A N E W SPECIES OF EMPOASCA WALSH (HOMOPTERA; CICADELLOIDEA) ATTACKING TEA IN ARGENTINA.

By M. S. K. GHAURI,

Commonwealth Insti tute of Entomology, London.

THE following description is based on several specimens of a new species of Empoasca Walsh (1862 a) submitted by Seignior Pablo Navajas Artaza, Director, Establecimiento Las Marias, S. A. Gobernador Virasoro, Argentina. Seignior Artaza informs the writer that the species is certainly common in Northeastern Argentina and that the damage caused by it to plucking tea is quite serious, though the infestation is patchy; as a result the plants practically stop flushing, and the damage becomes visible when the tender shoots turn brownish instead of their normal green and the new growth slows down or appears warped. The population of pest on infested plants is very heavy and concentrated on buds, veins of leaves and tender stalks. The damage to tea by Empoasca is experi- enced for the first time in this area, according to Seignior Artaza. The help of Seignior Artaza who supplied the material and information about the activities of the new species, is gratefully acknowledged.

The abbreviated references quoted in this article are according to the Bibliography of the Cicadelloidea (Homoptera: Auchenorhyncha) Fasicle VI, March, 1964, by Z. P. Metcalf.

Genus EMPOASCA Walsh (1862 a). Type of the genus Empoasca viridescens Walsh (loc. cit.).

Empoasca paraobliqua sp. n. The new species runs to Empoasca muricata Caldwell in the key to the

species of Empoasca of Puerto Rico (Caldwell and Martorell, 1952 a, p. 117), bu t differs from it in the shape of the anal tube process (dorsal spine) which unlike that of the old species, is strongly curved and sickle- shaped. In this character the new species closely resembles Empoasca obliqua Caldwell (ibid. p. 127), but differs in the shape of the superior style (lateral process, brachone or pygofer process) which unlike that of obliqua, is much longer than the pygofer and upturned apically. The new species does not resemble any of the species described and included in the Argentina leafhoppers of the genus Empoasca by Young (1953 b) or by Torres who described two new species of Empoasca from Argentina in 1955 (pp. 299-302) and 1959 (pp. 65-69), respectively. On the whole it seems to be closely related to Empoasca obliqua Caldwell. Unfortunately, no specimen of the latter species was available to the writer for a com- parison, but thanks to Dr. J. P. Kramer of the U.S. National Museum,

190 M. S. K. Ghauri : A new species of Empoasca from Argentina

Washington, who very kindly compared the new species with the type of obliqua, the following differences were found sufficient to separate these species:

E. paraobliqua E. Obliqua

Anal tube process Very wide Slender

Superior style Gently up turned apically Straight and shorter t han and longer than pygofer pygofer

Paramere Same as in obliqua Finely serrated ventral ly and distally

Aedeagus As il lustrated No significant difference

For the above table and for other information contained in Dr. Kramer 's personal letter to me, I take this opportunity to thank him for his assistance.

Body slender, elongate, delicate and shining. Colour. Shining, general body colour bright yellow suffused with

bluish green. Eyes brown. Tegmen bright yellow tinged with green and with colourless hyaline streaks; wings hyaline, veins light pale yellow. Legs--apex of femora, tibiae and tarsi heavily tinged with bluish green, claws brown. Ovipositor concolorous with the rest of the body.

Structure. Vertex longer medially than next to eye, rounded anteriorly, wider between eyes than median length. Pronotum more than one and a half times longer than head, anterior margin convex, posterior shallowly concave, more than one and a half times as wide at base as length in middle. Scutellum as long as pronotum, wider at base than length, with transverse suture distinct. Tegmen extending well beyond apex of abdomen.

Male genitalia and abdominal apodemes. Pygofer with few small setae, arranged in three irregular rows near posterior margin; superior style (brachone, pygofer process or lateral process) longer than pygofer and gently upturned apically, without setae, apex narrowed; subgenital plates large, upturned, basal area and lower margin with strong macro- setae, upper apical margin with small short setae, middle area and proxi- mate upper margin provided with thin long setae, very long thin set~e located variously, especially near lower apical margin. Anal tube, long and sclerotized, anal tube process (dorsal process) very wide in middle, curved downward and backward, sickle-shaped; basal plate (connective), roughly triangular with broad apex; paramere (style, inferior style or harpagone), with apex curved, convex margin with teeth, concave margin with a few small setae; mdeagus with curved base and apical projection for joining base of anal tube. Tergal apodemes, with bases widely separated; other apodemes as illustrated.

M. S. K. Ghauri : A new species of Empoasca from Argentina 191

Fig.

H

~ s j

Empoasca paraobliqua sp. n. A, head and thorax of male, dorsal view; B, tegmen; C, wing; D, pygofer with anal tube,

lateral view; E, subgenital plate, lateral view; F, basal plate (connective), dorsal view; G, paramere (style), dorsal view; It, ~edeagus, lateral view; I, base of abdomen of male, showing tergal apodemes; J, the same, showing sternal apodemes; K, sternite vii of female.

192 M . S . K . Ghauri: A new species of Empoasca from Argentina

Female VII sternite with posterior margin almost straight. Measurements in ram. Head, width 0.64 (female, 0.68); vertex,

median length 0.2, width 0.27 (female, 0.34). Pronotum, length 0.34, width at base 0-61. Scutellum, length 0.34, width at base 0.42. Tegmen, 2.23 (female, 2.37). Total body length up to apex of tegmen, 2.8 of male and 3.0 of female.

Holotype male, several male and female paratypes, Argentina, Gobernador Virasoro, April-May, 1964, Seignior Pablo Navajas Artaza, Director, Establicemiento Las Marias S.A. Gobernador Virasoro, on tea (Camellia sinensis L.), deposited in the British Museum (N.H.), London; one paratype male and one paratype female in the U.S. National Museum, Washington D.C., U.S.A.

Remarks. The new species is named E. paraobliqua because of its strong resemblance to E. obliqua Caldwell, but it can be readily distin- guished from the latter by the length of the superior style which is upturned and extends beyond the posterior margin of the pygofer and the wide anal tube process. These differences can be seen by a comparison of the figures provided in this article with those by Caldwell (Caldwell and Martorell, 1952, p. 129).

Summary. A new species of Empoasca attacking tea in Argentina is described and compared with Empoasca obliqua Caldwell.

I:~EFERENCES.

CALDWELL, J . S. ~5 MARTORELL, L . F . 1952. J . At t ic . Univ. P .R . Rio Piedras, 34, 1-132. To:aRES, B . A . 1955. Notas Mus. La Plata Zool. (164), 18, 299-302.

1959. Neotropica (18), 5 (A), 65-69.