Sunday, 21 April 2013

Bit of a Fly, Tachina ursina and a bit of a Weevil, Barynotus obscurus

Barynotus obscurus - Carlton Garden, Nottinghamshire 21st April 2013  
Brushing up a few leaves in my back yard this Sunday morning and swept this little beast up. Not quite your run of the mill vine weevil but another species of broad nosed weevil Barynotus obscurus. Interesting facts about these beasts are that no known males have ever been found in the UK, they are parthenogenetic (asexual reproduction in which embryonic development occurs without fertilisation). Pretty common in most herbaceous lowland areas but never found in large numbers. I generally find the odd one in my Carlton garden most years but never several in a year. I suppose if you are parthenogenetic you don't need to go looking for a mate so don't need such high densities in order to survive. Interesting parthenogenesis also occurs in vertebrates, notably some species of lizard and fish but also in some birds.   

Tachina Ursina - Budby Heath April 20th 2013

I'm not that hot on flies but this chap caught my eye while out and about yesterday, Tachina ursina, don't think it has a common English name, not that I'm too bothered about that one.  If you like flies you'll probably learn the correct latin names and just be a little bored with stupid made up English names with no relevance to their lifestyle or habits. Don't know the lifestyle of this one but if it's anything like other Tachinid flies they usually lay their eggs on lepidopteran larvae.  The Maggot then eats the fat deposits of its host until its ready to pupate. Nice!