Monday, 19 July 2010

Northern Eggar, Mompha raschkiella and Beetles

The first of my Barden Moor, Northern Eggar caterpillars has produced this male imago. I photographed it this morning and it presumably took advantage of the afternoon sunshine to zoom off back towards the moorland.

My remaining caterpillar has yet to pupate.

The second photograph shows a mine in the leaf of Rosebay Willowherb which I think was made by the larva of Mompha raschkiella.

The final picture shows five beetle larvae devouring a leaf of Rosebay Willowherb (Epilobium angustifolium).

It will be a challenge to work out which species of beetle this is!


  1. Derek, you've got my well confused now!! I thought Northern Eggar pupae had to overwinter once before the adults emerge. I'm assuming your adult is from larvae found this year?

    The reason I ask is because I have a pupa reared from an early instar larva found last October.

  2. Hi Charlie,
    I confess that I am a bit confused as well! Why won't caterpillar number 2 pupate?
    From UKMoths:
    "The normal flight period in lowland southern Britain is July to August, and in the north from late May to early July. Adults from northern moors, and some dunes and southern heaths, are often larger and darker than most southern forms.

    In the north of Britain, development takes two years, in the south one year, with a zone in the Midlands and Welsh borders where it varies, probably with variation in the climate from year to year.
    Formerly, northern populations with a two-year cycle were given sub-specific status as the Northern eggar (Lasiocampa quercus callunae), but the situation is not as clear-cut as previously thought.

    When the two-year cycle is followed, larvae usually live from July to the September of the following year, and pupae overwinter from September to May.
    One-year cycle larvae usually live from September to May, with pupae in June. Rearing larvae indoors can accelerate development."

  3. My pupa is around 25 days old at the moment so I'd better keep an eye on it for the next 2 or 3 weeks just in case it pops out this year. I've moved it in to a bigger pot just in case!