Explanation of Names
Platycotis vittata (Fabricius 1803)
Grayish spotted with yellow, or turquoise with red stripes and red eyes. With or without a thorn-like horn.
This species may be easily distinguished from all our other species of membracids (except Umbonia and Lephopelta) by its very short posterior tarsi. It usually has a long compressed pronotal horn which varies greatly in length and may be entirely absent. The wing venation shows considerable variation. Green body color, mottled or speckled with orange. (Dozier 1920)
Hornless and horned variants:
mostly e. US and BC to s.Calif., plus limited AZ-NM records / Mex. - Map (1)(2)
Forests and forest edges, parks, and anywhere Oak trees are found. Occasionally found on other trees, but these individuals were probably just resting on those non-Oak trees.
Fairly common on deciduous and evergreen oaks, Quercus spp.
Hatching occurs in Spring in the South, and in late Spring in the North. Larva pass through five instars, and adults and larva form aggregations along oak twigs of up to 100 individuals. Females seem to exhibit protective behavior, keeping predators away from the young.
Does almost no damage to the host trees—leaves only a few twig scars from oviposition.
There are four named varieties and several other color variations, and some individuals lack the pronotal horn.
P. minax is a smaller, pale yellow species which is found in California on oak. (Dozier 1920)
Umbonia crassicornis - FL & so. TX, on ornamental and fruit trees
Dozier H.L. (1920) Notes on the genus Platycotis
Stål. Ohio J. Sci. 20: 209-212. Full text