Thalleulia bisexta Brown, 2022

Thalleulia bisexta Brown , new species

LSIDurn:lsid:zoobank.org:act: 0ACDDA61-B36C-4602-9D73-A7E79FC23663

( Figs. 1‒3 View FIGURES 1‒3 )

Type material. Holotype ♂, Costa Rica, Cartago, P.N. Tapanti, Sect. La Repressa, 300 m SE del Puente de Rio Porras, 1660 m, Oct 1998, R. Delgado ( MNCR-A) . Paratypes (14♂, 7♀). Costa Rica: Cartago: Monumento Nacional Guaybo, Turrialba , 1100 m, Sep 1994 (2♀), Nov 1994 (1♀), G. Fonseca ( MNCR-A) . P.N. Tapantí-Macizo de la Muerte, Paraiso, Sect. Repressa 300 m SE Puente de Río Porras, 1660 m, Oct 1998 (1♂), Jun 2001 (1♂), Aug 2001 (1♂), Nov 2001 (1♂), Aug 2002 (1♂), R. Delgado ( MNCR-A) . P.N. Tapantí, El Guarco, San Ysidro, Est. Esperanza , 2600 m, May 2001 (1♀), R. Delgado ( MNCR-A) . El Guarco, Villa Mills , CATIE, 2840 m, 26‒28 Oct 2000 (1♂), R. Delgado ( MNCR-A) . Heredia: 9 km NE Vara Blanca, Finca Murrillo , 1500 m, 8 Apr 2005 (1♂), K. Nishida, 5‒13 Apr 2005 (1♂), INBio-OET-ALAS transect ( MNCR-A) . Calle Ziriqui, 1.5 km E Porton Municipal, San Ysidro, St. Elena , 1500 m, 31 Jul 2006 (1♂), J.B. Sullivan ( USNM) . Puntarenas: Las Cruces, nr. San Vito , 19‒20 Mar 1965 (2♀), S.S. & W.D. Duckworth ( USNM) . A.C.L. A.P., Coto Brus, Z.P. Las Tablas, Est. Biol. Las Alturas , 1500 m, 15‒24 Mar 1999 (2♂, 1♀), R. Barton, G. Rodriguez & R. Delgado ( MNCR-A) . Monteverde , 25‒28 Jun 1979 (1♂), D. H. Janzen ( MNCR-A) . San José: Est. Cuerci, Sendero al Mirador , 4.6 km E Villa Mills, 2640 m, 19‒20 Apr 1996 (2♂), A. Picado & B. Gamboa ( NMCR-A) .

Diagnosis. Thalleulia bisexta is superficially most similar to T. pondoana from Ecuador, with a somewhat uniform brown forewing lacking distinct pattern elements. Thalleulia bisexta can be distinguished from T. pondoana and other congeners by the presence of dense, transverse, slender striae throughout the forewing ( Fig. 1 View FIGURES 1‒3 ). The male genitalia of T. bisexta ( Fig. 2 View FIGURES 1‒3 ) are nearly identical to those of T. gracilescens , but they can be distinguished by the slightly straighter sacculus (weakly undulate in T. gracilescens ), a hooked tip at the apex of the lateral process of the gnathos (slightly curved in the distal 0.2 in T. gracilescens ), and a more uniform coverage of granulation on the vesica.

Description. Head: Vertex dark rust, lower frons pale orange-ocherous; labial palpus pale rust laterally, cream on inner surface; antenna with rust scales basally, paler distally. Ocellus tiny. Chaetosemata present. Thorax: Nota and tegula dark rust. Forewing length 7.0‒10.0 mm; forewing ( Fig. 1 View FIGURES 1‒3 ) ground color pale cream, densely overscaled throughout with narrow, rust, mostly interrupted, transverse striae, usually with a single, slender, complete arched stria from postmedian costa to tornus and a slightly more concentrated region of scales just basal to end of discal cell; fringe rust-brown in termen, paler throughout tornus. Hindwing white with faint, pale tan overscaling, densest at outer 0.15; fringe pale cream-tan. Abdomen: Scaling pale cream-tan. Male genitalia ( Fig. 2 View FIGURES 1‒3 ) with uncus slender, rodlike, broadest basally; socius broad, pendant, membranous, with long fine setae, from a narrow, rounded stalk, creating appearance of a pair of sublateral humps; gnathos arms joined distally into long, slender, spine-like process, each arm with long, straight, free, latero-terminal process, broadest subbasally, attenuate distally, with hooked tip; transtilla a weakly sclerotized band with weak dorso-median lobe; valva broad, parallel sided, rounded apically, weakly upcurved, costa weakly sclerotized, a series of slightly oblique, parallel wrinkles in basal 0.5 (not associated with fine hairs from venter of valva), sacculus narrow, sclerotized, restricted to basal 0.5 of valva, ending in a free terminal tip; phallus relatively straight, broad, rounded at base, with a pair of slender, lateral, wing-like processes, vesica with a small patch of tiny, non-deciduous cornuti and large areas of fine granulation. Female genitalia ( Fig. 3 View FIGURES 1‒3 ) with papillae anales and apophyses unmodified; lamella postvaginalis a broad lateral plate with three or more, wrinkly, nearly parallel lines extending outward from median ovoid region; lamella antevaginalis a broadly Vshaped cup, truncate at anterior margin, with rounded excavation at posterior margin; ductus bursae short, stout, not differentiated from corpus bursae; origin of ductus seminalis undetermined; corpus bursae elongate-oblong, with a single long, subcylindrical signum bearing irregular rows of long slender spines. A single spermataphore present in one dissection.

Distribution and Biology. Thalleulia bisexta is known from the Costa Rican provinces of Cartago, Heredia, Puntarenas, and San José. Specimens have been collected mostly between 1000 and 1600 m elevation; three specimens from 2600‒2840 m are slightly larger than those collected at lower elevations. Specimens have been captured nearly throughout the year: March, April, May, June, July, August, September, and November. The early stages are unknown.

Etymology. The specific epithet refers to the fact that this species is represented by both males and females —the first species of the genus to be so.