Showing posts with label Episyrphus balteatus. Show all posts
Showing posts with label Episyrphus balteatus. Show all posts

Friday, 2 October 2015

Sun!

Our summer has been one long stream of anticyclones coming in over the Atlantic, bringing high winds and rain for almost four months. As a result, flying insects have been far less frequent than usual, with hedgerows and verges almost deserted for much of the year. Flowering plants don't seem to suffer quite as much, but perhaps the number of blossoms is down.

Late September and early October have seen the arrival of a high-pressure system that has 'stuck' in place over the UK and Ireland, bringing dry days and colder nights. The circulating wind has brought warm southerly air to Ireland, leading to an influx of European species to supplement the meagre numbers of locals. At one point last week I had 7 specimens of Silver Y moth in my greenhouse.

By a strange coincidence, this is the time of year for the second generation some of our native butterflies to emerge and prepare for hibernation. A large Sunflower which I grew this year has been very attractive to Small Tortoiseshell and Peacock butterflies:

Small Tortoiseshell

Peacock
These will hibernate until March or April next year, when they will emerge to lay eggs, and the first 2016 generation will start. Both of these species use Nettles as their sole foodplant.

This is the first year for my new greenhouse and I tried different plants to see how they got on. I noticed after a while that pollination was largely being performed by a single male Episyrphus balteatus hoverfly:

Male Episyrphus balteatus
He was seen most days for perhaps 3 weeks, and made no attempt to escape through open vents or doors. Seems he was content to have a monopoly of the tomatoes, cucumbers, peppers and melons.

Thursday, 11 September 2014

Sun!

This week has been a bit of a surprise: mist in the early morning followed by absolutely clear blue skies all day. Quite delightful, really.

I have been examining my local Hawthorns for miners and came up with this rather interesting specimen:

Stigmella perpygmaeella mine on Hawthorn

It's the mine of the micromoth Stigmella perpygmaeella, which is new to my species list. At point A (the head of the mine) we can see the miner (yellow larva with oval head). But at point B we can see another, different, larva. This second larva has the look of a hymenopteran about it (round shoulders, tapering body) so it will be either a sawfly larva or a wasp larva of some sort. It is clearly heading towards the miner, so it looks like we have a predatory larva in the mine. I knew that miners could be parasitised by Braconid or Chalcid wasps, but this is an entirely new relationship. More research....

While I was working the Hawthorn, I found a few nymphs of the Hawthorn Shieldbug:

Final instar nymph of Hawthorn Shieldbug
This is the fifth and final stage of the nymph: at the next metamorphosis it will be the adult.

Capitalising on the good light, I went up to the local heath to see what I could find. Devils-bit Scabious is one of the latest plants to flower, and the path was lined in purple.

First to catch my eye was this pale pink variant:

Pink Devils-bit Scabious
I have seen this sport before, but it seemed there more around than usual this year. It looks like the pale colour doesn't put off the pollinators.

This shot shows another oddity which I see from time to time:

Viviparous flower of Devils-bit Scabious
The bud at the top is a viviparous flower growing out of the flower below it. It isn't a branch, because the stem arises from inside the lower flower. Not quite sure why this happens.

Here's a shot of the hoverfly Episyrphus balteatus on a normal flower:

Episyrphus balteatus on Devils-bit Scabious
I noticed this cluster of Russulas from the path side and immediately thought "Russula mairei", which is common everywhere around here, but then I realised there were no Beeches around:

Russula emetica - The Sickener
The trees above are Fir and Pine and the mushrooms are growing through Sphagnum. This is classic habitat for Russula emetica, which I have been hunting for perhaps 10 years. This habitat is perfect for it, so I wonder why it has taken so long to get here. New to my species list, at last.

Russula emetica - The Sickener
Russula mairei is known as the Beechwood Sickener, but Russula emetica is known as The Sickener, as you might guess from its specific name.

Monday, 11 July 2011

1400 species milestone

The weather has been very wet with some torrential downpours, but there have been a few opportunities for quick forays in the bad light.

During the long periods spent indoors, I got on with a bit more watercolour painting and updated my Species Index. I was delighted to click my tally over the 1400 mark.


Just to put the 1400 species into context, the vast majority of the photographs are taken within a 2-3 kilometre radius of my house. I have made a few forays further afield to ancient woodland, beach and limestone habitats, but the 1400 species should be regarded as our 'local' wildlife. If I spent more time travelling to e.g. coastal areas, then the species list would be much higher. 


I'll start with a few moths:
Coxcomb Prominent Moth
The Coxcomb Prominent - Ptilodon capucina - feeds on a wide range of deciduous trees, and would be much better camouflaged if it was found on a branch or on leaves.

The Riband Wave has two main colour forms, but all my specimens have been f. remutata, which are missing the grey central band on the wings:
Riband Wave f. remutata
The Riband Wave feeds on many low-level herbaceous plants.

