Tetragnathidae ID

[Action_Man]

Im my garden, no water for miles around, around 12mms long ...

[mickmassie]

It's a male, but I guess you'd know that. The key palp characters aren't visible to my eyes but someone with more experience may be able to help. Mick.

[No.9 Spider]

Unfortunately that's a no from me too . Fantastic photograph though.
As with epigyne details, palpal details are drawn from a precise position, and a minute fraction of a degree out of that position drastically alters the detail you see in comparison to the i.d. drawing.
For Tetragnatha you need to see the tip of the palpal organ in a view that's basically from between the palps looking outward to the inside of the palp (usually right palp as you look down on the spiders carapace - dorsal side). A view of the sternum can narrow the options in this species also.
(That may not be too clear a description?)

No.9 Spider

[Action_Man]

So with the angle its at now, i need to move the focal plane towards the other palp ?.

Are there any British Tetragnathidae not associated with water ? ...

[No.9 Spider]

It's the right (correct) palp, just that the photo needs to be taken from the other side, i.e. from between the palps looking out?

Below is just a sample (top photo), not the species in question.

http://www.jorgenlissner.dk/images&#...L5544_az77.jpg

Some palpal features for other spiders require different or additional views. There are a few Tetragnatha sp. that are not restricted to or solely associated with water.



No.9 Spider

[No.9 Spider]

Habitats as given in Roberts are as follows:

T. extensa – close to water/boggy habitats
T. Montana - sometimes near water, but also occurs further away from water than T. extensa
T. pinicola – often away from water (rare and uncertain records)
T.obtusa - damp woodland
T. nigrita – generally on trees (rare)
T. striata – reeds/vegetation in or close to water (rare)

T.extensa and T. montana are by far the commonest of the species. The sternums of Tetragnatha can be used to a degree to separate into two groups. T.extensa and T. pinicola have a distinct light mark thru' the centre of the sternum whereas the other species have a uniform dark sternum lacking this lighter band.
Your specimen could be T. montana from the habitat info and would therefore also lack the light band on the sternum.
Palpal details however are the best determiner in my opinion.


No.9 Spider

[Action_Man]

Thanks for all the additional information No.9, much appreciated, if i see this again i will try and get some palpal shots ...