Characters, distribution, and food plants of newly discovered vectors of California aster-yellows virus

Abstract does not appear. First page follows.

Introduction

Five leafhopper species are reported in the accompanying paper (Severin, 1947)5 as vectors of California aster-yellows virus. The insects are illustrated by colored plates in that paper. The present paper deals with the characters, distribution, and food plants of these leafhopper vectors, which belong to the genera Cloanthanus, Euscelis, Fieberiella and Chlorotettix.

Cloanthanus Aculus (Say)

Cloanthanus acuius has not been demonstrated to be a vector of the virus, but is included here because it has been confused with other species.

The species of Cloanthanus, formerly placed in Platymetopius, have been confused in their identity for many years because an attempt has been made to determine them by color pattern alone. These species unfortunately are too similar in color to distinguish several of the common species on this basis.

After a study of the Mexican and southwestern species, (DeLong (1943)) used the male genital structures to distinguish them. He showed that in many cases the structures are quite different. By means of those structures he set up a neotype (1945) for one of the common eastern species, Cloanthanus acutus(Say, 1831) illustrating the genital structures (fig. 1) and describing several closelyrelated species in the East. From these studies it is obvious that several common or economic species have been erroneously identified in the past, and it is apparent that typical C. acutus does not occur in California nor the western United States in general.

Cloanthanus Irroralus (Van Duzee)

Cloanthanus irroratus(Van Duzee, 1910) is a brown species with a banded vertex and an irrorate face. In length it measures from 3.5 to 4.0 mm.

The vertex (fig. 2, A) is strongly produced and angled, and its median length is a little more than one third greater than the basal width between the eyes.

In color the vertex is dark brown with a wedge-shaped apical spot. A series of short pale longitudinal lines form a broken transverse band before the eyes. The base is also pale. The pronotum is brown with five pale longitudinal lines.