Wednesday, 1 July 2015


Insect heaven . . .

Copied form Calderdale-wildlife.blogspot.

These were about as we surveyed meadows and woodland for plants last week.

What is the validity of Northern Eggar as a specific name?

Eggar, Northern or Oak ? Near Mytholmroyd.
Best focus my camera could get as he shivered on  my finger.

Common Blues mating. Luddenden Dean.


AndyC said...

There are two subspecies of this moth, ssp. callunae (Palmer), the Northern Eggar and ssp. quercus (Linnaeus), the Oak Eggar. The main difference are in habitat preferences and phenology, callunae has a two year life-cycle whilst quercus completes its growth in a single year. In Derbyshire Harrison and Sterling (1986) comment that in callunae (the most frequent of the two) the adult insects are only found in odd-numbered years. In Yorkshire this seems to be the case in the west (see Kettlewell, 1973 for example), however in the North York Moors adult insects are recorded in both odd and even years, although there have been no indications of numbers involved so it may be that the majority are synchronised in odd-number years. Yorkshire records which distinguish between the two suggest that quercus is only found in the south-east of the County (Spurn Point, VC61, and possibly Hatfield Moor, VC62). Callunae is common on high moors and lowland mosses throughout vice-counties 61-64, although not recorded from VC65 there seems to be no reason why it should not be present.
In Calderdale we have also recorded the rare F olivacea dark form at Hardcastle crags.

Steve Blacksmith said...

Thanks Andy.