Grotella blanchardi McElvare 1966

Grotella blanchardi McElvare, 1966, Jour. Lep. Soc., 20: 91, text figure adult.

Diagnosis: Grotella blanchardi is one of the largest species of Grotella and is characterized by a white forewing with black spots representing the antemedial, postmedial, and terminal lines. The forewing is white with a very slight yellow tint but appears much whiter than margueritaria. The upper half of the basal line is represented by two black dots. The antemedial line consists of four black dots and the postmedial line of five. The second from the top dot of the antemedial line projects outward from the others giving the antemedial line a triangular projection. This projecting black dot may be the orbicular mark, but I cannot be sure. A black linear dot exists along the costa between the antemedial and postmedial lines. The reniform mark is absent. The postmedial line consists of a single row of black dots. The line is nearly straight and is not curved inwardly below the position of the reniform. The subterminal line consists only of two black dots near the costa. The outer margin of the wing is marked by a series of strong black dots. The hindwing postmedial line is present in almost all specimens and the outer margin is commonly suffused with gray-brown to a variable degree. The male valve is short and rectangular and the costal margin is produced into a spine at its apex. The juxta possess as triangular projection. The lower group of smaller spine-like cornuti in the vesica has few spines in it and the group is diffuse, not concentrated into a distinct group. A small ventral (in the orientation of the figure) diverticulum is present. The female genitalia are basically the same as in most species of the species group. However the appendix bursae does not bend to the left as it does in the other species and it is composed of two lobes and is slightly convoluted in general. The origin of the ductus busae is borne on a short, globular diverticulum. The corpus bursae is relatively short compared to other species in the group, about three times longer than wide.

Adults have been collected in August, September, and October.

Distribution: Grotella blanchardi occurs in southwestern Texas, southern and central New Mexico and southeastern Arizona. The species is also known from scattered localities in northern Mexico. The intensity of the black dots on the forewing is variable, in particular the black dots along the outer margin. The amount of black shading in the hindwing is variable. In some specimens the hindwing is nearly all white, but in others the black suffusion may be very strong in the outer half of the wing. All possible intergrades exist.

Identification Quality: Excellent

Larva: Unknown

Foodplants: Unknown

Similar Species

Grotella binda