Lepidoptera The Green Hairstreak Butterfly – Thecla Rubi
Next to Quercus, this is the most plentiful of the genus. It frequents woods and heaths in nearly every county in England, and is also found in parts of Scotland and Ireland. It is peculiar among British butterflies as being the only one that exhibits a bright green colour. It also differs from the other Hairstreaks in two important particulars, for the hind wings, though angled at the hind margin, are not ‘tailed,’ and the characteristic hairstreak which gives the popular name to the genus is here represented only by a series of white dots across the wings, or, in some cases, by one or two dots on the hind wings only.
The chief food plants of this species are the bramble (Rubus fruticosus), the birch (Betula alba), and the broom (Cytisus scoparius).
The perfect insect flies in May and June, and the eggs are deposited during the latter month on the above plants. The caterpillars are full fed in July, and change to the chrysalis state towards the end of the summer.
The colour of the caterpillar is pale green, with a yellow stripe and several white oblique lines along the sides, also a yellowish stripe down the back.
The chrysalis is short and thick, and of a dark brown colour.