Is this a false widow?

[faz]

They have a dark shiny body. The abdomen has some pale markings on the top, and there is a creamy coloured band all round the front. Under a hand lens this looks like an intricate mosaic.

[MattPrince]

Originally Posted by faz

They have a dark shiny body. The abdomen has some pale markings on the top, and there is a creamy coloured band all round the front. Under a hand lens this looks like an intricate mosaic.

Now you mention it - a lot of spiders have this mosaic affect, the common hammock weaver - linyphia triangularis, for example, when viewed up close, the white bands are exactly as you describe. Same affect with meta(llina) species when viewed under the 'scope.

Makes me wonder if this is a symptom of the structure of the abdomen surface - perhaps some of the flexibility in the abdomen comes from having stiffer plate like areas linked by softer areas - which contradicts my current understanding of the abdomen skin as a "simple sack". Have to see if I can find the structure of the abdomenal cuticle covered in depth anywhere...

The more I know .. the less I know!

Cheers,
Matt

[MattPrince]

Well my current understanding was woefully off - a spiders abdomen is, like other arachnids, segmented. In a spiders case the tergites and sternites are mostly hidden from view by the external sack like cuticle.

Still wonder if the common mosaic patterning shows up some structure of this cuticle though...

Cheers,
Matt

[faz]

Originally Posted by MattPrince

Well my current understanding was woefully off - a spiders abdomen is, like other arachnids, segmented. In a spiders case the tergites and sternites are mostly hidden from view by the external sack like cuticle.

Still wonder if the common mosaic patterning shows up some structure of this cuticle though...

Cheers,
Matt

thanks for the info