3 replies to this topic

[mattknepley]

(with apologies to Kim Carnes)


A couple summers ago Gerald and I had a little sidebar about the usefulness of Carolina Darter eyes as a field identification aid, specifically in regards to distinguishing them from Swamp Darters. We noticed that Carolina Darters' eyes possess a funky "reflective-opaqueness".

I snuck out for a little stream time yesterday, and remembered our conversation after dipnetting a female E. collis.

Roper's Creek (I think), Greenwood Co., SC

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Air temp = 33*F Water temp = 44*F A perfect day for field work.

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The eyes have it.

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A couple pics with some Greenhead Shiners in the same lighting conditions for comparison.

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Ventral spot to verify scaleless breast and E. collis identity.

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Did I mention I had previously shredded my neoprenes?

[fundulus]

You're right, those eyes are really unusual. And I salute your thermal tolerance....

[gerald]

Sort of a greenish-gray haze on the cornea, similar to black seabass and other fish that are dusk/dawn active.  Maybe it has some dim-light vision significance in E. collis, either for feeding at dusk/dawn or in dark spaces under leaf litter?  

[Isaac Szabo]

Interesting observation on the eyes. I'm not sure I've ever seen that in darters.