Guidance on telling the Brown Argus, Aricia agestes, from the female Common Blue, Polyommatus icarus, can be found on this website, http://www.glaucus.org.uk/BflyBlues03.html.
Here are a couple of heavily cropped shots of what is definitely a Brown Argus, probably a male, bacuse the spots on the forewing upper don't quite reach to the front of the wing:
My photos do seem a bit soft at the moment. I'm not sure whether this is because I'm using a small aperture, or because of the high ISO, or because of the high degree of cropping I'm having to do. So I'm going to up the lens in order to reduce the amount of cropping required. I'll also consider buying a Canon lens to see if the quality of the lens makes any difference.
I find it truly remarkable that this butterfly was once really quite restricted in its distribution and threatened in the UK. Luckily it seems to have benefited greatly from warmer temperatures and is now able to take advantage of a wider range of food plants in newer parts of the country.
I noticed two apparently male Brown Argus behaving oddly. The front one, smaller, and a lot less worm was apparently displaying mate refusal signals. He/she was quivering his/her wings and had pointed the tip of the abdomen vertically upwards in what I believe is known as the mate refusal posture, normally exhibited by mated females who "wish to be alone". The two remained in this sort of position for about a minute before the rear one flew off.
It then took about 10 seconds for the front one to stop its quivering and posturing, and then it eventually flew off as well.
Where am I going wrong? Were they both really males, as I interpreted the wing patterns, in which case why was the front one exhibiting mate refusal posture? Is that normal behaviour for males to do?
Or was the front one actually a female, with the orange spots not quite reaching to the front of the fore-wing? In which case how accurately can one really identify gender in Brown Arguses, including that of the rear one in these photos?
This butterfly, on the other hand, is a female Common Blue, from its white edgings to the orange spots on the rear wing, the whitish spots on the front of the forewing, and the lack of a clear dark mark in the centre of the forewing. Confirmation can be obtained from the spots seen fairly near the body on the underside of the forewing.
The Brown Argus is on its second brood, by a couple of weeks. It should be egg-laying and I would hope to see females fluttering about at low level looking for lush shoots of Rock Rose, Helianthemum nummularium plants to lay on.
As yesterday, there was one gorgeous Small Copper, Lycaena phlaeas, to be seen. This one was actively feeding on Marjoram, Origanum vulgare (L.), probing different flowers on one head very busily. I could not tell whether this was a male or a female, although I would have thought it might have had more rounded wings, making it a female. The subspecies found in the UK is Lycaena phlaeas eleus, first defined by Fabricius in 1798 in Germany, as opposed to the type named in Sweden. Amongst other things he described the antennae as brown, white ringed, with a black, oblong club, tip rust-coloured [although the base of the antennae actually looks white on the underside, on the basal half, as seen in the second picture]. Its really nice to see the copper hairs on the frons, and the dark chocolate brown of the eyes.
The primary larval foodplants are Common Sorrel (Rumex acetosa) particularly on calcareous soils and Sheep's Sorrel (Rumex acetosella) particularly on acid soils. Broad-leaved Dock (Rumex obtusifolius) is also used very occassionally - possibly when the sorrels are affected by drought. "Forewings dark brown with a bright reddish yellow discal region with large black spots, grey beneath with a reddish orange discal region with (small?) black eyespots. Hindwings greatly notched and generally twin-tailed, dark brown, with a bright band with short teeth, reddish yellow, grey beneath with minute black spots and a faint reddish yellow outer band" (Fabricius, 1798).
Today I must have seen hundreds of Meadow Browns, Maniola jurtina, all of which seemed to be feeding on the abundant nectar sources available. Here is a nice female on Wild Rosemary:
Here are a couple of heavily cropped shots of what is definitely a Brown Argus, probably a male, bacuse the spots on the forewing upper don't quite reach to the front of the wing:
My photos do seem a bit soft at the moment. I'm not sure whether this is because I'm using a small aperture, or because of the high ISO, or because of the high degree of cropping I'm having to do. So I'm going to up the lens in order to reduce the amount of cropping required. I'll also consider buying a Canon lens to see if the quality of the lens makes any difference.
I find it truly remarkable that this butterfly was once really quite restricted in its distribution and threatened in the UK. Luckily it seems to have benefited greatly from warmer temperatures and is now able to take advantage of a wider range of food plants in newer parts of the country.
I noticed two apparently male Brown Argus behaving oddly. The front one, smaller, and a lot less worm was apparently displaying mate refusal signals. He/she was quivering his/her wings and had pointed the tip of the abdomen vertically upwards in what I believe is known as the mate refusal posture, normally exhibited by mated females who "wish to be alone". The two remained in this sort of position for about a minute before the rear one flew off.
It then took about 10 seconds for the front one to stop its quivering and posturing, and then it eventually flew off as well.
Where am I going wrong? Were they both really males, as I interpreted the wing patterns, in which case why was the front one exhibiting mate refusal posture? Is that normal behaviour for males to do?
Or was the front one actually a female, with the orange spots not quite reaching to the front of the fore-wing? In which case how accurately can one really identify gender in Brown Arguses, including that of the rear one in these photos?
The Brown Argus is on its second brood, by a couple of weeks. It should be egg-laying and I would hope to see females fluttering about at low level looking for lush shoots of Rock Rose, Helianthemum nummularium plants to lay on.
As yesterday, there was one gorgeous Small Copper, Lycaena phlaeas, to be seen. This one was actively feeding on Marjoram, Origanum vulgare (L.), probing different flowers on one head very busily. I could not tell whether this was a male or a female, although I would have thought it might have had more rounded wings, making it a female. The subspecies found in the UK is Lycaena phlaeas eleus, first defined by Fabricius in 1798 in Germany, as opposed to the type named in Sweden. Amongst other things he described the antennae as brown, white ringed, with a black, oblong club, tip rust-coloured [although the base of the antennae actually looks white on the underside, on the basal half, as seen in the second picture]. Its really nice to see the copper hairs on the frons, and the dark chocolate brown of the eyes.
The primary larval foodplants are Common Sorrel (Rumex acetosa) particularly on calcareous soils and Sheep's Sorrel (Rumex acetosella) particularly on acid soils. Broad-leaved Dock (Rumex obtusifolius) is also used very occassionally - possibly when the sorrels are affected by drought. "Forewings dark brown with a bright reddish yellow discal region with large black spots, grey beneath with a reddish orange discal region with (small?) black eyespots. Hindwings greatly notched and generally twin-tailed, dark brown, with a bright band with short teeth, reddish yellow, grey beneath with minute black spots and a faint reddish yellow outer band" (Fabricius, 1798).
Today I must have seen hundreds of Meadow Browns, Maniola jurtina, all of which seemed to be feeding on the abundant nectar sources available. Here is a nice female on Wild Rosemary:
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