Eristalis arbustorum on the Greensand Way

A short wander down the Greensand way path produced more Eristalis arbustorum than pertinax, somewhat to my surprise. I have seen a few of the rather dark females at Dene Park, and today I saw both males and females, so it was interesting to try to look at the details a bit more closely.

This is a close-up of the stigma on the wing, slightly blurred out towards or even beyond the junction of the Sc vein with the wing margin, as in the key.

These two photos are perhaps a slightly better view of the tergites pattern, showing how the dark patch on tergite two doesn't widen at the rear to block off the continuity of the yellow between two and three.

This is obviously a male, generally the more brightly coloured of the two sexes in this species I think. The antennae are sufficiently dark to fit the description of the species, although they may look lighter from different angles. Note also the overall clarity of the wings - apart from the stigma of course. Eristalis pertinax does I think have a bit of a wing cloud by comparison, another characteristic allowing me to separate out arbustorum from the pertinax I commonly see around Dene Park more easily.

Another feature that you can start to see is the rather nice white woolly look to the face. The lack of the face stripe is fairly characteristic of arbustorum within the genus, although wear does sometimes remove enough wool to produce a slight face stripe.

The picture below gives some idea of the "pied" nature of the legs, ivory on the tibiae and dark on the mid and fore femora and tarsi. Its not so obvious on the hind tarsus that the limb is dark on the apical half, but it is. I do think however that you can see the swollen nature of the substantial basal section of the hind tarsus below the tibia - if I've got all the sections of the limb correct! The dark fore tarsi of arbustorum contrast with the completely yellow tarsi of pertinax.

It is interesting to note their silvery hairs all around their bodies, on the dark parts of the legs, and on the eyes.

On the other hand this is one of the darker females,  most obvious first from their silvery tergite bands, then from the woolly white faces. Again note the "pied" look of the mid and fore legs, and the blurred stigma on both sexes! The other feature I think I am seeing is the white tufts of hair along the side of the thorax, again on both sexes, but I've not seen any reference to this in the books.

The next photo shows the lighter basal half of the rear tibia and the darker apical half, leading onto the obviously swollen metatarsus.

In the next photo you can just see the long hairs on the arista of the far antenna - this is one of my rather less bad pictures. The bicolouring of the hind tibia and the swollen meta-tarsus is, I think, convinging.

This is now some pictures of a male again, the first with a rather nice view of the woolly face and the trident structure part of the way up on the front of the pharynx:

This one is a great shot of the bicoloured rear tibia and the very definitely swollen metatarsus:

This is a fairly good photo of what in bees I think are called the tegulae, the joints that move the wings. In this species of Eristalis, the tegulae are noticeably black from the top, particularly with respect to the other features of the body. From the front they look as if they have a silvery pad on their front surface, as seen in the photo two above.

Still no sign of His Majesty

I particularly enjoy trying to spot the hoverflies that are found on the sides of the paths, and particularly on the Hogweed heads through Dene Park.

Today there were at least three Cheilosia illustrata, many, many Eristalis pertinax, many Myathropa florea, one Xylota segnis, one Xanthogramma pedissequum, a few Episyrphus balteatus and a lot of Melanostoma scalare, usually flying lower down.

Butterflies were a bit scarce, but there were two Ringlets over at Ringlet Corner, a few Commas and Speckled Woods, Pararge aegeria, but that was about it. 

Dene Park with BBCS Kent - and STILL no Emperor!

The Purple Emperor was again hiding his glory from his public, even from the Kent branch of the British Butterfly Conservation Society, but there were good numbers of fresh bright Commas, some Meadow Browns, a couple of Large Skippers, quite a few White Admirals, a nice Speckled Wood, Pararge aegeria, and I also found a Ringlet at Point Wood Corner.

I did find a hoverfly that I think is new to me, Epistrophe grossulariae, and the pictures were good enough on this occasion to lead me in the right direction and be reasonably convincing. Moderately sized fly, yellow on the side of thorax, generally parallel yellow bands on tergites 3 and 4, with spots on tergite 2. These open out and sweep slightly backwards rather than being true golf club shapes. Yellow bands on tergites 3 and 4 also open out and sweep slightly backwards at the edge of the tergites. Black bases to front and mid femora, black stripe on top of head leading to dark antennae, grey stripes on top of thorax.

Other hoverflies seen today were Eristalis pertinax, Episyrphus balteatus, Volucella pellucens, Melanostoma scalare, and Sphaerophoria spp.

Whitehorse Wood with the KFC

We had quite a wet morning so concentrated mainly on the plants to be found, although a few butterflies, flies, beetles and grasshoppers were seen.

The hogweed was its normal attractive self, and was drawing in a variety of flies including these Episyrphus balteatus, three on this one head - by no means unusual.

We had a good look at some remaining chalk grassland on a steep slope, where there were some beautiful field scabious plants, Knautia arvensis

We found the Essex Skipper (Thymelicus lineola) here, with the underside of its antennal tips black, as opposed to orangey as seen in the Small Skipper (Thymelicus sylvestris. No photos of the Essex Skipper, but I did manage to snatch one photo of one of the Marbled White, Melanargia galathea, taken from a rather odd angle, nectaring off a Mallow plant. This is actually a member of the Browns, rather than the true Whites.

