Spiny oak slug
The spiny oak slug is the larval form of a moth in the family Limacodidae.
Life cycle
There is one generation a year in most of the northern parts of its range, with caterpillars seen from late June to October. Two generations or more from Missouri south.Egg
are laid singly or in small clusters on leaves.Larva
Euclea delphinii is the only species of its genus to exist in West Virginia. Euclea caterpillar larvae are variable in colour, with the most common colouration being yellowish green, with bright red, square subdorsal markings- making this a distinct ID feature for this species. Orange hues are also common, alongside the red square subdorsal markings.The larva is flattened and ovoid in outline, with spiny tubercules along the back and sides. These are venomous, producing symptoms in humans that vary from mild itching and burning to more serious reactions that require medical attention. The sides have craters ringed with black or white along them. This species has 8 instars in total, with the first instar being a small, whitish larva with subdorsal tubercules. In the final instar they usually have two to four sets of black hairs at the tail end, that can fall off, called 'caltrop' spines after the Roman defensive weapons. Colourful, but the colours vary enormously. with orange, green, lichen and orange-green Florida forms also recorded, although less common. Like all limacodids, the legs are shortened and the prolegs are reduced to suction cups. Maximum length, 20 mm.Pupa
Pupates in a cup-shaped cocoon with a circular escape hatch.Adult
The small moth is 'hairy' and brown, with green patches on the upper wing. The underwing is a paler grey-brown.Parasitoids
A number of parasitoids have been recorded on spiny oak slug caterpillars, including tachinid flies, eulophid wasps, and braconid wasps. An egg parasitoid of genus Trichogramma was also recorded.Phenology of Caterpillar
The caterpillar distribution varies, most notably from June to October. With the adults appearing in April to September. Overall, this species' range is from East Minnesota to Maine and New Brunswick all the way to where it's most commonly found, in West Virginia. Male populations also outnumber female populations drastically.There is one generation of caterpillars per year in most of the Eastern U.S., mostly being active from late June to October. 2 generations of caterpillars occur in Missouri and the Deep South, where there are more presumed to be in this area.