Is it a moth, is it a butterfly? Part 1 – The Skippers

As is routinely seen across the web, the Hesperiidae (the Skipper butterfly family) suffers from misidentification as moths. So when you’re out and about, and think that’s a day flying moth, stop and double-check, it could be a charming skipper butterfly!

Over the course of this blog I will let you engage with the skippers’ lives and aid your identification skills along the way.

There are three species which you are likely to find commonly on Reading University’s Whiteknights campus they are:

Essex Skipper (Thymelicus lineola)

Small Skipper (Thymelicus sylvestris)

Large Skipper (Ochlodes faunus)

Each having their specific niches and identifiable features.

The Essex Skipper is a charming golden butterfly of the countryside, with the wings bordered by a black then white margin see image 1. With a wingspan up to 28mm. The species inhabits rough grassland, woodland rides to conservation grassland (Calcareous grassland etc), with Reading very much central to its range in the UK, but being found as far north as Hull. Interestingly, Butterfly Conservation notes that the distribution has “more than doubled in the last few decades” no doubt aided by climate change and as UK Butterflies notes, it maybe increasing its distribution, as a result of the network of grassy corridors that the motorway and major trunk roads provide.

There is just one generation per year and you are likely to see this species in July and into August. The caterpillar of the species feeds on a number of grasses but is mainly on Cocksfoot (Dactylis glomerata) see image 2, Couch Grass (Elytrigia repens) and Creeping Soft Grass (Holcus mollis). The species lays its eggs inside the furled leaf sheath of the dead Cocksfoot stem, when a suitable opening is found, where it then inserts several eggs. The caterpillar then develops in the egg, but then stays dormant over the winter hatching in the spring and immediately moves to feed on the fresh growth. The caterpillar feeds by emerging from a tube, formed by attaching a leaf blade edges together with silk. The caterpillar has 5 instars in all, with 4 moults before pupation.

Identification is possible for males and females, but key to identifying the species from the superficially similar Small Skipper is the antennae. The antennae-tip underside on an Essex Skipper is always black see image 3, as if dipped in black paint, whereas a Small Skipper’s antennae-tip below is always light brown to a dull orange. Between males and females the distinctive feature is the sex brand (small black line on the forewing) see image 4 only present in males.

Fact: It was the last British resident butterfly species to be described.  It was formally named in 1889

Such sites you may wish to visit are:

http://www.butterfly-conservation.org/

http://www.ukbutterflies.co.uk/index.php

http://www.hantsmoths.org.uk/index.htm

http://www.searchnbn.net/

Please record any sighting on campus, with dates, in the comments section below for assessment by subsequent authors.

We thank photographers from UK Butterflies for permission to use their images.  Individual credits are given with each image.