass, 1 ♀ (00095355) (AMNH). South High Province: Upper Mendi, Hoai Village, 1970 m, 4-5 Nov. 1981, B. M. Thistleton, from sugarcane, 2 ♂♂, 1 ♀ (BMNH). PHILIPPINES:Luzon: Los Banos, 21 Nov 1921, F. X. Williams, sugarcane, 1 ♀ (00161942) (USNM). UNITED STATES:Hawaii:Honolulu Co.: Honolulu, Mar 1930, F.C. Hadden, 2 ♂♂ (00167072, 00167073) (CNC). Intercepted on ship at Honolulu port which originated from Treasure Island, California, 08 Mar 1939, R. G. Oakley, 1 ♂ (00162001) (USNM). Waialua, 22 Apr 1925, F. Muir, 1 nymph (00161928) (USNM); 22 Jan 1930, O. H. Swezey, 1 ♀ (00161919) (USNM). Waipio, 02 May 1923, O. H. Swezey, 1♀ (00161918) (USNM). Maui Co.: 2191 S. Kihei Road, 29 Feb 1984, G. M. Stonedahl, at mercury vapor light, 30 ♂♂ (00138660, 00138662, 00138666, 00138668, 00138672 - 00138673, 00138682, 00138693, 00138711, 00138745, 00138749, 00138754, 00138757, 00138760, 00138787, 00165832 - 00165846), 8 ♀♀ (00165847 - 00165854) (AMNH), 2 ♂♂ (00161944, 00161945) (USNM). Oahu Co.: Barber’s Point, Mar 1960, E. J. Ford, Jr., at light, 1 ♂ (00161947), 4 ♂ (00161952 - 00161954, 00161958) (USNM). Ewa Beach, 22 Nov 1982, collector unknown, 2 ♂♂ (00161949, 00161957), 2 ♀♀ (00161955, 00161956) (USNM). Honolulu, 21.3069°N, 157.8583°W, 35 m, 24 Feb 1943, N. L. H. Krauss, on corn plants, 1 ♀ (00161940) (USNM). John Rodgers [airport], May 1958, E. J. Ford, Jr., corn, 1 ♂ (00161941) (USNM). Kailua, 09 Oct 1930, O. H. Swezey, 1 ♂ (00161920) (USNM); 15 Sep 1950, T.H., feeding on corn leafhopper eggs, 1 ♂ (00161943) (USNM). Mokuleia, 05 Feb 1940, T. H., on green corn, 2 ♂♂ (00161950, 00161951), 1 ♀ (00161948) (USNM). Punloa, 21 Dec 1926, O. H. Swezey, 1 ♂ (00161922) (USNM). Waianae, 13 Jan 1931, O. H. Swezey, Taro, 1 ♀ (00161921) (USNM).