Thyanta (Thyanta) custator custator (Fabricius)

Rider, David A. & Chapin, J. B., 1992, Revision of the genus Thyanta Stal, 1862 (Heteroptera: Pentatomidae) II. North America, Central America, and the West Indies., Journal N Y Ent Soc 100 (1), No. 1, pp. 42-98 : 50-53

Thyanta (Thyanta) custator custator (Fabricius)

Figs. 16-30, Map 2

Cimex custator Fabricius, 1803: 164 .

Pentatoma custator: Dallas, 1851:251 ; Walker, 1867:288.

Thyanta custator: Stal, 1862a: 58 ; Stal, 1872:34-35 (part); Uhler, 1872: 399 (part); Uhler, 1876:289-290 (part); Uhler, 1886: 7 (part); Van Duzee, 1904: 53 (part); Kirkaldy, l 909:94 (part); Van Duzee, 1909: 155-156; Banks, 1910:90 (part); Barber, 1911: 108-111 (part); Barber, 1914: 523; Van Duzee, 1917: 52 (part); Blatchley, 1926: 113, 115-116 (part); Torre-Bueno, 1939:231 (part); Ruckes, 1957a:1-2, 4- 13, 20, 22, fig. l; Ueshima, 1963: 149, 152-153; Hoffman, 1971:44-45; Furth 1974:22, 23, fig. 45; McPherson, 1982:76-77, 80-81, fig. 73; Rolston and McDonald, 1984:figs. 24, 28; Froeschner, 1988:593.

Thyanta accerra (of authors, not McAtee): Blatchley, 1926: 114, 118.

Thyanta casta (of authors, not Stal): Blatchley, 1926: l 13, 116-117.

Diagnosis. Dorsal surface green to brown, often with varying amount of reddish coloration between humeral angles, sometimes extending along anterolateral pronotal margins and onto basal margin of each corium.

Lateral jugal margins sinuous, not parallel ( Fig. 17). Anterolateral margins of pronotum and mesial angle of each pronotal cicatrice piceous. Anterolateral pronotal margins slightly concave in dorsal view; humeral angles rounded to angulate, never spinose ( Fig. 16). Ventral surface yellow-green to brown, posterolateral angles of abdominal stemites black. Each abdominal sternite with postspiracular black spot on each side.

Mesial margins of basal plates nearly straight in caudoventral view; posterior margins sinuous; posteromesial angles narrowly rounded ( Fig. 28). Each posterolateral angle of pygophore continuing onto posteroventral surface as vague carina, forming rectangular impression; mesial portion of posterior margin slightly convex with small, V-shaped, emargination in middle in both ventral and dorsal views ( Figs. 25, 26); pygophore slightly concave in lateral view ( Fig. 27).

Types. The type specimen of Cimex custator is apparently no longer in existence ( Zimsen, 1964), and the original description does not adequately fix the species. Fabricius' description will fit either T. custator custator and T. calceata equally well. Previous usage, however, has fixed both species, and therefore the designation of a neotype is not necessary.

Distribution. Coastal plain from central Louisiana to Florida to New York, and the Bahama Islands ( Map 2).

Specimens examined. 1,243 specimens collected during every month of the year; deposited in AMNH, ARH, AUA, BMNH, CAS, CNC, cue, DAR, DBT, FMNH, FSCA, INHS, ISU, LHR, LSU, MSU, MSUE, NCSU, OSUC, PUL, SIUC, SMEK, TAMU, UAT, UCB, VCR, UCS, UGA, UIM, UMC, USNM, UUSL, WSU. UNITED STATES: Alabama: Baldwin , Barbour , Covington , Dallas , Escambia , Henry , Houston , Lee , Macon , Madison , Mobile . Florida: Alachua , Bay , Brevard , Broward , Charlotte , Clay , Collier , Columbia , Dade , De Soto , Dixie , Duvall , Franklin , Gadsden , Glades , Gulf , Hamilton , Hardee , Hendry , Highlands , Hillsborough , Holmes , Indian River , Jackson , Lake , Lee , Leon , Levy , Liberty , Madison , Manatee , Marion , Martin , Nassau , Okaloosa , Orange , Osceola , Palm Beach , Pasco , Pinellas , Polk , Putnam , St. Johns , St. Lucie , Santa Rosa , Sarasota , Seminole , Sumter , Suwanee , Taylor , Volusia , Wakulla , Washington . Georgia: Berrien , Brantley , Brooks , Charlton , Chatham , Clinch , Decatur , Evans , Glynn , Grady , Jefferson , McIntosh , Peach , Pierce , Sumter , Thomas , Tifton , Toombs , Ware . Louisiana: Acadia , Ascension , Avoyelles , East Baton Rouge , East Feliciana , Iberville , Jefferson , Livingston , Orleans , St. Charles , St. James , St. Mary , St. Tammany , Tangipahoa , Washington , West Baton Rouge . Mississippi: Covington, Forrest , Hancock , Harrison , Jackson , Jefferson Davis , Pike . New Jersey: Burlington , Cape May , Monmouth , Ocean . New York: Suffolk . North Carolina: Bladen , Brunswick , Columbus , Duplin , Hyde , Moore , New Hanover , Onslow , Pender . South Carolina: Aiken , Bamburg , Barnwell , Beaufort , Charleston , Florence , Greenville , Horry , Jasper , Kershaw , Marion , Orangeburg , Richland . Virginia: Norfolk . Bahama Islands: South Bimini Island .

Comments. This species has been the subject of much confusion in the past. At one time the name T. custator was applied to nearly all specimens from the entire United States. Ruckes (1957a) showed that the true custator form is confined to the coastal plain from Louisiana to Florida to New York, but he felt that it was a separate species distinct from the accerra form. The two forms have virtually identical genitalia. They cross-breed readily in the laboratory; and where their distributions overlap, specimens intermediate between the two forms are found fairly frequently. The two forms have a very narrow overlap in their respective ranges, however, and specimens taken from outside the area of overlap are usually easily identified. These two forms probably are more correctly considered subspecies.

Thyanta c. custator and T. calceata are the only two species in the genus with distinctly black anterolateral pronotal margins. They can be separated reliably from each other only by the characters of the male genitalia. The pygophoral opening in T. c. custator is subtended by a rectangular impression, while this impression is semicircular in T. calceata. When large series are present, some separation can be made based on the general shape of the body: T. custator is slightly longer and narrower than T. calceata. Fortunately, there is very little overlap in their distributions.