Essex Skippers (Thymelicus lineola) in Derbyshire

July 30:2011:
Over recent years Essex Skippers have gradually spread northwards through England and are now well established in Derbyshire. A visit today to a locality near Willington provided an opportunity to compare the Essex Skipper with the very similar Small Skipper. This was at a large rough grassy field, ideal skipper habitat, with flowering thistles, ragwort, willowherb, clovers and much else. Essex Skippers emerge slightly later in the season than Small Skippers and here they outnumbered the latter by a ratio of at least 3 to 1.


[Skipper field at Willington]

The two species are very similar both in appearance and in habit and are difficult to separate unless a very close view can be gained. The easiest distinguishing character is that the Essex is black on the underside of the antenna clubs, whereas in the Small this is brown-orange. Another difference is that the male Essex has a short line of dark scent scales on the upperside of the forewing which runs parallel to the wing's edge. In the Small Skipper this line is longer and curves slightly away from the wing's edge towards the abdomen. Photos showing these main distinguishing characters along with more general ones of the Essex Skippers are below.


[Essex Skipper showing black on the underside of the antenna clubs]


[Essex Skipper (male) showing the short dark scent scale line running parallel to the forewing edge]


[Small Skipper showing orange-brown on the underside of the antenna clubs]


[Small Skipper (male) showing the longer dark curved scent scale line slightly diverging from the forewing edge]

A few more Essex Skippers photos are below.

BUTTERFLY: Silver-spotted Skippers (Hesperia comma) at Aston Rowant, Oxfordshire

August 11, 2010:
Following a lack of improvement to the dismal summer weather locally, the forecast for some decent conditions in southern England prompted a day-trip to the Chiltern area to see the Silver-spotted Skipper (Hesperia comma).

This is a relatively rare butterfly in Britain and is at its north-western European limit in southern England. Aston Rowant, close to where the M40 motorway cuts a deep groove through the chalk hill-side, is one of its strongholds and is the most northerly British colony of any size.





This is a late-emerging, single brooded butterfly not on the wing until late July but which then continues to fly throughout August. It is restricted to warm, south-facing slopes on chalk downland where the turf is kept short by grazing and its larval food-plant, Sheep’s Fescue, grows. At Aston Rowant, on the steep warm hillside, there were many small bare patches of chalk presumably exposed by rabbits and it was on these warm areas that the butterfly sometimes basked. However, once the sun went in they would cease to fly but would immediately resume on its return.



[Basking over warm patches of chalk exposed by rabbits]

The butterfies flew fast and low and being of a dull greenish-ochre colour below were hard to follow. However, once settled the prominent silver spots, especially noticeable on the underside of the hind wing, could be seen. The females were darker in colour than the males, the latter having a line of dark scent scales on the forewing similar to some other skippers such as the Large Skipper. A wide range of nectar plants were apparently used but thistles and composites were probably the most favoured. There must be a very large population here as they were regularly encountered over most areas of suitable downland.


[A heavily marked female, above]



Although the most frequent skipper was the Silver-spotted, a few Essex Skippers (Thymelicus lineola) were also seen. These are much more widespread in Britain and nothing like as scarce. The Essex can be distinguished from the very similar Small Skipper by having black tips to the underside of their antennae (rather than brown as in the Small). Also, they have a shorter line of dark scent scales running parallel to the outer edge of the fore-wing, not longer and angled away as in the Small.



[Essex Skippers, showing the black underside to the antennae and characteristic line of scent scales]