Aviso: Some or all of the identifications affected by this split may have been replaced with identifications of Leucauge. This happens when we can't automatically assign an identification to one of the output taxa. Review identifications of Leucauge venusta 53467

Taxon split aaaaaa 48px Taxonomic Split 40418 (Guardado el 01/10/2018)

World Spider Catalog, Version 19.5 (Referencia)
Añadido por claggy el 28 de septiembre de 2018 | Comprometido por claggy el 01 de octubre de 2018
dividido en

Comentarios

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So, where does Leucauge argyra fit in to this, https://bugguide.net/node/view/40305?

Publicado por norm_shea hace casi 2 años (Marca)
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@norm_shea Nothing has changed for L. argyra, fortunately :)

Publicado por claggy hace casi 2 años (Marca)
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To attempt to clear up some confusion some may have: The southeastern states that have overlapping ranges between these two species had the existing IDs change to genus IDs. This graphic should give you an idea of the range split, so it mostly applies to areas closer to the coast and a little inland . I'll be going through and adding L. venusta IDs to observations in those states where the overlap likely doesn't apply.

Publicado por claggy hace casi 2 años (Marca)
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The article states, "L. venusta and L. argyrobapta are very similar morphologically, [...] with subtle differences observed in the male pedipalps [that] seem constant enough to allow morphological diagnosis of these two species [but] female specimens remain virtually indistinguishable on [a] morphological basis" and "[i]n most cases, geographic distribution can be used as a proxy for distinguishing these species as our results demonstrate that the geographic distributions of these species show little overlap." That doesn't seem to bear out in the graphic you reference for much of Georgia, South Carolina or North Carolina. In South Carolina the coastal section is unshaded, the Midlands appear to be L. argyrobapta and the Piedmont seems to be L. venusta. It would appear that identifications for both North and South Carolina and much of Georgia could really only go to genus, because otherwise it would have the possibility of erroneously representing the range for each species.

Publicado por norm_shea hace casi 2 años (Marca)
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@norm_shea Thanks for looking at this. I'm not entirely sure how to interpret the graphic, so I appreciate more thoughts on this. I can't see red super well, so in the unshaded areas I've been assuming they were more gradual or not shaded as dark, hah. Either way, I wasn't planning on adding L. argyrobapta IDs outside of Florida for now, and was going to leave the genus IDs where they are in the coastal sections of the states with overlap since they're a bit more confusing.

When it comes to L. venusta IDs, excluding NC & SC completely doesn't seem necessary to me (especially NC). I was thinking IDs would be pretty safe from around Raleigh and west of that (but not necessarily southwest) for North Carolina, but looking again, I think that may be too far east to be sure. Further west (such as Charlotte to Asheville) doesn't appear likely to have L. argyrobapta (unless there's some red there I can't see). South Carolina appears to be more covered with red, other than the northwestern tip. Georgia appears to only have red in the southeastern area, so northwestern L. venusta IDs seem appropriate to me.

Publicado por claggy hace casi 2 años (Marca)
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I had assumed the graphic was representing the actual range of where the spiders had been located, but rereading the text, now it makes more sense to me. Maybe you guys already got this. It's showing the combined "ecological niche models," or the suitable habitat for each species, which the authors say doesn't really overlap much at all. I think it's more helpful to view it in the report where they have it broken out into separated models. It makes the delineation a little easier to see. I'd be interested to see how many observations we have in the lighter areas.

Publicado por tigerbb hace casi 2 años (Marca)
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The map for argyrobapta strangely doesn't include the Texas coast, and the image that is presented for venusta actually looks like argyrobapta. Maybe you just haven't gotten to Texas yet??

Publicado por thebals hace casi 2 años (Marca)
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@tigerbb Thanks for clearing that up. That does make more sense.
@thebals I do see now that the main image appears to be from the border of extreme south Texas & Mexico, so I'll remove that one, thanks. But yeah, Texas is a question mark. It wasn't included in the ecological niche model graphic that I was looking at primarily (unless there's red there I can't see), but it does appear to be included in the other one on page 190, hmm.

