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Black Darters From North Alabama


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#1 Guest_fundulus_*

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Posted 10 November 2006 - 10:10 AM

Here are some black darters, Etheostoma duryi, from Swan Creek on the north edge of Athens in Limestone County, Alabama. They were captured in early April, and are freshly euthanized. The top two are females, the bottom one is male. The male is about 55 mm SL. You can see the genital papillae on the two very gravid females.

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#2 Guest_drewish_*

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Posted 10 November 2006 - 10:51 AM

Nice looking fish. Were they used for a study or used for an ID collection?

#3 Guest_fundulus_*

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Posted 10 November 2006 - 03:25 PM

Nice looking fish. Were they used for a study or used for an ID collection?


I kept them as a voucher for that time of year in that stream. One of my students is doing a research project comparing black darter reproduction in two local streams in Limestone and Madison Counties, AL, and Swan Creek is in the same general area. One odd result we have so far is that the black darters in the two creeks are very different in size; the ones from a semi-eutrophic creek running through downtown Athens, AL, are much bigger than the blacks we collected in a cleaner rural stream in Madison County near the TN line. I'm waiting to see the reproductive efforts results tabulated, i.e. how many eggs they produce when in the spring, etc.

#4 Guest_nativecajun_*

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Posted 09 December 2006 - 04:59 PM

Interesting fish. Do these look somewhat like the Tennessee Snub Nose?

#5 Guest_dsmith73_*

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Posted 09 December 2006 - 07:53 PM

Interesting fish. Do these look somewhat like the Tennessee Snub Nose?


Almost exactly like as a matter of fact. Fundulus will have to explain the intricacies of these.

#6 Guest_ashtonmj_*

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Posted 09 December 2006 - 10:03 PM

speaking of looking like simoterum...that top one has markings along the cadaul peduncle that are more simoterum like as opposed to your bottom fish which to me is a classic duryi. Aren't they sympatric there? I know in that middle bend of the TN draingage they are in some streams. Ulocentra's bother me especially when you have that sympatry and really brings into question "species".

#7 Guest_nativecajun_*

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Posted 10 December 2006 - 06:54 AM

Hey ashtonmj speak english I am not a scientist, I just like fish. I know I catch the tennessee snubnose here in Collegedale TN and I believe an integrade between the blacksided I think it is with the snubnose. So what are all those fancy words you said up there. You don't have to impress me just inform me and maybe I can learn.

#8 Guest_dsmith73_*

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Posted 10 December 2006 - 09:36 AM

What ashton was saying is that he thinks these fish may not all be black darters(E. duryi), but at least one looks like TN snubnose(E. simoterum) based one the marking near the tail fin(on the caudal peduncle). He also asked if these fish occur together in the same streams(sympatry). He said that snubnose darters(subgenus Ulocentra), in general, both him, especially when they are found together in the same streams, since they look so much alike. This brings into question whether they are in fact different species.

Just as a side, this is the way fish people talk a lot of the time. It is easier if we use more specific terminology to describe things. Just as I am certain there is a set of terms that deal with photography that get thrown around.

As a comment to your's Matt, I totally agree. I don't like the way so many species have been split based on arbitrary morphimetric markers. We can't always get a nuptual male to make a determination form, not can we always get a sample of DNA. I think fish should be readily IDable in the field based on good solid markers. I seem to be in a growing minority here though.

#9 Guest_ashtonmj_*

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Posted 10 December 2006 - 11:30 AM

Exactly. I don't see fused blotches enough on the first specimen and a slightly broader snout to convince me it is a duryi and if I recall correctly they are found together in that area of Alabama which is I'm guessing Paint Rock or Flint river drainage into Guntersville. I totally understand why species in the Ulocentra subgenus like E. prryhogaster, etneri, flavum, others outside the TN drainage are solid species, but I just see duryi as ecomorphs or variation.

I consider simoterum and duryi to be more like 'clinal effect' seen in mussel species as they change forms from a headwater species to a medium stream to a large river. You can find multiple morphs sometimes at one site too. The Ulocentra species from the middle of the Duck River is a great example of this. There isn't even a consensus within aquatic species on how to define 'species'. With the the catspaw mussel, which is a species or subspecies depending on who you talk to, does not occur sympatrically that I know of, but is only seperated on the basis of the color of the inside of the shell. Well then why isn't Elliptio dilatata and Pleurobema sintoxia 3 species based on nacre color and even varying external morphology that can occur together and seperate. I guess I really just wish there was a wonderful week long taxonomy and systematics conference, everyone gets together, and says okay as of now unless we find a better way this is what we are ALL using as criteria acrossed all taxa the best way possible. Mussel taxonomy is absolutely destroyed and is in the process of taking a generation or two to fix the problems because there was no consensus.

