Tosta pseudospeculum Siewert, Mielke & Casagrande

Siewert, Ricardo Russo, Mielke, Olaf Hermann Hendrik & Casagrande, Mirna Martins, 2015, Tosta Evans, 1953 (Lepidoptera: Hesperiidae): a new species from northeast Brazil, first description of the female of Tosta tosta Evans, 1953, and placement of the genus within Achlyodini, Zootaxa 3999 (3), pp. 446-450 : 446-447

Tosta pseudospeculum Siewert, Mielke & Casagrande sp. nov.

( Figs 1–4 , 9–13, 19–20 )

Diagnosis. Tosta pseudospeculum sp. nov. resembles most Tosta tosta Evans, 1953 but can be distinguished by its wider wingspan, the darker upperside wings with bands less marked than in T. tosta , ampulla separate from harpe and highly modified in a process with the distal portion dilated and serrated, and lamella antevaginalis with two spine-like well sclerotized projections extending laterally.

Description. Head: entirely dark brown; eyes glabrous, brown; labial palpus with mixed brown and dark gray scales, porrect; antennae dark brown, nudum with 27–28 segments (n=4).

Thorax: dorsally dark brown, ventrally brown; legs brown.

Forewing: male 24–25.5 mm (Holotype 25 mm), average length = 25 mm (n=3); female 26 mm (Allotype). Upperside ( Figs 1 and 3 ): ground color dark purple-brown; basal, discal and postdiscal bands dark brown extending from costa to anal margin; submarginal area lighter than ground color; no costal fold. Female as in male, but lighter and with bands more evident. Underside ( Figs 2 and 4 ): ground color dark brown, paler distally; pale brown speculum covering about one-half from anterior portion of discal cell to anal margin and extending until two-thirds to tornus with a tuft of dark long hair-like scales originating from the base of the wing.

Hind wing: costa modified, resembling a hump that covers the forewing speculum. Upperside ( Figs 1 and 3 ): ground color dark purple-brown. Underside ( Figs 2 and 4 ): ground color dark brown; discal and postdiscal bands darker. Female as in male, but lighter and with bands more evident.

Abdomen: dorsally dark brown, ventrally brown. Female with no gland at 7th tergite.

Male genitalia ( Figs 9–13 ): uncus triangular dorsally, curved ventrally, with two dorsal projections; tegumen squared dorsally; valva squared, ampulla separate from harpe and highly modified in a process with the distal portion dilated and serrated, harpe with a spine-like process curved inwards; aedeagus cylindrical, coecum thin and slightly bilobed, a group of small spines at the distal end of aedeagus, cornuti absent.

Female genitalia ( Figs 19–20 ): eighth tergite rectangular; papilla analis with postapophysis about the same length as the ductus bursae; sterigma formed by a a lamella antevaginalis with two well sclerotized projections extending laterally and by a broad and rectangular lamella postvaginalis; ductus and corpus bursae totally membranous.

Etymology. The specific epithet refers to the superficially similarity with Speculum speculum Austin, 1998, a recently described genus and species from Rondônia, Brazil.

Distribution. This species is currently known from Maranhão and Roraima states, Brazil, but it should also occur in other areas of the Amazon, such as Pará and Amazonas states, Guyana, Suriname and French Guiana.

Type material. Holotype male with the following labels (separated by oblique bars): / HOLOTYPUS / Tosta pseudospeculum Siewert, Mielke & Casagrande det. 2014/ Faz[enda] Terrasse, Km 108 estr. Açailândia-St.Luzia, Sta. Luzia, MA[ranhão, Brazil]. 4-VIII-1974 Mielke leg./ DZ 15.982/. Deposited in DZUP. Allotype female with the following labels (separated by oblique bars): /ALLOTYPUS/ Tosta pseudospeculum Siewert, Mielke & Casagrande det. 2014/ Faz. Terrasses, Km 108 estr. Açailândia-St.Luzia, Sta. Luzia, MA[ranhão, Brazil]. 2-VIII-1974 Mielke leg./ GEN. PREP. R. SIEWERT/ DZ 30.917*/. Deposited in DZUP.

Paratypes. BRAZIL— Maranhão: Santa Luzia— Fazenda Terrasses, Km 108, estrada entre Açailândia-Santa Luzia, 1 male, 4-VIII-1974, Mielke leg., DZ 30.918 ( DZUP). Roraima: Uiramutã— Maloca da Serra do Sol, 1 male, 18- IX-1979, Gifford leg., DZ 3.923* ( DZUP).

Figures

FIGURES 1 – 8. Species of Tosta Evans, 1953. 1 – 4. T. pseudospeculum sp. nov.; 1 – 2. Male holotype, dorsal and ventral; 3 – 4. Female allotype, dorsal and ventral; 5 – 8. T. tosta Evans, 1953; 5 – 6. Male from Santa Luzia, Maranhão, Brazil, dorsal and ventral; 7 – 8. Female from Santa Luzia, Maranhão, Brazil, dorsal and ventral. Scale bar = 1 cm.

FIGURES 9 – 22. Genitalia of species of Tosta Evans, 1953. 9 – 13. Male genitalia of T. pseudospeculum sp. nov.; 9. lateral; 10 – 11. aedeagus, dorsal and lateral; 12. uncus and tegumen, dorsal. 13. right valva, internal view. 14 – 18. Male genitalia of T. tosta Evans, 1953; 14. lateral; 15 – 16. aedeagus, dorsal and lateral; 17. uncus and tegumen, dorsal. 18. right valva, internal view. 19 – 20. Female genitalia of T. pseudospeculum sp. nov.; 19. lateral; 20. ventral view of stergima. 21 – 22. Female genitalia of T. tosta Evans, 1953; 21. lateral; 22. ventral view of sterigma. Scale bars = 1 mm.