B15DVE's picture

Common or Ruddy Darter?

Observed: 19th August 2010 By: B15DVEB15DVE’s reputation in Invertebrates

Darter, hard to tell, even with Id book whether its a common or ruddy. It appears to be more like ruddy in the book. Would appreciate knowing which one i have!

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RoyW's picture

Common Darter

This is a male Common Darter.

These can be very bright red when fully mature (although the colour is rarely as deep as that of Ruddy Darter).
If you look closely at the legs you can see that they are not black. It's not easy to see that there is a pale stripe along the legs, but they do look pale (the legs of Ruddy Darter are always black - but beware of reflected light!).

As, mentioned in the ID revision, Ruddy Darter also has a different abdomen shape. This can sometimes be a difficult feature to use until you are used to it, but viewed from above the abdomen of Ruddy Darter is usually obviously narrower in the middle than at the end.

This observation shows the black legs, and the abdomen shape, of Ruddy Darter quite well:

B15DVE's picture


...Roy, much appreciated! suprised no one picked up the spider and ID'd that for me !

RoyW's picture

It obviously wasn't the subject matter...

...but since you asked, it looks like Pisaura mirablis, the Nursery Web Spider (it's not my subject though so don't hold me to that!).