Where is Collegedale Tennessee?

#10 Guest_fundulus_*

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Posted 10 December 2006 - 10:42 PM

OK, I'm back from the weekend... The three fish in my photo are two females on top, and a male on the bottom. I'm totally certain that the male is duryi by any standards. In my experience the females don't have the same consistently fused dorsal saddles forming a line down the side, which is to say that they might look like a formal description of simoterum. I'm going with the interpretation that all of the Ulocentra darters in this creek, that drains directly into the Tennessee, are duryi simply because all of the males look right (this includes frenum or no frenum on the snout, and red dots on the body).

The one place where I'm certain I've seen sympatry between simoterum and duryi is in Hurricane Creek in the Walls of Jericho reserve. This is an upper tributary to the Paint Rock flowing out of Tennessee into Alabama, as Matt mentioned could be of some interest. I think the general breakdown would be simoterum is more typical in highland streams, and duryi is more typical of lowland streams with a direct connection to the Tennessee. This has been borne out in my experience of looking at lots of these darters from Limestone Creek in Madison County, AL, which I would describe as duryi based on the degree of lateral dorsal saddle fusion (especially in males) and the extent of the snout's "snubbing", and the same is true with fish from Town Creek in downtown Athens, AL, which I would also describe as all duryi for the same reasons. Both of these creeks also flow directly into the Tennessee. Does this mean that all lowland stream Ulocentras in my area are duryi? I'm not entirely certain, but it makes more sense to me. Brady Porter at Duquesne University has mentioned that in his experience Ulocentra species are not generally sympatric (he may have said something stronger). I tend to agree.

Exactly. I don't see fused blotches enough on the first specimen and a slightly broader snout to convince me it is a duryi and if I recall correctly they are found together in that area of Alabama which is I'm guessing Paint Rock or Flint river drainage into Guntersville. I totally understand why species in the Ulocentra subgenus like E. prryhogaster, etneri, flavum, others outside the TN drainage are solid species, but I just see duryi as ecomorphs or variation.

I consider simoterum and duryi to be more like 'clinal effect' seen in mussel species as they change forms from a headwater species to a medium stream to a large river. You can find multiple morphs sometimes at one site too. The Ulocentra species from the middle of the Duck River is a great example of this. There isn't even a consensus within aquatic species on how to define 'species'. With the the catspaw mussel, which is a species or subspecies depending on who you talk to, does not occur sympatrically that I know of, but is only seperated on the basis of the color of the inside of the shell. Well then why isn't Elliptio dilatata and Pleurobema sintoxia 3 species based on nacre color and even varying external morphology that can occur together and seperate. I guess I really just wish there was a wonderful week long taxonomy and systematics conference, everyone gets together, and says okay as of now unless we find a better way this is what we are ALL using as criteria acrossed all taxa the best way possible. Mussel taxonomy is absolutely destroyed and is in the process of taking a generation or two to fix the problems because there was no consensus.

Where is Collegedale Tennessee?



#11 Guest_nativecajun_*

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Posted 11 December 2006 - 09:17 AM

I looked in my field guide and could not find a darter called black darter. Black sided darter I did find. A big solid black line down the side of it. Now did things change since my field guide was published, because it is quite old. And about those photos I believe it is only the Tennessee Snubnose that has that little "snubnose" that turns green in breeding colors and not the black sided. Now am I right about the black sided's name being changed or did I just overlook the black darter in my book. I did not take note on who explained all that terminology to me but thanks very much. I doub't I will learn all that stuff at my age but who knows miracles do happen LOL. And about the photography thing I suppose I could throw out quite a few words that most would not understand in the fish world. So appologies for that. Take care and merry Christmas to all and their families. Daniel

#12 Guest_nativecajun_*

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Posted 11 December 2006 - 09:29 AM