So I guess now the question is, do we include Texas as well? All Texas IDs would need to be genus IDs then, I think, as the lighter areas on the graphic appear pretty spread out there.

Publicado por claggy hace casi 2 años (Marca)
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Here's the graphic that @claggy shared earlier with the state borders overlain, https://www.dropbox.com/s/22u29svfjpnutbe/Leucauge%20Range%20Map.png?dl=0. It was a difficult graphic to get to align so I focused on my primary area of interest, South Carolina. I'll again say that I think species level identification is going to be difficult for Georgia, South Carolina and North Carolina. I'm not sure what the large area of green covering the central and western part of Georgia represents but it doesn't appear that it will lead to definitive ID. And, there is what appears to be a verified L. venusta record in the red, L. argyrobapta geographic distribution area near the border of Georgia and South Carolina. I'm not sure how the claim can be made that "geographic distribution can be used as a proxy for distinguishing these species as our results demonstrate that the geographic distributions of these species show little overlap" when there are very few actual verified identifications along the transition areas and the ones that do occur there represent the incorrect species. This kind of leaves identification in a bit of a problematic state.

Publicado por norm_shea hace casi 2 años (Marca)
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Oh awesome, thanks for doing that! Much easier to see now. I don't know what the green means either, hmm. Anyone else know? You do make a good point, and it would certainly be helpful if they collect more samples to show a more accurate distribution (plus I'd be curious to see how it compared to the ecological niche models). The graphic abstract on page 190 appearing a little different certainly doesn't help either.

Publicado por claggy hace casi 2 años (Marca)
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On BugGuide.net we are moving all the ones with orange posterior dorsal spots, the ones that we used to call mabelae, into a likely argyrobata page. Interestingly this is giving us a nice coastal range from Virginia Beach to south Texas. Will be interesting to see if we find any that look like mabelae that are not along the coast.

Publicado por thebals hace casi 2 años (Marca)
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@redpandakitty also mentioned that Raleigh isn't considered a part of the coastal plains of NC (where the paper mentioned the range extends from), so maybe that distinction can help give an idea of where to draw the line with regards to NC L. venusta IDs? Though the L. venusta samples found in the red areas still make it a bit more confusing.

Publicado por claggy hace casi 2 años (Marca)
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@thebals Oh, interesting, so you think you found a pattern distinction? That would certainly help, along with knowing how far inland it goes. Maybe we should make an observation field for these different patterns on here to help keep track of that.

Publicado por claggy hace casi 2 años (Marca)
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On living specimens, it is relatively easy to see the bright red-orange pair of dorsal posterior spots which allowed us to call these mabelae in the past. On preserved specimens in alcohol, it is our understanding that these colors fade which has caused confusion. We moved all the specimens with bright orange spots into a 'likely argyrobapta' page on BugGuide.net and then mapped the locations of those selected. You can see the submissions and the location map on BugGuide.net here: https://bugguide.net/node/view/1598625
We were happy to see that the orange-red specimens occurred in a coastal band from Virginia Beach to south Texas. That's not proof that these are argyrobapta, but a reassuring result.

Publicado por thebals hace casi 2 años (Marca)
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I had already wondered about the mabelae pattern as soon as the geographic delimitation was announced. So I'm glad to see the results are showing that as a strong possibility.

Publicado por tigerbb hace casi 2 años (Marca)
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Thanks for the info. I do see it now- cool! That map is great too- so far it appears to be lining up quite well with the ecological niche models, including the one that includes Texas (model B on page 190).

How does everyone feel about the addition of Texas to the L. argyrobapta atlas? Based on the model I mentioned previously that does include it.

Publicado por claggy hace casi 2 años (Marca)
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I think adding the Texas coast definitely makes sense.

Publicado por tigerbb hace casi 2 años (Marca)
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When it comes to the atlas, I think I'd have to add the state itself like I did with the other states, as exploding Texas would result in having to choose which counties to include.

Publicado por claggy hace casi 2 años (Marca)
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Ah, yes. That makes sense.

