A New Species of Erythroneura (Typhlocybinae, Hem.-Hom.) from Arundo conspicua Forst. (Toetoe)
[Read before the Wellington Branch, March 15, 1951; received by the Editor, March 15, 1951]
Myers (1923) desribed four species of Erythroneura — namely, E. ansonae, E. cyathea, E. kiekie and E. zealandica. No further species from New Zealand appear to have been described. The present species was discovered in 1949 while studying the insects in swamp areas.
Myers, in describing the above species, used the genius Erythroneura in preference to the genus Typhlocyba because in the latter genus … “the fourth apical vein of the tegmen curves to the radial margin, and the second apical cell is triangular and usually stalked, while in Erythroneura (sens. strict.) the fourth apical vein of the tegmen runs parallel to the radial margin and ends in the apical margin, the second apical cell being more or less oblong and based directly on the cross-vein. Examination of a very large series of New Zealand specimens has shown this to be a perfectly constant character so far as our species are concerned, and it has consequently been adopted in this paper. Should further study demonstrate instability in this venational character all-the species I have described under Erythroneura must be placed in Typhlocyba, which will then have the complete synonomy given above.” The venation of the present species clearly conforms with that described above for the genus Erythroneura.
Erythroneura toetoe n. sp. (Figs. 1–4).
General colour, light yellow dorsally, and pale lemon ventrally. Eyes a little paler than the dorsal surface and in the living specimen with a small dark central dot showing through from within. In the killed specimen the greater part of the interior of the eye darkens and is visible through its outer pale surface. Vertex light yellow, scarcely convex between the eyes, produced, with a median suture distinct at the posterior margin. Length of head about three-quarters posterior width between the eyes (scale 1 mm. = 90 units, 24:34). Pronotum yellow, shiny, only moderately convex, width about twice median length and less than width of head across eyes (scale 1 mm. = 90 units. 60:32:67); with a smooth anterior collar-like portion, the remainder with fine transverse striations and a few scattered, centrally placed, circular punctations. Base deeply excavated, the sides of the emargination very slightly sinuate, basal angles broadly truncate, with postero-lateral margins straight; sides behind eyes nearly straight and parallel. Scutellum yellow, broader than the base of the vertex, not nearly so wide as head across eyes (scale 1 mm. = 90 units; 45:34:67), posteriorly acute and slightly raised. The meta-tergum shows some darkening, especially on either side of the
midline, and posteriorly. The abdominal segments of the female are slightly darkened dorsally, especially on their anterior margins, this darkening being more pronounced in the dead specimen. This pigmentation is absent or only very slight in the male. Length to end of abdomen, 2.4–2.9 mm. Tegmen yellow, with pale milky margins; costal plaque pale; wing milky. Tarsal claws in all legs, darkened.
Total length 3.5–3.9 mm., the male being slightly smaller than the female.
This species has been collected from Toetoe (Arundo conspicua) and possibly is restricted to this plant, where it occurs in moderately
large numbers. Adults and nymphs are present at all times of the year, although they are more numerous during the summer months. The newly emerged nymphs have been observed in October.
Paiaka swamp area, between Shannon and Foxton.
Described from a series of 10 males and 10 females.
Holotype, allotype, and paratypes in the collections of the Dominion Museum, Wellington.
fig. 5 shows the eggs of E. toetoe seen when the leaf is split open along the line of oviposition. Eggs (1–3, usually 2) are deposited in pockets about 2 mm. apart, and forming series of up to a dozen pockets. Ovoposition takes place on the upper surface of the blade and often adjacent to the thicker central region. The upper surface of the blade usually comes to lie lowermost as the blade approaches its full length. The eggs appear to be parasitized in some instances by a Hymenopterous insect.
This species differs in several characters from the four described by Myers. The tegmina are acutely angled apically—not rounded as in the other species. (This character might be used to expand Myers’ key, page 424, where under “3” it may be distinguished from E. zealandica and E. cyathea.) The claspers differ in shape in their greater expansion distally. The genital styles also differ in shape from those pictured by Myers for E. cyathea, E. kickie, and E. zealandica. These differences are illustrated in the figures.
Dr. T. E. Woodward, Zoology Department, Auckland University College, gave useful suggestions for the description of the species, and Mr. R. T. J. Blick, of Cawthron Institute, Nelson, kindly photographed my figures.
Myers, J. G., 1923. A Contribution to the Study of New Zealand Leaf-hoppers and Plant-hoppers (Cicadellidae and Fulgoroidea). Trans. N.Z. Inst., vol. 54, pp. 407–429.