3 replies to this topic

[MichaelAngelo]

Hi All!

 

Here's one that we're leaning towards calling a Finescale dace, but I wanted to try and rule out Pearl Dace.  I know they can appear to be very similar or even hybridize.  

 

The Northern pearl has the herringbone line that this one has.  The finescale has the dark cape on the back and sides of the head that this one has.  For these two characteristics, each species is supposed to lack the other's.  

 

Mouth size is another differentiating characteristic, with finescale dace having mouths extending to "below eye".

 

Lateral line is supposed to be complete on the northern pearl and short on the finescale, but I can't tell from the pictures.

 

It was caught in a marshy lake in northern ontario by a beaver dam.  

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Edited by MichaelAngelo, 04 August 2015 - 03:29 PM.

[BenCantrell]

Don't pearl dace have bigger scales?

[Isaac Szabo]

I think the mouth size alone should make you pretty confident that they are finescale dace and not northern pearl dace. To me it seems that the mouth is too big for northern pearl. Also, I think the scale size and body pigmentation are more consistent with finescale than northern pearl. The only character in your list above that is pointing you toward northern pearl is the herringbone lines on the side. However, I can't figure out what Peterson Field Guide is referring to with this. If you look up photos of these two species, most finescale have what I would call a herringbone pattern along the side that is exactly like what your fish have, while northern pearl do not.

[MichaelAngelo]

Thanks for the replies guys, I believe I caught more finescale dace from another location and what they look like reinforces that this is a finescale.  Thanks again for the input!