Publicado por tigerbb hace casi 2 años (Marca)
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Ok, I've created an observation field to use to identify Leucauge observations that have the orange posterior dorsal spots so that we can have a map on here similar to what @thebals are doing on BugGuide. You can view the observation field map here.

Anyone is welcome to help add the field to the appropriate observations if they can! I have not done too many so far, and I may have made some errors due to not being able to tell much of a difference between the yellows/oranges/greens, so please update ones that are incorrect if you see any (and let me know which were incorrect). In some cases, I put the value of "review needed", so feel free to take a look and update those ones if you can. I haven't done much of this yet, but adding the value of "no" is also useful info, especially in areas where L. argyrobapta or overlap is likely.

Publicado por claggy hace casi 2 años (Marca)
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This is great! Will be putting it good use. Thanks, Matt!

Publicado por tigerbb hace casi 2 años (Marca)
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Thanks for the discussion. I have ID'd all my coastal Mississippi Leucauge as L. argyrobapta from their geographic position and the orange posterior dorsal spots, but I don't have access to the original paper and would like to know what they have identified as an ecological niche differentiation. Can someone summarize that here?

Publicado por janetwright hace casi 2 años (Marca)
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@janetwright, I can share the research paper with you if you want to send me a message with your email address.

Publicado por norm_shea hace casi 2 años (Marca)
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Hi all- I've been slowly going through Leucauge observations by state and adding the observation field I created. I've gone from Texas to New Jersey thus far, and here is what the map looks like at its current state for the 'yes' field (make sure to have it on Map view). So far it is pretty convincing to me, but if it does turn out to be a visual distinction, it also means that Virginia will need to be added to the atlas as well, as it has multiple eastern observations with the possible argyrobapta morph. There aren't many Leucauge observations near the coast of Maryland or Delaware, which I'd be interested in seeing more of.

Here is the current state of the map for fields marked with 'no', including California. I didn't really start including most of these until I was doing SC and NC, so there's still quite a bit to be done for this field.

Also, I am considering renaming the observation field from "L. venusta/argyrobapta - Orange posterior dorsal spots?" to "L. venusta/argyrobapta - mabelae morph?" (I'm open to other options/different wording). This is because I'm finding that the observations have the orange posterior dorsal spots also appear to have different ventral markings (as an example, compare this and this), and it is helpful to pay attention to into addition to the posterior dorsal spots. The current obs field results would not need to be changed due to how consistent it has been thus far. Any thoughts on this?

Publicado por claggy hace casi 2 años (Marca)
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@janetwright Were you able to get a hold of the paper? I don't think I can summarize it myself, but the paper is available to download for free from here by clicking on the PDF icon to the left of 'Show included taxa'. You do need a WSC account, but that is also free.

Publicado por claggy hace casi 2 años (Marca)
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Thank you, @claggy, @norm_shea sent it to me. I had thought the two species might be using different habitats more or less sympatrically, but the ecological niche differentiation was based on factors that were largely geographical. I was glad to get the details, though.

Publicado por janetwright hace casi 2 años (Marca)
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Ok great! Thanks for doing that, Norm.

Publicado por claggy hace casi 2 años (Marca)
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@claggy, wow, that's a lot of work! Really appreciate you dedicating the time to it. Two things I'm stuck by; first, how far north the "L. venusta/argyrobapta - Orange posterior dorsal spots?" observations go in Louisiana, almost to the Arkansas border. I wonder why that is? It is solidly in L. venusta territory from the habitat map. And why the lack of records directly east of that in Mississippi and Alabama, just a lack of iNaturalist observers or is the species not present?

Secondly, odd that there is such a cluster of L. venusta in North Carolina and relatively little representation in northern Georgia, Alabama and Mississippi (https://www.inaturalist.org/observations?place_id=any&taxon_id=778499). Is it, again, lack of observation or lack of occurrence? The same, if you just look at Leucauge genus (https://www.inaturalist.org/observations?place_id=any&taxon_id=53466), some interesting gaps in representation.

Altogether, very interesting, though.

Publicado por norm_shea hace casi 2 años (Marca)
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I should've mentioned that the 'no' field still requires a lot more work, as I didn't really start adding the 'no' ones until I got to SC and NC (edited prev comment to add that now). I will be revisiting the other states to add those soon.

