Vestal Rhodometra sacraria (1716, 70.038) is a migrant which has become more common in recent years. Present in Kent in single figures until the early 80s when numbers began to increase, although there are still wide variations in numbers each year.
For example total counts in Kent in most recent years have frequently been in the 20s but in 2013 and 2015 were 206 and 301 respectively. In these years numbers entering the country can be in the thousands and specimens can be seen as far north as Scotland.
They breed continuously throughout Southern Europe, North Africa and large parts of Asia. Early arrivals may produce a generation here in the autumn although the larval stage has never been found in Britain. There is no evidence that the species can survive the winter here. Larvae feed on know grass, dock and other low growing plants.
Experiments varying the temperature that the pupae are kept at have demonstrated that this makes a difference to the appearance of the adult. High temperatures produce a lemon yellow ground-colour and a vivid pink cross band, whilst at lower temperatures the ground-colour can be a duller straw yellow or leaden brown to deep crimson, and the cross band is brown or black.
Earliest and latest dates recorded:
|East Kent VC 15||West Kent VC 16|
|Earliest date||5 May||27 May|
|Latest date||8 Nov||29 Oct|