Thyanta (Argosoma) straminea Rider, 1991

Thyanta (Argosoma) straminea Rider , new species

Figs. 352-356, Map 2

Description. Dorsal surface pale green, head and anterior disc of pronotum yellowish-brown, exocorium stramineous, apex of scutellum and apex of each humeral angle reddish; punctures pale brown.

Apex of head evenly rounded; outer jugal margins not quite parallel ( Fig. 353); surface transversely tumid, densely and evenly punctate. Anterolateral margins of pronotum in dorsal view concave; humeral angles acutely produced, nearly spinose, protruding beyond base of adjacent coria by more than width of eye ( Fig. 352). Pronotal disc uniformly punctate except punctures somewhat crowded anterior to cicatrices; pronotal cicatrices immaculate. Hemelytra rather sparsely punctate especially on distal fourth; posterior margins nearly straight; costal angles acute, reaching to anterior margin of last connexival segments; hemelytral membranes hyaline with a few faint brown flecks distally. Connexiva not exposed, pale yellow, posterolateral angles of segments black.

Ventral surface stramineous with greenish hues on head and propleura; punctures concolorous with surface. Rostrum stramineous with brown markings, distal half of segment 4 piceous, reaching onto base of abdomen. Apex ofhumeral angles reddish. Ostiolar canals acuminate apically. Femora and tibiae stramineous, tarsal segments and apex of each tibia brownish. Postspiracular spots vague, green; posterolateral angles of abdominal sternites piceous.

Mesial margins ofbasal plates in caudoventral view convex, separated basally and distally; posterior margins sinuous; posteromesial angles brown, weakly emarginate ( Fig. 354); surface of each basal plate punctate on mesial half. Distal end ofsclerotized rod slightly swollen subapically, narrowed apically ( Fig. 355); only small amount of swelling and coiling below proximal flange ( Fig. 356). Male unknown.

Measurements. Total length 7.57-8.28 (8.28); total width 5.68-5.96 (5.96); medial length ofpronotum 1.50- 1.81 (1.81). Medial length ofscutellum 3.46-3.64 (3.64); basal width 3.24-3.31 (3.31); width at distal end offrena 1.18-1.32 (1.32). Length ofhead 1.55- 1.59 (1.59); width 1.99-2.08 (2.08). Length of segments 1-5 ofantennae 0.40, 0.78--0.79 (0.78), 0.92-1.07 (1.07), 1.05-1.14 (1.14), and 1.10, respectively. Length of segments 2-4 of rostrum 1.23-1.29 (1.29), 0.70--0.75 (0.70), and 0.68- 0. 75 (0. 75), respectively.

Holotype. ♀ labeled (a) " Buenaventura Colombia '44 C. L. Fagan " (b) "Thyanta acutangula Jen-Har. det. H. Ruckes." Deposited in the American Museum ofNatural History (New York) .

Paratype. 1 ♀. " ECUADOR: NAPO PROVINCE, LIMONCOCHA, ON RIO NAPO 13 -XI-1973 BOYCE A. DRUMMOND, III BLACKLIGHT TRAP" (♀ USNM) .

Distribution. Colombia and Ecuador ( Map 2).

Comments. The acutely produced humeral angles and the stramineous-colored exocorium will easily identify this species within the subgenus Argosoma .

Etymology. Named for the stramineus-colored exocorium.