" Where is Collegedale Tennessee" someone asked. Well as you go through Chattanooga heading to Knoxville going east on I 75 and you get off on exit 11, that is Ooltewah Tennessee. Well Collegedale Tennessee is Just south and east a little "like they are almost one town", I get my mail from Ooltewah's post office". It has a University there run by the Seventh Day-Adventist church. Used to be a very quaint little place not very busy at all. But as usuall things change. I think everyone from somewhere liked the quaintness of the place and moved here. Now we even have our own Wallmart (almost, it is being completed as I type) "groan, wine, grrrr". To put it in plain english I do not like it as much as when I went to school here from 79 to 82. If you saw one car at 9 oclock at night the traffic was heavy back then. Now the streets are busy any time of day or night. More so in the day, but I think I made my point. And Collegedale is home base for the most successful cookie/cake company in the US "Little Debbie" AKA McKees Baking company. Back in "the old days" the closest grocery store you had to travel 15 to twenty minuets to get to. Now we are bombarded with at least three dollar stores, Wallmart to be, Bi Lo grocery store and many many other resturants etc etc. I remember having to go all the way into Chattanooga to go to Taco Bell. And I talk too much. I hope I answered your question LOL. One more thing. We have a stream here in Collegedale that is very diverse in its species. Not so much now since the University has had so much construction years in a row and did practically nothing "groan, grrrr, mad scoff" to protect it from all the silt. The species are still there but not near as large as you used to be able to find and not near the numbers. I remember finding a Mottled Sculpin one time so huge that the friend I was with was laughing at me because I was so excited like a kid with a new toy. Rainbow darters, Tenn Snubnose, Black sided, all kinds of shiners and redhorses and dace. Really nice and handy and less than five minuets from my house. Anyone ever come this way look me up or let me know through this thingamobobby and I will show you where it is. But I am heading to Lafayette Louisiana in a few days and I plan on collecting at points everywhere inbetween here "Collegedale" and Lafayette LA.

#13 Guest_dsmith73_*

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Posted 11 December 2006 - 09:55 AM

I looked in my field guide and could not find a darter called black darter. Black sided darter I did find. A big solid black line down the side of it. Now did things change since my field guide was published, because it is quite old. And about those photos I believe it is only the Tennessee Snubnose that has that little "snubnose" that turns green in breeding colors and not the black sided. Now am I right about the black sided's name being changed or did I just overlook the black darter in my book. I did not take note on who explained all that terminology to me but thanks very much. I doub't I will learn all that stuff at my age but who knows miracles do happen LOL. And about the photography thing I suppose I could throw out quite a few words that most would not understand in the fish world. So appologies for that. Take care and merry Christmas to all and their families. Daniel


Even the most recent Peterson's guide is dated as far as many of the most recent splits are concerned. The snubnoses have been split a ton, down nearly to drainage. There is a new Peterson's coming out next year that should have all of these revisions in place. I would also suggest Etnier's Fishes of TN, which does a good job of classifying the snubnoses. The blacksided darter is a Percina sp. and looks very different from the Ulocentra snubnoses.

#14 Guest_ashtonmj_*

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Posted 11 December 2006 - 09:55 AM

Ah okay. I have spent oh a dozen+ trips off I-75 where TN route 60 intersects at Cleveland. That was my 'home' base whenever I electrofished or snorkeled the Hiwassee the past two summers since there really isn't anything else within 30 minutes of the river.

[quote name='nativecajun' date='Dec 11 2006, 02:29 PM' post='5791']
" Where is Collegedale Tennessee" someone asked. Well as you go through Chattanooga heading to Knoxville going east on I 75 and you get off on exit 11, that is Ooltewah Tennessee. Well Collegedale Tennessee is Just south and east a little "like they are almost one town"

I'll agree with 'generally' are not sympatric, but I don't know how much stronger you can go. There are at least 3 rivers I can think of off the top of my head where they are and one (the Duck) where things get really odd looking, and you have overlap beteween simoterum and flavum too. Then again, not all the Duck River is Highland, parts are Nashville Basin. Almost always exceptions and even exceptions to the exception.

When you describe your male female black darters Bruce it sorta leads one to the conclusion that if the female agrees with the traditional snubnose and a breeding male appears differently, that maybe we shouldn't be describing fish based on breeding male colors, which are extremes. Is lack of a frenum good enough to designate a species when there is overlap and possible/likely gene flow. That's like unattached or attached ear lobes. I'm just stoking the fire now in the context of a bigger topic :lol:

#15 Guest_dsmith73_*

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Posted 11 December 2006 - 10:21 AM

Matt, I like where you are going with this. It has always bugged me that these darters have been separated based on breeding male coloration, especially after seeing the very complex process that is undertaken to determine the actually chemical differences between the pigmentation. You should be able to look at a darter, preferrably in the field, but not necessarily, and know which species it is without having to extract the pigment or run a DNA sequence on it. I don't really consider myself a lumper or a splitter, but I do believe that there needs to be some common sensical mechanism to determine what a species really is that we can all adhere to. There is such division right now between camps that I don't think is necessarily good for nomenclature in general. I hate to think of species being such fluid entities. One day your a species and the next day you're not. This could be used to the detriment of imperiled fishes if there can be an argument that particular species are not valid and thus do not deserve protection.

