Lulworth skipper their greatest since its discovery there. With a wingspan of 24 to 28 millimetres, females being larger than males, the Lulworth skipper is a small butterfly, the smallest member of the genus "Thymelicus" in Europe and among the smallest butterflies in Britain. Aside from the size difference, the sexes are distinguished by females having a distinct circle of golden marks on each forewing. Due to their likeness to the rays around the eye of a peacock's feather, these are often known as "sun-ray" markings, and they can faintly appear on males. The Lulworth skipper was first described by German entomologist
Lulworth Castle nearby. In the 1970s, restoration work began with the help of English Heritage. The restoration, finished in 1998, included a new roof and restored surviving walls in the interior, but no new internal walls or replacements for the destroyed upper floors were constructed. The castle is still owned by the Weld family and is a tourist attraction, holding medieval-themed events. Part of the Lulworth Estate is in use as an MoD firing range as well as a wildlife conservation area. Since 2017, the site has been used as the location for the Bestival music festival, with the castle's foreground being