Wednesday, 7 June 2017

Hummingbird HM and 5-spot Burnets

My first HHM of the year today, resting then investigating/laying.
Also, the 5-spot Burnet caterpillars which I saw along the pavements on our road in May have turned into moths (some having pupated in cocoons attached to a lamp post).
Edit: I may have made a wrong assumption that the caterpillars, cocoons and moths are all the same species.  The caterpillars had short hairs so were either 5-spot or 6-spot and I'm not sure which species the cocoons are -  is there a way to tell?

Hummingbird Hawk-moth
Five-spot Burnets
Close-up of cocoon on lamp post
Lamp post with cocoons

3 comments:

  1. Of the two subspecies of Z. trifolii, Five-spot Burnet, decreta flies late June to early August, and palustrella flies from mid-May to mid-June. This means that your adults are form palustrella, but the documented distribution for this form does not include Ceredigion. Further investigation required.
    Based on the date, the cocoons could be Z. filipendulae, Six-spot Burnet, Z trifolii form decreta, or Z. lonicerae, Narrow-bordered Five-spot Burnet. The cocoon of Six-spot is spun exposed on the stems of grass and other herbage and occasionally on twigs of bushes, wire fences, rocks and stones. Could a lamp post be seen as a rock? The cocoon varies from bright yellow to dirty white. The cocoon of Five-spot form decreta is spun high on the stems of soft-rush or other marshland vegetation and not concealed. It varies in colour from bright yellow to cream-white or dirty white. The cocoon of Narrow-bordered is spun exposed on the stems of grass and other herbage and is translucent varying in colour from pale whitish yellow or greenish yellow to white.
    All above facts taken from "The Moths and Butterflies of GB and Ireland".
    I think the lamp post suggests your cocoons are Six-spot.

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  2. Thanks for the info, Tony.
    Is it possible that the flight season for ssp. decreta is out-of-date and therefore misleading? I think I have seen posts on other blogs in previous years that indicate an earlier fs for that subspecies (although I haven't got access to the actual records). I thought palustrella was only on chalk or limestone.
    Re: the cocoons. I had my first (of the year) 6-spot Burnet moth in the garden today.

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    Replies
    1. It is probable, as some other species are flying earlier these days, but the recent, third edition of Waring and Townsend has the flight season for decreta as July to early August. Of the 257 county records for Five-spot Burnet, only 3 are earlier than middle of June: 1st, 11th, and 12th. This may indicate that we have ssp. decreta here and not palustrella.

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