Phaselia Guenée, [1858]

Werner, Maria Johanna, Hausmann, Axel, Kostjuk, Igor, Wanke, Dominic & Rajaei, Hossein, 2023, Integrative taxonomic revision of the genus Phaselia Guenée, [1858] (Geometridae: Ennominae) in the Middle East and Central Asia, Zootaxa 5326 (1), pp. 1-66 : 5-9

Phaselia Guenée, [1858]

Phaselia Guenée [1858] : Histoire naturelle des insectes. Spécies général des lépidoptères IX, p. 228f. Type species: Synopsia phaeoleucaria Lederer, 1855 stat. rev. No genus synonyms.

Description. Wingspan. 24–43 mm, females slightly larger than males. Antennae bipectinate in both sexes. Head and thorax densely pale grey-brown scaled. Abdomen concolorous with head and thorax or dark brownish. Tibial spurs 0–2–2. Palpi short, proboscis reduced, barely visible.

Forewing. Costa slightly concave with well-curved outer margin; ground colour warm white, speckled with light to dark grey-brown tiny dots; basal area and postmedial area darker brownish than medial area; antemedial line dark brown, with strongly pronounced zigzag-shape with up to three peaks; medial line present as a diffuse darker brown shadow close to postmedial line; postmedial line thin, dark brown, S-shaped (medially curved outwards in the upper half, inwards at the lower half); subterminal line dark brown with triangular spikes and a white line as outer border; terminal line thin, dark brown and slightly wavy.

Hindwing. Ground colour white, speckled with brown towards terminal area; postmedial line brown, medially projected outwards, sometimes interrupted or even invisible; subterminal line barely visible as a light shadow; terminal line thin, dark brown and slightly wavy.

Discal spots usually visible as brown, short streaks or tiny dots on all wings, sometimes faded. Ventral side of wings generally paler than dorsal side, lines and patterns as on dorsal side but less pronounced. Fringes in all wings chequered white and brown, dark at the end of the veins (fig. 1).

Venation. In the forewing, vein Sc arising separately from the base of wing; R1 and R2 originating separately from cell and continuing to costal margin; R3–R4 on a common stalk, originating from the single areole (see fig. 2A), R3 ending at subapical part of costa, R4 ending at apex; R5 originating separately from areole (green colored in fig. 2); one single A vein originating from the base of wing. In the hindwing, vein Sc+R1 originating from base of wing, continuing parallel to cell, then medially strongly curved towards costa, ending at wing apex; A1+A2 originating separately from A3 (fig. 2).

Male genitalia. Uncus triangular, tip rounded, curved inwards; gnathos well-sclerotized, medially not fused; valva trapezoidal; costal part of valva slightly sclerotized, distally finger-shaped, extended over the apex of valvula; sacculus oval to square-shaped, well-sclerotized, mostly with diagnostic characters; juxta roughly triangular or horseshoe-shaped (fig. 3A). Aedeagus short, thick, straight or slightly curved; vesica with two separate, well-sclerotized cornuti: a claw-like curved cornutus and a more or less twisted, plate-like cornutus with numerous small spines (fig. 3B).

Female genitalia. Ovipositor large and wide, oval; length of apophyses varying slightly among the species; lamella postvaginalis well-sclerotized,narrow to wide; ductus bursae short, membranous;corpus bursae membranous, pear-shaped to oval, elongated; signum small, well-sclerotized and stellate, of variable shape (fig. 3C).

Diagnosis. Due to their characteristic wing pattern, Phaselia species cannot be confused with any other genera of the tribe Boarmiini .

Note. As the original descriptions of most Phaselia species are only superficial and genitalia characters were often left out, we provide a re-description part for all discussed species in this study.