Westindia Vincent

Westindia Vincent, new genus

Figs. 1–5

Type species: Westindia haxairei Vincent, new species by monotypy

Diagnosis. It proved impossible to associate the new species unequivocally to an already existing genus with the members of which it would share derived diagnostic characters. We describe here what we consider to be the main diagnostic features of this new genus. However, because we establish a monospecific genus, it is impossible to predict which ones of the unique characters described below may be potentially diagnostic at the genus level if other related species are discovered in the future. The higher placement of the new genus within Phaegopterina is assessed below. Westindia n. gen. can be distinguished externally from all other known Arctiinae by its wing pattern. The combination of an orange forewing with two ivory-white transverse bands and three longitudinal grey streaks, white hindwings and a wingspan greater than 50 mm is unique among the subfamily. Structurally the following combination of characters is diagnostic: hindwing with M2 strongly stalked with M3; male genitalia with a wrinkled scaphium and valves bifid characterized by a deep notch.

Description. Male (Fig. 1). Head. Labial palpi thin and strongly curved upward. First segment strongly curved upward. Second segment thinner, slightly curved and longer than the first. Third segment short and rounded. Proboscis longer than thorax with medium-sized sensillae at its tip. Eyes large without interfacetal setae. Ocellus present. Antennae with 87 flagellomeres, each bearing a pair of dorsal setae and a dense tuft of golden bristles ventrally. This tuft disappears progressively in the apical third. Thorax. Prothoracic legs with epiphysis foliate, apically acute, less than half the length of the tibia. Meso- and metathoracic legs with one and two pairs of tibial spurs, respectively; the spurs smooth, medium-sized and all equal in length. Tympanal Pocket IV present and closed ventrally. Metepisternal tympanal organ present and well developed. Patagia and tegulae developed and covered with long scales. Forewing. Elongate, narrow with apex acute. Venation is of the quadrifid type with M 3 in contact with M2; CuA1 and M3 are separate. Hindwing. Reduced and narrowed; its apex acute. Vein M2 strongly stalked with M3; Sc+R1 very thin where it reaches the costal margin. Abdomen. Large and tapered, entirely orange without distinguishable markings. Male terminalia (Figs. 2-3; 5-7). Eighth tergum rectangular, slightly sclerotized and prominent posteriorly. Eighth sternum trapeziform and as long as seventh sternum. Uncus and tegumen narrow and elongated. Tuba analis twice as wide as the tegumen at its base and extending beyond the apical end of the uncus. Scaphium sclerotized, concave and tongue-shaped (Fig. 5). Valvae short and symmetrical with a large notch separating two branches: one dorsal, with a very pointed tip, the other ventral ending with two digitiform processes (Fig 6). Vinculum thin with two membranous lobes at the articulation with the tegument (Fig 7). Aedeagus long and thin (5.4 mm), with vesica 5mm long and lacking cornuti (Fig 3).

Etymology. The generic name is derived from the West Indies (=Caribbean)