Thursday, 16 May 2013

Egg laying Footballer hoverfly

Footballer hoverflies are commonly seen near water: ditches, ponds and drains, their genus name Helophilus, actually means 'lover of marshes' in Greek. On a little twig over a puddle on the pavement by a busy road, two Helophilus pendulus females - their abdomens large and turgid with eggs - laid. While one of them was busy actually laying under the twig, the other seemed to be 'feeling' the twig with the ovipositor, probably selecting the best site to lay her shiny white eggs. Note the ovipositor stretched out. Helophilus lay their eggs on clumps - like bluebottles - unlike other hoveflies which lay individual eggs singly. This might well be due to their different feeding habits. Many hoverfly larvae are predatory, and being born away from hungry siblings might give them a better chance to find food (like aphids). Helophilus are related to Droneflies, and their larvae, called rat-tailed maggots, are aquatic, and develop on very wet manure or submerged rotting organic material often in large numbers, so they are less likely to compete for food. Their 'tails' are actually long telescopic breathing tubes, that they can retract into their bodies.
 For a great series of shots of Helophilus egg laying and larvae development check BugGuide.
Another shot of the laying female
I turned the twig to reveal the egg clutch after the female lad left. As they lay under the twig, the eggs are not readily visible.


Sunday, 12 May 2013

Fangs!

A rainy day, I look around the house for things to look up with the little digital microscope and I find the shrivelled shell of a spider, probably a Tegenaria, in the conservatory, behind a pot. I notice the fangs and look under the microscope. It is not the best photo, but I am quite pleased with the fact that the tiny openings at the end of the fangs (where the venom comes out) are just visible. Click here for a scanning electron photograph of these openings. The fangs act as hypodermic needles, injecting the venom inside the prey's body. The teeth that help hold the prey while the venom is injected are visible at the bottom.

Adult pair of Pholcus phalangioides

 In the last few days, I have been keeping an eye on a pair of Pholcus phalangioides in my outside toilet. They are a male and a female, and given that both appear to be adults I guess the male is waiting for the female to become receptive. I got a close up of the male, showing its almost circular caparace and its palps (above).
Pholcus phalangioides. Male on the right, not its elongated abdomen. 

Tuesday, 7 May 2013

Black Lace Weaver: the female

Not even a week after finding my first male Black Lace Weaver, Amaurobius ferox, I came across the beautiful female by the back door mat of some relatives. The previous day I had seen a very fresh dead, limp male - which now I believe had just had a fatal encounter with the female - and possibly disturbed the female from feeding on its corpse. I checked the palps and left the corpse where I found it. The following day, on the same place where I had found the dead body of the male, I spotted the female, indoors. I took more photos of her, velvety black, fresh, alert. She moved across the room in broad daylight, and fearing for her life, I took her outside to a safer place.
A view of the top of the female, showing how dark it is and the faint markings of her abdomen
Crouching by a chair leg
A 'habitat' shot
Later, I spotted the body of the male, this time wrapped in cribellate silk, its skin empty like a discarded sweet wrapper. Were both wandering in search of mates, what was she doing out in the daylight, far from her hiding hole? 

Saturday, 27 April 2013

Red Ant nest

We found this Red Ant, Myrmica sp., nest under a stone. The chamber in the middle of the photo had many workers tending larvae, and what appeared to be a queen, a bit larger with darker head on the top left corner. With the ants, there were a few Cyphoderus albinus, a species of white springtail which is often found inside ants nests. There were also many millipedes, thread-like, blind, with red spots, Blaniulus guttulatus.
Blaniulus guttulatus millipede
White springtails, millipedes, red ands and a slug