Achagua velata Matson 2023, n. sp.

Achagua velata Matson, n. sp.

(Figs. 4, 8, 11, 12)

LSID: 0E4A82F4-6BDF-43BE-86F8-572966809E46

Diagnosis. The following diagnosis is based on information from a single individual of A. velata, and caution should be exercised when interpreting it. As of now, Achagua velata is currently the only member of the genus known to inhabit the Guianan moist forests of northeastern South America. This species bears a conspicuous antemedial black spot along the forewing inner margin and a weakly gray, discal, reniform spot that are absent in both A. magna and A. obsoleta. The terminal band on both wings is thicker and more complete than in other congeners. The male genitalia of A. velata lack a spatulate dorsal process of the uncus, a postmedial digitate protuberance on the costa, and cornuti on the vesica, all of which are found in A. magna and A. obsoleta. While male A. velata shares many genitalic similarities with A. cooperae, the dorsal process of the uncus appears knob-like in A. cooperae (Fig. 7a), whereas in A. velata (Fig. 8a), it is more uniform in shape. Achagua velata and A. cooperae may also be separated by their COI barcode (see Molecular characterization).

Description. MALE. Forewing length, 17 mm (n = 1).

Head. Antenna mostly bipectinate, but with gradually diminishing rami that are absent in distal third of antenna; scales above white and light gray, rami dark gray to black. Vertex white; frons mostly light gray. Labial palpus short, decumbent, 1.5x diameter of eye, light gray and white. Chaetosemata in transverse row.

Thorax. Patagium, tegula, and mesothorax admixture of gray and white scales. Legs mostly white and mottled with gray; epiphysis well-developed; hind tibia with hair pencil (not easily visualized in holotype); tibial spur formula 0–2–4.

Forewing. Pearly-white; widely scattered with inconspicuous light gray scales. Basal and costal areas lightly maculated with gray to brown scales. Subtle, light gray, transverse antemedial line, and weakly gray, discal, reniform spot. Inner margin with antemedial black spot. Terminal area broadly maculated with brown scales. Underside patterned as in upperside, but darkened areas more diffuse and given more toward black.

Hindwing. Pearly-white except for complete, broadly dark brown outer margin. Underside patterned as in upperside.

Abdomen. Admixture of gray and white. Third sternite of male abdomen with comb of setae.

Genitalia (Fig. 8). Uncus abruptly widened at base; dorsal and ventral processes thumb-like. Base of gnathos subquadrangular, with upcurved, heavily sclerotized, pointed apical projection; projection lightly papillated. Valve elongate and large with heavily sclerotized costa; apex strongly falcate. Anellar processes large and triangulate, directed inward, and with apical recurved hooks. Juxta with medial, long cylindrical process with acuminate apex. Vesica with small medial sclerotized patch; cornuti absent.

FEMALE. Unknown.

Type Material.

Holotype

FRENCH GUIANA [FRANCE] • ♁; Régina, Nouragues Nature Reserve; (4.096°, -52.683°); elev. 419 m; 09 Jul. 2010; Carlos Lopez-Vaamonde leg.; Genitalia: TAM-2023-289; BOLD Process ID: LNOUD2050 -12; MNHN.

Distribution (Fig. 11). Presently, A. velata is only known from the Guianan moist forests at the type locality in French Guiana.

Biology. Immature stages and host associations remain unknown. Adults are known to fly in July at the type locality.

Etymology. The specific epithet velata is derived from the Latin “velatus,” meaning “veiled.” The name was chosen because of the rarely seen nature of this species—thus far only known from a single individual—and for its white, wedding-veil-like ground color.

Molecular characterization. Achagua velata is represented in BOLD by the BIN: BOLD:ABV2454 (n = 1). The pairwise distance to the nearest neighbor, Achagua cooperae (n = 5, Costa Rica), is about 3.8%.