Saturday 29 July 2017

when is a tick not a tick?

A short walk out this morning, didn't produce and large mammal sightings but a number of smaller critters took my attention.  The first was an Orange Ladybird - I've only see one of these prior to this year, but I've seen several so far this year - followed by a Red-legged Shieldbug/Forest Bug.



My first new species was the small Soldier Fly, Black-horned Gem Microchrysa polita sitting on a Sycamore leaf. This was followed by finding the egg sack, and attendant female spider, Paidiscura pallens, a species Mark put me onto a couple of years ago, under another Sycamore leaf. 

  Black-horned Gem

  The "sputnik" shaped egg sack and attendant mum of Paidiscura pallens

The same leaf also sheltered several Common Sycamore Aphids, Drepanosiphum platanoidis including two that appeared to be sat over some form of spangle gall. A bit of investigating has discovered that the "gall" is, in fact, the cocoon of the parasitoid wasp Dyscritulus planiceps. A check on NBN Atlas shows only 6 records for this species across the UK, and none in Wales! Is it that rare, or just overlooked? It might be worth looking under the leaves of Sycamores to see if you can find any aphids apparently sitting over a 2-3mm wide disk.

                                 Mummified Sycamore Aphid and Dyscritulus planiceps cocoon

As I didn't see the wasp itself, so whilst the species is recorded, can I tick it?

4 comments:

  1. An interesting little haul there. I'll keep my eyes pealed for those wasps.

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  2. Re: orange ladybird, I've also bumped into them more this year, plus larvae, always in hedge sycamore, which appears to be holding plenty of tar spot.

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  3. They are a mildew muncher, so perhaps they find something in Tar Spot too. I've seen more Harlequins than ever this year; including in my garden for the first time.

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  4. I've just found one of those wasp cocoons.

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