Saturday, June 24, 2017

There's a hole in my pupa, dear Liza...

I want to begin this update with an example of how a chance encounter, and further investigation, led me once again to discover more about nature than I would ever have known otherwise.

On a recent visit to my local hospital, I noticed as I walked back to the car park, an area of grass that had been allowed to do its thing and go to seed. On the long stems I spotted burnet moth pupae. One in particular caught my eye because it seemed to be a double: one directly on top of another. I decided to take it home to observe. I'd had it a couple of days when I did my usual morning check, to find a hole in each of them. Not where a moth had emerged, it was too small for that...




It looked like the work of a parasitic wasp; but I had no knowledge of wasps that attack burnet moth pupae, and so a little detective work was called for. 
Ironically, as I was settling in to that research, I was distracted by what sounded like something tiny hitting against my studio lighting. Ha! Two teeny wasps were buzzing around, and occasionally, hitting against, the strip lights. I managed to capture them both to photograph before releasing; they would also help confirm an identity...

Brachymeria tibialis - A Chalcid Wasp

And what a hind femur and tibia this little wasp has huh? Now this is what I just love about having an interest in nature and discovering facts purely through being mindful enough to look past the obvious. This rarely seen, 5mm wasp turned out to be quite a special creature. Its habitat is grassland where moths of the Burnet family (Zygaena sp.) are found. Although, as with many invertebrates, it is probably vastly under-recorded, it was only added to the British list in 2008 and there were only three British records by 2009. Status: Nationally rare.






You have to wonder what the necessity for those rugby-player thighs is all about? 





Another recent, exciting find was these shieldbug nymphs...


Definitely the youngest nymphs I have seen of the hawthorn shieldbug Acanthosoma haemorrhoidale. Spurred on by my fellow 'Flickrite' Maria, who is queen of the shieldbugs and on a quest to find ova, I returned to the dogwood tree where I found these, to see if I could spot any eggs. What followed was one of those, oh so frustrating times that seem to blight my world way too often. 

Imagine my delight when after searching and searching, I finally found a clutch of eggs! I was overjoyed (temporarily anyway) even though I couldn't prove they were actually hawthorn shieldbug eggs. They were on the very same tree, so it was looking good. Delight soon turned to despondency though, when the adrenaline rush faded and my logical(ish) brain began to function once more: Hmmm...those eggs look a tad grey to me. When was the last time I saw some that looked similar? I know, when I found a batch a few years ago that had been attacked by a parasitic wasp...



Here they are anyway...








And here's what emerged a day later...







From bugs to beetles: you will have to cut me some slack regards quality of this video but watching this ground beetle amble along, I was struck by how it moved all six legs. What I should have done is recorded in slow-motion, instead this is just the original slowed down, which results in the rubbish quality. But it does demonstrate nicely what happens...



It seems to follow this pattern: Front and hind right, plus middle left, followed by front and hind left, plus middle right. Meaning that they are almost moving their legs in pairs; well , two lots of three, if that makes sense? I was about to say, let's move away and have a look at what I have found in the garden recently; but that beetle was in the garden, which, even though I say so myself, is looking fabulous (in parts at least) now...





 How about the discovery of a thick-headed fly...


This could well be Sicus ferrugineus, a Conopid, or Thick-headed fly. Strange? 'Ugly' seems to be the word most often associated with these flies. Their larvae are quite 'dark' characters too: they are endoparasites of bumble bees and they pupate and overwinter inside their victims. Endoparasite refers to those that live inside their hosts; whilst the parasites that choose to live on the outside of their hosts are called Ectoparasites.


This tortoise beetle was something of a photographic experiment. Wanting to use natural light, but retain as much depth of filed as possible, I went for a setting of f20 with an exposure of 0.8 seconds (yawn!)...











C'mon...if cuteness were a crime, this one would be in big trouble!

This little beauty is Cionus alauda - a bird-dropping mimic weevil. Associated with figwort and described as a 'local species', well it was certainly local to me, it was in the garden. The next one I am unable to provide a positive ID for based on the photograph. Probably an acorn weevil? 






The beautiful structures in the picture below, are a form of protection from parasites for the larvae of a weevil that I am pretty confident is Hypera rumicis. Maybe those shieldbugs would benefit from something similar?






Enough with the weevils; I will put an end to this update with a happier story. How about the smiling faces of a batch of common green shieldbugs that were healthy...


These avoided the dreaded parasitic wasp invasion and emerged as nature intended (although, I guess you might say that having wasps emerge instead is also as nature intended).



And they soon changed to a less teneral colour...


It's a strange irony that green shieldbugs begin life as green, then change to brown, before becoming green again, only to change back to brown come the autumn. Whilst you ponder that thought, I will away to the woods and meadows of the Garden of England to see what else I can discover...



2 comments:

Rockwolf said...

Well I'm glad I've finally got around to catching up as would not have wanted to miss this one!!
That Burnet parasitising wasp is just fantastic! Wow! Spectacular shots of it too.

Just love those Hawthorn SB nymphs. And I get a mention! A very belated thank you! :-)
Those eggs that you found, are Pentatomidae... wrong shape for Acanthosomatidae which tend to be more oval... shame they were parasitised as well though.

Love all the weevils! Such beautifully detailed images again; especially the dewy pupal cases!
And so lovely to finish on a successful clutch of shieldbug eggs! I adore those hatchlings!

Mx

JJ said...

Yeah...that was a real treat for me to learn about too Maria. Yes, couldn't resist name-checking you regards the nymphs: after all, you have become something of an expert on all things shieldbug ;-) Yes, OF COURSE! How stupid of me...Hawthorn SB eggs would be more like the Parent bug ones I recently photo'd (will add those to next update too by the way). At least I don't feel SO bad now about missing out on the ones I really hoped they were.

Weevils are fab! Thanks once again for taking time out to write these comments. In a world where the 'like' rules, you are an exception that has to be cherished.