#16 Guest_fundulus_*

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Posted 11 December 2006 - 03:15 PM

When you describe your male female black darters Bruce it sorta leads one to the conclusion that if the female agrees with the traditional snubnose and a breeding male appears differently, that maybe we shouldn't be describing fish based on breeding male colors, which are extremes. Is lack of a frenum good enough to designate a species when there is overlap and possible/likely gene flow. That's like unattached or attached ear lobes. I'm just stoking the fire now in the context of a bigger topic icon_lol.gif

You're right about a feature as seemingly trivial as a frenum or not. But there are real differences in breeding male coloration, and generally females respond to and mate with the "right" male. One of my graduate students is doing a project looking at reproductive effort and timing by two black darter (duryi) populations, from Limestone and Town Creeks that I mentioned before. I spent a lot of time looking at the individual fish as we captured and processed them last winter/spring to make sure that they were really, truly, black rather than Tennessee darters. They all lacked a frenum, and the males all pretty much looked like my photo at the top of this thread. But the females varied from a pronounced lateral black band, to ones who had dorsal saddles lightly connected by a lateral black band. I'm going with the interpretation that they're all duryi. I'm happy to do so because you would expect a range of variation in a population/species; individuals aren't genetically or phenotypically identical. So there's no such thing as an ideal black darter.

I should say that we're going to compare our black darters results to work by David Heins (Am. Midl. Nat. 145:74-79, 2001 I think) studying simoterum from Lawrence County in south Tennessee, not very far to the NW of here. It may well be the case that we'll find more differences between our two black darter populations than between them and the two Tennessee's; an interesting result to date is that one of our populations is significantly larger in standard length than the other. How this translates into average ova per female is still being calculated. But if I knew all the answers already it wouldn't be research, would it?

#17 Guest_TomNear_*

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Posted 13 January 2007 - 10:23 AM

I have some insight on this isue that I can interject. E. duryi and E. simoterum are quite divergent when you consider how all of the snubnose darters are related to one another. All the genetic evidence presented to date indicates that the two species do not represent a cline. They are distinct lineages. For example, the snubnose darters most closely related to E. simoterum and E. atripinne (cumberland) are E. rafinesquei and E. barrenense.

Also, I just want to clarify that snubnose darters have not been split out of other species, they just have been described since the 1980s. The story is that some ichthyologists were sitting on the describtions for decades (just like the current bridled darters in Percina) until Larry Page and Brooks Burr fired the first shot and described E. barrenense and E. rafinesquei. To think of them as split out of other speices is not accurate.

The frenum character, first illustrated by Dave Etnier, seems to work really well in identifying E. simoterum, relative to E. duryi and E. flavum.

We have a large scale darter DNA sequencing project up and running in our lab. If anyone would like to double check their identifications with some genetics, just send me an email and I can send you a tissue sampling kit.

thomas.near@yale.edu

Best-Tom Near

#18 Guest_fundulus_*

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Posted 13 January 2007 - 11:21 AM

I have some insight on this isue that I can interject. E. duryi and E. simoterum are quite divergent when you consider how all of the snubnose darters are related to one another. All the genetic evidence presented to date indicates that the two species do not represent a cline. They are distinct lineages. For example, the snubnose darters most closely related to E. simoterum and E. atripinne (cumberland) are E. rafinesquei and E. barrenense.

Also, I just want to clarify that snubnose darters have not been split out of other species, they just have been described since the 1980s. The story is that some ichthyologists were sitting on the describtions for decades (just like the current bridled darters in Percina) until Larry Page and Brooks Burr fired the first shot and described E. barrenense and E. rafinesquei. To think of them as split out of other speices is not accurate.

The frenum character, first illustrated by Dave Etnier, seems to work really well in identifying E. simoterum, relative to E. duryi and E. flavum.

We have a large scale darter DNA sequencing project up and running in our lab. If anyone would like to double check their identifications with some genetics, just send me an email and I can send you a tissue sampling kit.

thomas.near@yale.edu

Best-Tom Near


Yeah, I remember seeing some of Brady Porter's mtDNA work showing surprising distance between duryi and simoterum, so it's not as easy as a clinal separation. Here in the southern bend of the Tennessee there seems to be a separation of the two species by habitat use as I've said before, with duryi as a lowland species and simoterum found in the highlands somewhat to the north, as evidenced by both frenum absence/presence and the less precise character of how solid a black lateral line is present. I'll probably take up Tom on his offer of genetic testing of individuals from some different streams to confirm my observations.




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