Monday, 1 August 2011

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.

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