A slow walk down the access trail revealed two species of click beetles, the wasp beetle Clytus arietus and several good views of solitary wasps and hoverflies. Here is the first of the click beetles a deep black one. I did wonder whether it might be Hemicrepidius hirtus, a fairly common all black species (including its legs, important in ID) with obvious ridges down the elytra, as seen in these pictures I think.
the pectinate, or if you prefer, serrate, antennae:
and this is the second insect, demonstrating the more usual colour of click beetles, possibly an Athous species such as haemorrhoidalis or an Agriotes species such as lineatus. The larvae of species such as these are common agricultural pests known as wireworms!
These pictures show the angular processes at the posterior margin of the pronotum very clearly!
The next insect is one I have heard of, and seen photos of, before. it is the highly distinctive, and indeed unique, wasp beetle, Clytus arietis, of the family Cerambycidae or long-horn beetles:
There is nothing else like this in the Coleoptera, and whenever I have seen a picture of it, I have wanted to see it in real life. Why it would wish to imitate a wasp, when it is already such a tough cookie, is difficult to imagine. It really does appear to be genuine mimic, because it even makes jerky wasp-like movements on flowers, and a waspish buzz when threatened, presumably to try to convince attackers that it is a genuine wasp! This one seems to have its legs all over the place, and hasn't tucked its pair of flying wings properly under the elytra either.
The elytra are rounded as seen here, and the colour pattern is as seen here. The yellow bands on the square pronotum are typical, with the posterior one divided, as it quite commonly is.The legs are orangeish although the femora are darker. All tibiae have an apical inner spine. Overall the beetle is about 9 - 13 mm long.
The adults are often found visiting flowers and are harmless. The larvae tend to live in dead wood, at first just under the bark, and later in the xylem. The wood used includes dead parts of living trees, dead trees or even fallen dry branches. There is plenty of all of these categories of dead wood along the Access Trail, so the larvae would have had plenty of choice for their homes!
The femora may actually appear quite short and broad, and specifically clavate, particularly in contrast to the apparently much longer thinner tibiae, as demonstrated in this unusual view taken from the rear of the beetle crawling from one leaf to another (unless this is just fore-shortening - it is!):
In the slightly serrate antennae the third segment is clearly longer than the fourth, an identification point worth noting. The first four segments are notably orange in contrast to the darker more apical segments
There were quite a few other insects around, including a few hoverflies. Here is the very common marmalade fly, Episyrphus balteatus, I think a male, very battered, poor thing!
Here is another one, moderately small, but I have no idea of what species it might be. I took a wild guess at Cheilosia but it could well be a whole load of other things as well!
The next hoverfly is another very common one, a male Sphaerophoria scripta, a tiny and very characteristic species.
This is a much bigger hoverfly, but also a very common one, Eristalis tenax, the Drone Fly, with its wide dark facial stripe, and very black rear legs. This particular individual is very dark on the top of the abdomen, usually there are some clear orange sectors here:
Rather nice to see was an immature Common Blue Damselfly, Enallagma cyathigerum, settling quietly from its exploration of the bottom of the hedgerow, with the beautiful lilac colours of a newly emerged adult. The broad blue sub-humeral stripes, the lack of a "Coenagrion spur" on the sides of the thorax, and the dark mushroom on section 2 of the abdomen are indicative of the male of this species, separating it from other blue species such as the Azure Damselfly.
By now I was thinking I was doing really quite well for insects, and a solitary female bee a little further along proved me right when it looked a lot like Andrena chrysosceles. I thought I saw this species at least once before, on the Shepherds Needle down towards the Gravel Pits, but no-one replied to my posting of that insect on ispot for checking. Lets see if the ispot people can help me out this time! This bee was sitting on an ash leaflet on the edge of the Green Lane shaw, grooming itself gently. Because it was fairly still, it allowed a series of photographs, all in the same posture.
The reason I think it is chrysosceles is as follows. It is a smallish Andrena bee, with the typical shape and hairiness for the genus. It is also female because of the long brush of hairs (scopa) on the rear legs. The thorax is lightly coloured with tawny but not fulvous hairs. The abdomen is a relatively shiny glossy black and has very clear close knit bands of silvery hairs running across it (I have seen one picture on the BWARS website that might indicate these bands can be worn away a bit on the top surface, but this may also depend on the light). There appears to be a reddish tuft of hairs at the end of the abdomen. The legs are dark at the base, the femora, but bright gold-orange further down, at the tibiae, and this extends right to the end of the foot, the tarsi and metatarsi.
The male of the species is similar but has white hairs in a moustache on the face, with a white clypeus with two small black dots either side.
