Metellina - which are about now

[MattPrince]

Hi all, I though it would be interesting to know which of the two metellina species (the "spring" mengei, or the summer "segmentata") are about at this moment in time.

Its been so mild I'm still finding good number of metellina sp whenever I bash dead bracken, tussocks or pretty much any vegetation, moreover there are still some in webs. I was sort of thinking they might be late overwintering segmentata.

The adult male m. mengei in this photo was beaten from dead bracken at a Dartmoor woodland on the weekend, I took it home, forgetting that adult male metellina can be done in the field with a hand lens or spy pot.



It's a (rather poor quality I'm afraid) photo grab through the microscope of metatarsus I - you can see a bit of debris caught in the long dorsal hairs that Roberts uses as a character for splitting out m. mengei from m. segmentata. Just about visibile with a x10, x20 or spypot.

[MattPrince]

Anyway.. the point is.. what are people finding at this point in the year?
Mengei? Segmentata? Dont know?
Cheers
Matt?

[MattPrince]

Then to confirm my suspicions about both being present this metellina segmentata female beaten from heather in E Devon.

Note Roberts suggests the dark midline abdominal band can be used as a character to seperate the two species in the field, however some experienced arachnologists Ive spoken to have cast doubt on the reliability of this character. In theory the dark band does not go forward of the epigyne in m. segmentata but does in m.mengei.

In my specimen there is a slighy suggestion of a dark midline band but not as clear cut as it would be in m.mengei. The epigyne projected over the epigastric fold and the dark line curling along its margins clearly fits segmentata.

Matt

[Jason Green]

I can't help with the ID, I'm just posting really to say it's good to see such rigour applied to the identification process.

[Geoff F]

Yes Matt, I agree that your comment of . . .

In my specimen there is a slight suggestion of a dark midline band but not as clear cut as it would be in m.mengei. The epigyne projected over the epigastric fold and the dark line curling along its margins clearly fits segmentata.

Clearly fits with the Roberts illustration (p 308) for M. segmenta. At least as far as I can understand the differences, but I'm not an expert.

[MattPrince]

Originally Posted by Jason Green

I can't help with the ID, I'm just posting really to say it's good to see such rigour applied to the identification process.

Thanks Jason - I'm trying anyway

Originally Posted by Geoff F

but I'm not an expert.

Nor I, but this specimen was quite clear cut on which epigyne it matched (not as obvious from my photo as it was with the naked eye) - if only that was always the case!

On the issue of the midline band, a female mengei from Stefan Sollfors excellent eurospiders website definately has a much more clear cut dark line forward of the epigyne. Hopefully as we move into Spring I should encounter significant numbers of mengei to compare and contrast with.

Cheers,
Matt

[MattPrince]

Despite the recent cold weather another male m.mengei from another part of the same site as the first. This time identified in the field and released. several juvenile metellina including merianae var celata. also present.

[MattPrince]

..and more adult male metellina mengei from similar habitat (dead bracken) near Burrator. Again released back into the field. The only females found were subadult, so ignored.

Surprised to be finding this many mature adult mengei this early...

Matt