I'm pretty much caught up with the 'yes' ones in the states I most wanted to look into, so it should be as 'complete' as it can be in those states minus new observations and the ones marked as 'review needed' (and just anything I missed of course) other than Texas (only done one page of Texas so far) and Florida. I was also quite surprised to see such northern Louisiana ones with the orange spots too. There aren't many Arkansas observations (only one southern one unfortunately), so I just went through those real quick and there were only a few that could use review.

That said, yes, some states have very few Leucauge observations. Some with like 20, others with hundreds.

Publicado por claggy hace casi 2 años (Marca)
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Because of all the rivers meeting in Louisiana, you can make it all to way up to Arkansas without hardly getting above 200ft in elevation. That doesn't happen in Mississippi and Alabama. So almost all of Louisiana is coastal in some sense. Not that we know that it makes a difference to the ecological choices of the spiders, but it does make Louisiana very different from its neighboring states.

Publicado por thebals hace casi 2 años (Marca)
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@thebals, interesting, I have to admit to not being that familiar with the topography of those two states. Maybe there is something to the elevation/habitat thing!

Publicado por norm_shea hace casi 2 años (Marca)
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Interesting point, thebals! That certainly could make a difference. It would help if we had more data for Mississippi, as there are currently only 30 Leucauge observations in that state. Even less in Arkansas.

Publicado por claggy hace casi 2 años (Marca)
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I have put out a call to the Mississippi Naturalists Facebook group to urge them to add Leucauge observations. Hope that yields some data points!

Publicado por janetwright hace casi 2 años (Marca)
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Awesome, thank you!

Publicado por claggy hace casi 2 años (Marca)
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I'm pretty much finished with going through the observation backlog of the states I wanted to go through and add the observation field to now. A couple of interesting finds:

-Possible L. venusta observations in northwestern Florida- 1, 2, 3, 4, 5

-Some of the possible L. argyrobapta specimens in southern Texas have slightly different ventral markings, often including a central line leading to the epigynum. 1, 2, 3

Now I'm wondering if there is a way to combine the 'yes' and 'no' maps, and make the 'yes' dots red and the 'no' dots blue, or something like that. I'm guess not, but it would be nice to be able to see them together like that.

Publicado por claggy hace casi 2 años (Marca)
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@mccreedy reminded me that some of the observations marked with 'likely argyrobapta' are still RG with L. venusta IDs, so I'm currently going through those observations adding disagreeing genus IDs to attempt to bump them to Needs ID. Mostly Texas, and some Virginia. My apologies for the ID spam (to those affected), as it wouldn't have needed to be done in this way if I hadn't made the mistake of excluding Texas from the atlas initially.

Publicado por claggy hace casi 2 años (Marca)
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Appreciate your work on it!

Publicado por tigerbb hace casi 2 años (Marca)
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Just noticed that I managed to miss Washington DC when adding states to the L. venusta atlas. Those observations were automatically bumped back to genus with the split as a result. 🤦‍♂️ Adding L. venusta IDs back to those now.

Publicado por claggy hace casi 2 años (Marca)
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Attempting to revive this discussion somewhat- I've been sticking with Leucauge IDs in most cases where there is possible overlap still. It seems that BugGuide is separating them mostly based on the visual distinctions discussed here these days (outside of a couple trickier ones that might be misplaced?). Was there further discussion at some point over on BG, @thebals?

Publicado por claggy hace 4 meses (Marca)
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There may have been some, but I don't recall offhand. There's no special notes on the info pages. Seems like they are being separated by color and that pretty much separates them geographically except for a couple coastal images in North Carolina and Louisiana. The images from California are sitting at the genus level. Seems folks aren't sure what to make of them.

Publicado por thebals hace 4 meses (Marca)
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It does seem like the visual distinction does separate them pretty well, or at least matches with the ecological niche model in Ballesteros & Hormiga 2018 quite well. It's quite interesting to see the similarities between the ecological niche model in the paper and the observation field map!

Publicado por claggy hace 4 meses (Marca)

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