Taxonomy, distribution, and food plants of Gyponana hasta, a leafhopper vector of California aster-yellows virus

Abstract does not appear. First page follows.

Introduction

Severin has previously reported (1934), (1940)4 that 3 species and a biological race of leafhoppers transmit the California aster-yellows virus. In two recent papers DeLong and (Severin (1945)) and (Severin (1945)) added 6 species of phlepsid leafhopper as vectors of this virus. The present paper deals with the characters, distribution, and food plants of one additional leafhopper vector, Gyponana hasta DeLong, in a companion paper, (Severin (1946)) discusses the transmission of the virus by this, the first reported leafhopper vector in the subfamily Gyponinae.

Characters, Distribution, and Food Plants

For several years Gyponana hasta, recently described (DeLong, 1942), has been confused with and identified as Gyponana angulata Spangberg, which it resembles very closely in general appearance and in morphologic structures.

Gyponana hasia is one of the few species of this genus with an angled vertex. This species is similar to G. anqulaia in general appearance, and can be distinguished from it only by the shape of the style and aedeagus. Its length is 7.5 to 9 mm.

The vertex is somewhat strongly produced and bluntly angled, and is two thirds as long at the middle as the basal width between the eyes.

In color it is somewhat variable, but usually is dull yellow with a tinge of green. The vertex, pronotum, and scutellum (plate 1, A and B) are often definitely yellow. There are no dark nor definite color markings.

The female last ventral segment has a posterior margin which is broadly, concavely excavated, with a slight median notch (plate 1, C).

The male plates are elongate, blunt at the apex, and with a slight bulge on the outer margin near the middle- (plate 1, D). The aedeagus (plate 1, E) is long and somewhat slender, with a pair of short terminal, lateral processes which extend about one third of the distance to the basal curved part and are closely appressed to the body of the aedeagus. The style is sickle-shaped, with the apical half broadened at the base, then gradually tapered to a sharppointed apex (plate 1, F).

In comparison with Gyponana angulata, the styles are longer and the tapered part is more slender before the apex. The aedeagus is longer, narrower, with shorter lateral processes which are more closely appressed.