Schacontia lachesis Solis & Goldstein

Goldstein, Paul Z., Metz, Mark A. & Solis, M. Alma, 2013, Phylogenetic systematics of Schacontia Dyar with descriptions of eight new species (Lepidoptera, Crambidae), ZooKeys 291, pp. 27-81 : 64-67

Schacontia lachesis Solis & Goldstein sp. n. Figs 10, 1130, 3561-63

Material examined.

Type material. Holotype (♂, USNM) (Fig. 10): Brazil: Col. Becker 55439, Brasil: RJ Arrai al do Cabo, 50 m, 29.i.1985, V.O. Becker col. Paratypes 14 males, 11 females, USNM: Brazil: Same data as holotype (1♂, 1♀);Col. Becker 91635, Brasil: CE Pacatuba, 250 m, 6. iv. 1994, V.O. Becker Col. (1♂);Col. Becker 111257, Brasil: MT 60 km, S Poconé, 1-7.xii.1997, V.O. Becker Col. (1♀);Col. Becker 88540, Brasil: RO Cacaulãndia, 140 m, 15-18.x.1993, V. O. Becker Col. (1♀);Col. Becker 93888, Brasil: MT Chapada dos Guimarães, 800 m, 20.xi.1994, V. O. Becker Col. (1♀);Col. Becker 105713, Brasil: BA Jequié, 600-750 m, 11-22. xi.1995, V.O. Becker Col. (4♂, 1 ♀ and a disassociated male genitalic slide); Col. Becker 54553 Brasil: RJ Maricá, 5 m, 12-15.i.1995, V.O. Becker Col. (3♂, incl. 1 male w/white tag “Genitália 1259", 1♀). Bolivia: Santa Cruz, Puerto Suarez, 150 m, Nov 1908, J. Steinbach, CMNH Acc. 3758 (3♂, 1 abd. detached, prob. ♀); Santa Cruz, Provincia del Sara, 350 m, October 1911, Jose Steinbach, CMNH Acc. 5038 (2♀); Santa Cruz, Provincia del Sara, 350 m, Dec 1912, Jose Steinbach, CMNH Acc. 5038 (1♀); Santa Cruz, Puerto Suarez, 150 m, Dec 1908, J. Steinbach, CMNH Acc. 3758 (2♂, 1♀, dissection).

Diagnosis.

Habitus (Figs 10-11). A polymorphic species, some specimens resembling Schacontia rasa and Schacontia clotho in showing little to no ground color contrast between the variably mouse-gray or straw-colored medial area and the rest of the forewing; other specimens display a sharper contrast, with the medial area primarily gray and the antemedial and postmedial areas straw colored, very similar to some specimens of Schacontia atropos (below). Like most members of the genus (other than Schacontia rasa ; Table 1), Schacontia lachesis males bear specialized hind tibial scales, but like Schacontia nyx some specimens lack the dark patch embedded within them. Genitalia (Figs 61-63).Like those of Schacontia themis , Schacontia rasa , and Schacontia atropos , male genitalia of Schacontia lachesis have the uncus with raised or swollen edges, but do not share the other synapomorphies of the Schacontia themis -rasa pair and strongly resemble other members of the Schacontia nyx complex in bearing more elongate subcostal processes and ornate costae. Males of Schacontia lachesis are distinguished from those of Schacontia atropos (below), which they most closely resemble, by a combination of short coremata (Fig. 35), angled as opposed to rounded saccular bend (ulna), absence of a ventro-medial setal comb, and a more even distribution of ventro-marginal setae (Table 1).

Description.

(Figs 10, 11). Male. Forewing length: 5.0-7.5 mm. Head - Ocelli present; proboscis normal; frons of normal convex contour; labial palpi porrect, extending beyond clypeus. Thorax - Flattened hind tibial spur, specialized hind tibial scales, and epipleural setae present; female with two pair of hind tibial spurs (medial pair present); shallow concave metatarsal modification. Forewing. Prothoracic scaling tan gray, straw or yellowish. Forewing coloration equally variable, medial area polymorphic, exhibiting a range of contrast not known from other Schacontia , ranging from light to dark brown in both sexes, dusted with white; basal and postmedial areas straw colored; antemedial and postmedial lines jagged; orbicular spot faint but apparent; fringe scales darker at base; subterminal line unbroken. Hindwing. Postmedial line absent; fringe scales darker at base; subterminal line unbroken. Abdomen - Coremata on 4th abdominal segment (Fig. 35); scales arranged in two terminal black dorsal spots in males. Tympanal organs (Figs 30, 31). As for ysticalis-themis group, vide supra. Male genitalia (Figs 61, 62) - Teguminal sulcus short, such that anterior margin of tegumen appears deeply invaginate, two oblong teguminal lobes joined obliquely; lateral edges of uncus swollen, appearing reinforced; un cus trefoil-shaped tip reduced to a small, more or less rhomboid nipple; juxta U-shaped, tapered ventrally; valvae complex, intrasaccular flange transposed towards latero-ventral edge and sclerotized to form a trigger-shaped process; robust, spine-like setae at base of valva; saccular margin sharply angled at saccular mid-point; ventro-marginal setae distrib uted along length of outer margin of sacculus; valva with pronounced, elongate secondary outer lobe or process below costa; fleshy setose lobe and recurved/decumbent setal plume associated with terminus of costa; sharply hooked setal cluster prominent. Phallus moderately sclerotized; vesica with two large cornuti. Female genitalia (Fig. 63) - Papillae anales separate, unswollen; colliculum present, short, sclerotized, immediately posterior to corpus bursae, with narrow sclerotized band around center, sometimes separated from bursa by a sharp constriction; ductus bursae present, conspicuously sclerotized ventrally, entering corpus bursae dorsally; appendix bursae ventral, superficially complex; ductus seminalis attached at posterior end of ventral corpular out-pocketing.

Immature stages.

Unknown.

Etymology.

In Greek mythology, Lachesis is the middle sister of the three fates, the personification of destiny responsible for measuring the duration of human life. The specific epithet is treated as a noun in apposition.

Biology.

Unknown. Adults in Brazil active January, April, November, December; adults in Bolivia active October–December.

Distribution.

Central Brazil (Rondonia east to Bahia, Ceara and Rio de Janeiro), Bolivia (Santa Cruz).