Thyanta (Argosoma) pseudocasta Blatchley Concave 1926
Creators: name: Rider, David A.
name: Chapin, J. B.
Publisher: name: Zenodo
Year: 1992
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Pentatomidae
Thyanta
Thyanta pseudocasta

description: Thyanta (Argosoma) pseudocasta Blatchley
Figs. 168-182, Map 9
Thyanta pseudocasta Blatchley, 1926:114, 120; Blatchley, 1930:64; Torre-Bueno, 1939:230; Rolston and McDonald, 1984:fi.gs. 26, 34; Froeschner, 1988: 594.
Thyanta casta (of authors, not Stal): Barber, 1914:523; Van Duzee, 1917: 53 (part); Torre-Bueno, 1939: 231 (part); Froeschner, 1988: 593 (part).
Diagnosis. General color pale green to pale brown, sometimes with anterior half of pronotum reddish.
Lateral jugal margins subparallel for middle third of distance from eyes to apex (Fig. 169). Anterolateral margins of pronotum nearly straight in dorsal view; humeral angles prominent, produced beyond base of adjacent corium by more than halfwidth ofeye, rounded to angulate (Fig. 168). Pronotal cicatrices immaculate. Ostiolar canals acuminate apically. Posterolateral angles of abdominal sternites piceous, sometimes only minutely so. Postspiracular black spots usually absent, sometimes present in brown form.
Basal plates in caudoventral view with mesial margins straight to slightly convex; posterior margins evenly convex, posteromesial angles rounded (Fig. 180). Sclerotized rod slightly swollen subapically, narrowed apically (Fig. 181); spermathecal duct with small amount of swelling and coiling below proximal flange (Fig. 182). Posterior margin of pygophore in caudal view broadly and shallowly U-shaped, slightly sinuous medially in caudal, ventral, and dorsal views (Figs. 176-178); pygophore emarginate in lateral view (Fig. 179). Apex of each paramere from ectal view nearly acute (Fig. l 71); from medial view narrowly rounded; concave surface facing mediad (Fig. l 70); roughened spiculate area on lateral surface circular (Fig. l 72). Aedeagus with each lateral conjunctival lobe apparently lacking sclerotized diverticula (Fig. 175); dorsomedial lobe apparently absent (Fig. 174); median penial lobes relatively small (Fig. 173).
Types. Blatchley (1926) described T. pseudocasta without designating a holotype or paratypes. In 1930, however, he designated 15 specimen as " type " (lectotype). He did not mention any of the other syntypes. Although actual paralectotype designations were not made, according to the International Code of Zoological Nomenclature (Ride et al., 1985, sect. 74a[iv]), once the lectotype is designated the remaining syntypes automatically become paralectotypes. Accordingly, no such designations are needed, but labels have been added to the specimens to indicate their actual status.
Regrettably, the d lectotype is in deplorable condition; all that remains is the head and pronotum. It has the following label data: (a) "Miami Fla. W. S. B. Coll. 3- 11 - 24 " (b) "Purdue Blatchley collection" (c) " TYPE " (d) " Thyanta pseudocasta Blatchley. " The lectotype is deposited in the Purdue University Collection (W. Lafayette, IN).
Ten additional specimens that are believed to be part of the original syntype series have been located: 15 and 2'i''i' labeled (a) "Miami Fla. W. S. B. Coll. 3- 11 -24 " (b) "Purdue Blatchley collection" (AMNH, PUL), except l'i' labeled (c) " Thyanta pseudocasta Blatchley " (LSU); 355 and 2'i''i' labeled (a) "C. Sable Fla. W. S. B. Coll. 2-23- 19 " (b) "Purdue Blatchley collection" (PUL), except 15 labeled (b) "H G Barber Colln1950" (USNM), and 15 and l'i' labeled " 4-5 -25 " (AMNH); 15 labeled (a) "K. West Fla. W. S. B. Coll. 3-2- 19 " (b) "Purdue Blatchley collection" (PUL); and 15 labeled (a) "Coxam Fla. W. S. B. Coll. 3-8 -21 " (b) "Purdue Blatchley collection" (LSU). The lectotype and all but one paralectotype were examined.
Distribution. Southern Florida (Map 9).
Specimens examined. 153 specimens collected during every month of the year; deposited in AMNH, ARH, CAS, CNC, CU, DAR, DBT, EGER, FSCA, LHR, LSU, MSU, PUL, SMEK, UCB, UCS, UGA, UMC, USNM. UNITED STATES: Florida: Caxambus. Broward: Fort Lauderdale. Charlotte: Charlotte Harbor Area, Little Gasparillo Island; Punta Gorda. Collier: Marco Island; Royal Palm Park. Dade: Biscayne Bay; Coral Gables; Homestead; Miami. Lee: Sannibel Island. Monroe: Big Pine Key; Cape Sable; Everglades Natl Park; Key Largo; Key West; Marathon Key; Plantation Key; Stock Island; Tavernier Key; 9 mi NW Key Largo.
Comments. Thyanta pseudocasta can be separated from all congeners except T. maculata because the concave surface of its paramere is oriented more mediad than dorsad. Thyanta pseudocasta may actually be a subspecies of T. maculata. The male genitalia of the two species are very similar, but there are some differences in the aedeagus. Thyanta maculata has a prominent dorsomedial conjunctiva! lobe, while this structure is apparently absent in T. pseudocasta. Also, the humeral angles are more prominent in T. pseudocasta. Because these species represent reproductively isolated populations, a conservative approach is taken, and they are retained as full species.
description: Published as part of 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., pp. 42-98 in Journal N Y Ent Soc 100 (1) on pages 86-89