The White Ermine is a very common moth at this time of year. I saw this male specimen and decided to get a shot of those wonderful antennae:

Male White Ermine, showing antennae
White Ermine also feeds on low-lying herbaceous plants such as Docks.

Some of our tiniest moths are also the most beautiful. This Micropterix aruncella is only about 3-4 mm long:

Micromoth Micropterix aruncella
The larval stages of Micropterix aruncella are not known from the wild, but they are thought to feed at the base of plants.

Hoverflies are now becoming more numerous, despite the bad weather.

Here are a couple of shots of Episyrphus balteatus, which is very recognisable due to the paired black stripes on the abdomen:

Episyrphus balteatus hoverfly


Episyrphus balteatus hoverfly
These shots are of two different specimens, but I note that in each case the rear left leg is the one that is used to grab the first anchoring point.

One of my favourite hoverflies is Leucozona lucorum:

The hoverfly Leucozona lucorum

It's a mid-summer species, and will soon be joined by the closely-related Leucozona glaucia, and if I'm lucky Leucozona laternaria.

Last week I showed an Ichneumonid in the process of laying eggs. This week, I managed to get a shot at the moment when the ovipositor is being released from its protective sheath:

Ichneumonid deploying ovipositor
A couple of points are worth noting here: the ovipositor is bowed towards the sheath, showing that some force is required to spring it forward. This force is released very suddenly, swinging the ovipositor very quickly towards the target. I estimate that the whole process of release to target is approximately 0.3 of a second.

Although I can't identify Ichneumonids to species (a fact that annoys me more than you will ever know), I know when I see one that is new to me, and I haven't seen this wine-coloured specimen before:


The very long antennae and lack of ovipositor suggest that this might be a male. I suppose it's worth pointing out that male Ichneumonids are quite rare, since they are an 'optional extra' in their reproductive process.

At this time of year, most of the grasses are in flower, making large swathes of colour in the hedgerows. This is Yorkshire Fog - Holcus lanatus:

Yorkshire Fog - Holcus lanatus

This, on the other hand, is the fungal infection Epichloe typhina, which actually stops the plant from flowering:  there is no flowering shoot above the fungus, just a single leaf.
Grass Choke - Epichloe typhina

Tuesday, 13 July 2010

Angelica est arrivé

The annual opening of the Angelica is a time to rejoice: the readily-available nectar is a major food resource for many insects, especially those with shorter tongues. Over the next few weeks I expect to photograph bees, wasps, ichneumonids, Ectemnius wasps, moths, beetles, sawflies and butterflies, many of them sharing the large flowerheads. This is a close-up of the social wasp Dolichovespula norwegica, which builds its nest in trees:

Dolichovespula sp. wasps appear to have a 'long face', which can be readily confirmed by the gap between the eye and the jaw.

Episyrphus balteatus is one of the more recognisable hoverflies, due to the unique 'twin-bar' marks on the abdomen:

Having recently shown the White Plume moth, it's nice to show the much more common Emmelina monodactyla plume for comparison:
(These also feed on Convolvulus sp. bindweed)

Family associations are a feature today. This is Udea lutealis, a very common relative of the Udea olivalis micromoth that I showed the other day:

I always think that ferns make an excellent background for insect photos.

Wednesday, 1 July 2009

Happy birthday, dad

Emmelina monodactyla is one of the Plume Moths. These have wings that retract like a venetian blind when the moth has landed. A system of hooks and eyes keeps the wings in shape when in flight. I haven't worked out a benefit for this complex system, other than a very narrow profile when resting.


Another Episyrphus balteatus hoverfly that initially appeared to be looking for aphids, but this one was nectaring on the recently-opened Meadowsweet.


Greater birds-foot Trefoil has opened. I used to think that I had some Greater mixed amongst the ordinary, but every specimen that I have examined locally turns out to be Greater. Ordinary Birds-foot Trefoil is earlier and, in my experience, more coastal.

Sunday, 28 June 2009

Aphids in trouble again

I noticed that the Knapweed was covered in brown aphids, so I settled down to see if any female hoverflies came along. Sure enough, a female Episyrphus balteatus arrived and as soon as she spotted the aphids she started to lay. The aphids are in trouble, since her larvae will consume them by the hundred.


Sometimes she laid her eggs quite distant from the aphids (but always on the same plant). At other times she laid a lot closer:


Spiders are the major gap in my knowledge. I must start on them next year.

I was getting acquainted with emerging specimens of Angelica, in preparation for the July flowering, and I spotted this mine of Phytomyza angelicastri:


A couple of additional images of Dactylorhiza orchids with slightly unusual markings. This one has very vague nectar guides:


And this one has nectar guides which are much redder than usual: