Sex these ?

[CedrikG]

Heya all, early I came with a water spider in a pcture and asked for the species, i've got 3 now and I would like to know species and sexe IF POSSIBLE, I would likew to try a breed, soo here they are :

 

[Christoph]

Hi,
1) Female

2) Female

3) Male

 

[CedrikG]

same species ?

 

[Christoph]

I'm not sure where thy come from?

 

[CedrikG]

from quebec

 

[CedrikG]

ok, and you think I should try an attempt ?

 

[Spaceman_Spiff]

Do not try to breed them, to me they look like different species!
The spiders in the first two pictures look like Dolomedes tenebrosus and the third could be D. triton.
And secondly, you cannot really determine their sex with these pictures.
Try to look at their underside, if there is a sclerotized, structured area on the abdomen (called "epigyne", try googling), it is female.
A mature male could be recognized by it's swollen palps.

regards
Bernhard

 

[CedrikG]

is it like a tarantula ? If so I can sex them

 

[Spaceman_Spiff]

Hi

It is the same area as with tarantulas, but "higher" spiders, such as Pisauridae have developed a structure over the female genitalia that works like a lock, in which only the pedipalps of a male of the same species fit perfectly. It looks different from a female tarantula's epigastric furrow.
The structure is called "epigynum"or "epigyne" and is missing on a male spider, so immature males can be recognized by the absence of it.
However, mature males do have swollen palps, very similar to a male tarantula's.

The epigynum looks different in every species of spider and is in fact one of the most important taxonomical traits in "higher" spiders.

I tryed googling for "epigynum" for pictures, haven't found pictures for Dolomedes species though:
http://images.google.de/images?q=epigynum&hl=de&btnG=Google-Suche