There was another female Andrena bee almost immediately, but very clearly of a different species. Actually I now think this is Andrena nitida (2021). This one was much more robust, again with a glossy black abdomen, but larger and more rounded, without the obvious white bands across the abdomen, or the thin white side tufts on the first segments of the abdomen.
the pectinate, or if you prefer, serrate, antennae:
and this is the second insect, demonstrating the more usual colour of click beetles, possibly an Athous species such as haemorrhoidalis or an Agriotes species such as lineatus. The larvae of species such as these are common agricultural pests known as wireworms!
These pictures show the angular processes at the posterior margin of the pronotum very clearly!
The next insect is one I have heard of, and seen photos of, before. it is the highly distinctive, and indeed unique, wasp beetle, Clytus arietis, of the family Cerambycidae or long-horn beetles:
There is nothing else like this in the Coleoptera, and whenever I have seen a picture of it, I have wanted to see it in real life. Why it would wish to imitate a wasp, when it is already such a tough cookie, is difficult to imagine. It really does appear to be genuine mimic, because it even makes jerky wasp-like movements on flowers, and a waspish buzz when threatened, presumably to try to convince attackers that it is a genuine wasp! This one seems to have its legs all over the place, and hasn't tucked its pair of flying wings properly under the elytra either.
The elytra are rounded as seen here, and the colour pattern is as seen here. The yellow bands on the square pronotum are typical, with the posterior one divided, as it quite commonly is.The legs are orangeish although the femora are darker. All tibiae have an apical inner spine. Overall the beetle is about 9 - 13 mm long.
The adults are often found visiting flowers and are harmless. The larvae tend to live in dead wood, at first just under the bark, and later in the xylem. The wood used includes dead parts of living trees, dead trees or even fallen dry branches. There is plenty of all of these categories of dead wood along the Access Trail, so the larvae would have had plenty of choice for their homes!
The femora may actually appear quite short and broad, and specifically clavate, particularly in contrast to the apparently much longer thinner tibiae, as demonstrated in this unusual view taken from the rear of the beetle crawling from one leaf to another (unless this is just fore-shortening - it is!):
In the slightly serrate antennae the third segment is clearly longer than the fourth, an identification point worth noting. The first four segments are notably orange in contrast to the darker more apical segments
There were quite a few other insects around, including a few hoverflies. Here is the very common marmalade fly, Episyrphus balteatus, I think a male, very battered, poor thing!
Here is another one, moderately small, but I have no idea of what species it might be. I took a wild guess at Cheilosia but it could well be a whole load of other things as well!
The next hoverfly is another very common one, a male Sphaerophoria scripta, a tiny and very characteristic species.
This is a much bigger hoverfly, but also a very common one, Eristalis tenax, the Drone Fly, with its wide dark facial stripe, and very black rear legs. This particular individual is very dark on the top of the abdomen, usually there are some clear orange sectors here:
Rather nice to see was an immature Common Blue Damselfly, Enallagma cyathigerum, settling quietly from its exploration of the bottom of the hedgerow, with the beautiful lilac colours of a newly emerged adult. The broad blue sub-humeral stripes, the lack of a "Coenagrion spur" on the sides of the thorax, and the dark mushroom on section 2 of the abdomen are indicative of the male of this species, separating it from other blue species such as the Azure Damselfly.
By now I was thinking I was doing really quite well for insects, and a solitary female bee a little further along proved me right when it looked a lot like Andrena chrysosceles. I thought I saw this species at least once before, on the Shepherds Needle down towards the Gravel Pits, but no-one replied to my posting of that insect on ispot for checking. Lets see if the ispot people can help me out this time! This bee was sitting on an ash leaflet on the edge of the Green Lane shaw, grooming itself gently. Because it was fairly still, it allowed a series of photographs, all in the same posture.
The reason I think it is chrysosceles is as follows. It is a smallish Andrena bee, with the typical shape and hairiness for the genus. It is also female because of the long brush of hairs (scopa) on the rear legs. The thorax is lightly coloured with tawny but not fulvous hairs. The abdomen is a relatively shiny glossy black and has very clear close knit bands of silvery hairs running across it (I have seen one picture on the BWARS website that might indicate these bands can be worn away a bit on the top surface, but this may also depend on the light). There appears to be a reddish tuft of hairs at the end of the abdomen. The legs are dark at the base, the femora, but bright gold-orange further down, at the tibiae, and this extends right to the end of the foot, the tarsi and metatarsi.
The male of the species is similar but has white hairs in a moustache on the face, with a white clypeus with two small black dots either side.
There was another female Andrena bee almost immediately, but very clearly of a different species. Actually I now think this is Andrena nitida (2021). This one was much more robust, again with a glossy black abdomen, but larger and more rounded, without the obvious white bands across the abdomen, or the thin white side tufts on the first segments of the abdomen.
Note the blackish hairs at the rear of the abdomen, though probably not a reliable character.
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