This is Blackstonia perfoliata, a nice plant common in this habitat

There were a few Melanostoma scalare or lookalikes to be seen, this on Mignonette, Reseda luteola.

Scattered on the steep slope were some pyramidal orchids, Anacamptis pyramidalis. Note the overall uniformity of pinkish colour, the three wide-spreading oblong lower lobes and the two raised ridges running down onto the lower lip.

Friday the 13th - and still no Emperor!

This was a fairly quick visit, with the hogweed flowers starting to produce insects really well now. This fly looks at first sight as if it has an incredibly long tongue, but in fact it has incredibly long legs, with the tongue behind its front left leg!

I was really pleased to correctly identify this immature male Southern Hawker, Aeshna (or perhaps Aeschna) cyanea, and have it confirmed on ispot. You can see the filmy iridescence on its wings very clearly in the first shot. Maybe it had just emerged from one of the small Dene Park ponds, or perhaps from the shady lakes of Golden Stable Wood over the road!

Here is the female Leucozona laternaria again, possibly the same one as the past week or so if it is spending most of its time on these flowers along this section of track and I am keeping a reasonable look out!

Myathropa florea, which like the Leucozona also depends on sites like rot-holes for its larval development was also present on the hogweed, with the photo of this male showing the grey thoracic bars very well:

Another hoverfly seen was the very common Melanostoma scalare, with this highly cropped photo of a female showing the reversed triangles of yellow on the abdominal tergites beneath the wings:

At the other end of the hoverfly size scale was this male Volucella pellucens, with its shiny white band across its midriff and wing shades.

This male Eristalis has the characteristic rounded dumpiness of many of the Eristalis tenax I have seen to date, confirmed by the broad black face stripe and hairy black rear femora. This was on the St Johns Wort, I should check the popularity of these flowers!

There have been a lot of these little Tortricoid moths around on the hogweed flowerheads, which turned out to be Pammene aurana. 

And finally, here is a "blue" form female Common Blue Damselfly, Enallagma cyathigerum, 

Thunder and lightning at Dene Park

The insect of the day for me was my first Cheilosia illustrata, spotted on the flowers of the hogweed (the larval foodplant) along the track on the way in to Dene Park.


This is a furry bumble bee mimic with a wing cloud on the outer part of the wing. There is a whitish band on the front half of abdomen, followed by a black band and then a reddish tail. The inner cross vein R-M meets the discal cell before its middle. There was no loop in the R4/5 wing vein. In side view there was a clear knob on the light dusted face (you can believe the face is black beneath).

There were a lot of Eristalis around, mainly Eristalis tenax I think. It was interesting to see the golden hairs around the abdomen

You can also see this golden fuzz from the front and there are also the long golden bristles around the rear of the scutellum, and the apparent reddish-gold on the legs visible from some angles in close-up, as opposed to the overall completely blackish colour normally seen by the naked eye.

In the excellent piece of grassland by the car park, there was a nice female Meliscaeva cinctella (I think) on the hawkbit, and I've now seen a couple of these in the past few days. Note the lack of a black stripe down to the antennae on the frons, and its small size.

Evening on the Access Trail

I was late out out, today, after five, but pleasantly surprised to still find some bees and flies on the brambles and hogweed along the trail, despite the dull evening conditions.

There were hive bees, common carder bees, white/buff tailed bumblebees, greenbottles, Episyrphus balteatus, Sphaerophoria scripta, Melanostoma scalare, and some Syrphus hoverflies.

The Syrphus all looked initially to be Syrphus vitripennis, with the hind femora at least two thirds dark, as opposed to ribesii, in which they are more yellow Syrphus ribesii as the hind femora in this first one I looked at are yellow for at least the apical third or 33% (the yellow length measured in this picture as 44% on the ruler) To be Syrphus vitripennis the yellow should be less than 25%. However it does seem as though Syrphus are definitely not separatable into species and it is better just to leave this as Syrphus spp. They do all seem to be males however!

This Syrphus on the white flower looks more like Syrphus vitripennis however, with 33% or less visible as yellow, although I couldn't see the whole of the femur to be sure.

The last Syrphus, by the sloe clump near the end of MT 133, was again more like Syrphus ribesii with the yellow looking like 41% of the femur.

I saw a couple of male Sphaerophoria scripta, recognized by the wings being shorter than the abdomen, but only pictured one.

There was also this apparently silver-spotted version of Meliscaeva auricollis, only starting to colour up on the fifth tergite.

This is Melanostoma scalare, with its unique abdominal pattern quite nicely visible through the wings, easier I think when taken towards the light, or in poor light, rather than struggling with reflection off the wings.

I nearly mistook this for an Episyrphus from a distance, but it is in fact Meliscaeva cinctella,again quite a common hoverfly.

There were quite a few Common Carder bees, Bombus pascuorum around, and I did get a few pictures.

There was also an Oedemera beetle, possibly a female Oedemera nobilis without the swollen thighs of the male. The elytra in this genus are rarely if ever properly "closed":