Redhorse ID

This fish was called a golden redhorse in the field; collected from Broad Creek below Lake Aaron Strauss. However, Golden redhorse are not found and have never been reported (at least to my knowledge and through literature) from the lower Susquehanna River basin. This is the only picture of the only specimen collected. Shorthead redhorse are frequently found in the area. Opinions please.

Edited by ashtonmj, 07 April 2010 - 09:12 AM.

It certainly looks more shorthead-ish than golden to me by overall head shape. The best way is to looks at the lips. The lips of a shorthead should be relatively straight as compared to the more angled lips of the goldens. Both have 41-45 ish lateral line counts (yours looks to have 42), so that doesn't help.

Added: I think the dorsal and caudal fins seem to have 'sharper' points in shortheads, but then again, that doesn't help much. Sorry about that.

Edited by UncleWillie, 07 April 2010 - 09:31 AM.

Head length (measured on your photo) is about 22% of SL, which is on the longish end of the range for shorthead. I presume you've seen other Susqehana shortheads, and this one just aint right? Not much red in the fins, for a shorthead. Golden looks like a good possibility. Send the photo to Jenkins?

Gerald I'm a step ahead of you; he's been sent the photo. One expert has already chimed in and waiting to hear from another. I will say that NatureServe reports Golden's from the lower Susq., but in recent months I've come to really have little faith in many of their records. For example, there is no documentation of this potentiall odd ball, off in space record which would almost certainly represent an introduction of the species in the species report. I'm not finding any unpublished documentation either. Willie, unfortunately no lip picture. Whomever took it is going to get a stern ribbing because our protocols are pretty clear when taking photos that deterministic features be used. In this case, lips would have sufficed and this lateral shot is just eye candy. A jar would of sufficied too, but that is another story...

Thanks for raising those observations, Gerald. I need to pay more attention to things such as head-to-body ratios and the like. It is indeed hard to see if there is any red whatsoever on the caudal fin.
Matt, That is one thing I have learned when coming across something I don't know - take tons of pictures and get every possible feature you can that would help for identifying a particular species. While with some species, it my suffice to only take a lateral shot (some sunfish), but with something as Catostomids (in Georgia at least), a picture of lips is worth more than just about any other shots put together. Good luck with your findings, let us know what everyone comes up with.

I feel fairly confident that it is a shorthead. The shape of the head is not right for a golden, take a look at the following two shots.

golden redhorse head
 Golden Redhorse2 from the Kankakee River IN 06 29 07 by BZ.jpg   86.15KB   0 downloads

shorthead redhorse
 Female Northern Shorthead Redhorse Sucker3 from the Maumee River April 2007 by BZ.jpg   118.59KB   0 downloads

Jenkins gave me a nice email (below) for the multiple reasons without a specimen and the evidence he has why he would call it a shorthead. I was not at this site but based off of what little I can see of the lip, head/snout shape and length, and dorsal fin I was inclined to call it a shorthead. Zooming in on the picture does show some pigmentation on the dorsolateral scales too. May need to make a trip back to this site in a few weeks...


Fellows in Fishes,



Ah man… Next time lacking formalin, I advise pithing the spm or overdosing it in an anesthetic; keep it in a cooler (preferably with ice) until reaching the lab; freeze it until formalin arrives; pickle it good.



Head looks shortish to me; strongly declivous head dorsum and rounded (not deep) snout tip seem more like Shorthead. The visible bit of the lip seems somewhat small, hence Shortheadish. If the D fin margin is as concave-margined as it seems in the photo, this is more evidence of Shorthead and not Golden. Dorsolateral scale pockets (the anterior dark crescents, sometimes termed “scale-base spots”) are dark enough for Shorthead, but some Goldens have quite dark scale crescents too. Shortheads usually are “golden” (brassy) too.



The fish is an adult male based on the P2 fin having rather long inner rays, relative to the outer rays, and on incipient nuptial tuberculation. The fish seems prenuptial – tubercle development is incomplete on A fin rays, and a few tubercles are discernible on some P2 fin rays (C fin is obscured), but there seems sufficient development on these fins that tubercles should also show on the snout and cheek if the fish is a Golden; tubercles would be absent on the snout and cheek of a Shorthead, and that seems the case.



Am I seeing a tinge of redness on the distal half of the lowermost C ray? If yes, the fish would be a Shorthead. But I wouldn’t get excited if the C fin entirely lacked redness, which is common in adult Shortheads (especially those with the C fin being strongly melanistic) in some central (and south) Atlantic slope drainages.

I have struggled over this before in the susquehanna. Although some specimens were slighly questionable, all ended up being M. macrolepidotum. By looking at those pics, I see no reason that they are not shortheads.