Different Sceloporus species range in Mississippi?

I’ve been confused about this for a couple months now. What species of Sceloporus is the most present in MS? S. consobrinus or S. undulatus? Is there any consensus or should they just be labeled as genus? The RG observations make zero sense to me. These obs are both from Oxford, MS:
https://www.inaturalist.org/observations/292677
https://www.inaturalist.org/observations/6717461
For what reason is one labeled S. consobrinus when every other obs nearby is S. undulatus?
The RG obs overlap in Hattiesburg and the coast, but there are no spillover observations anywhere along the AR/MS border, but there is one on the LA/MS border? I’m hoping for someone to chime in so I can be more informed on my personal observations as I travel to different areas of the state.

I thought this said Selasphorus…

Out of the latest Peterson Field Guide, the eastern populations of S. consobrinus are indistinguishable from S. undulatus. While this book is country-wide, and thus the range maps are never as detailed as state books, I am unaware of a “Reptiles of Mississippi” book; certainly not one that post-dates the reclassification of many of the Scelop’s. Nonetheless, the entire state is S. consobrinus except for a slim portion along the NE border, from approximately Noxubee county, to Alcorn county.
With all that said, these range maps are not going to be based on any solid specimen analysis. There is likely a decently broad area of hybridization/integration/overlap (impossible to say which term is most appropriate without the data) that is just unknown at this time. I would thus not place a solid iNat ID on Sceloporus records in that part of the state.

A place to contact for better information than I can offer is your state university. U of southern Mississippi appears to have a decent program, but others probably do as well. It appears MDWFP might actually have a good baseline on this topic as well. https://www.mdwfp.com/museum/seek-study/biological-collections/amphibians-reptiles/

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From what I can tell after searching the literature is that researchers are having difficulty determining the species boundaries–even with some fairly rigorous genetic work. The most recent relevant paper I can find is this one: https://academic.oup.com/sysbio/article/58/6/547/1633600 (it has a map, but these maps often have a fair amount of speculation in them). I agree that they should be left at genus. The colored polygons on the map in this paper should be erased because their boundaries are not based on genetic samples. What you’re left with are colored DOTS with hundreds of miles of unknown between them. There is ONE sampled individual from the entire state of Mississippi. How can one draw conclusions regarding species boundaries within a state based on ONE sample?

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Yes, the paper @pfau_tarleton highlighted is the most recent genetic work in the region I believe. The newest major Scelop paper (the genome: https://www.biorxiv.org/content/biorxiv/early/2020/06/06/2020.06.06.138248.full.pdf) doesn’t even include consobrinus.
The most we really know is that consobrinus is present in MS. I believe that the boundaries are based on both previous mtDNA studies (early 2000’s, which had some more extensive sampling) and presumed habitat preferences (consobrinus being the “prairie” lizard, undulatus more often associated with woodlands) and but this is really just a guess/generalization.
The two species aren’t generally IDable based on visual evidence, and it’s likely there’s some gene flow between the species (though I don’t know of any hard evidence here, other than the fact that the MS consobrinus sample in the Leache et al 2009 paper clusters with undulatus in some analyses). Sounds like a good masters project for someone local!
Anyways, I probably wouldn’t worry too much about the iNat IDs in the area as long as they are to the genus level. Once someone does a more definitive study they can be corrected on iNat. The Leache map and Peterson guide are a reasonable approach for the time being, I think.

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In my state (New Mexico), Sceloporus undulatus used to be the common lizard everywhere, documented from every county. Of course, now we have 3 species (none of them undulatus) and in many places we just have to say it’s a Sceloporus sp. because they’re indistinguishable externally. I find these genomic studies with taxonomic implications frustrating as they seem to rarely clarify nomenclature. Yes, there indeed may be multiple species, formerly obscured under the name S. undulatus, but if the researcher is using specimens from a rather small number of scattered locations and they don’t have a handle on contact zones and extent of hybridization and introgression, the conclusions are, in my mind, suspect.

(Incidentally, S. consobrinus might not even be the proper oldest name for that species … might be S. thayerii. Just to add to the confusion.)

That’s my gripe for the day.

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For anyone interested, the original article that split up S. undulatus is available online at https://academic.oup.com/sysbio/article/51/1/44/1631347. It only sampled around 50 specimens from across the entire former range of undulatus, so its borders are very fuzzy. I wasn’t aware of the 2009 paper, thanks for posting that.

For unidentified or already genus-level observations of former S. undulatus complex species I generally ID the lizards in questionable areas at just the genus level then use the “This ID is as good as can be” checkbox at the bottom to get it out of the Needs ID category. At the same time though I’m generally not going to disagree with an observation someone’s already added a species-level ID on since it’s not technically wrong, per se.

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It’s not the genomic studies or their findings that are frustrating, it’s mother nature that’s frustrating us–as she doesn’t always provide nice, tidy categories (taxa) to satisfy our innate human desire for them. Don’t blame the studies for simply revealing mother nature’s messiness. :)

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I wasn’t. But too many of these studies are based on too few sample locations. We don’t really know what’s going on in those big gaps between sample sites. No such study can cover all parts of a geographic range but better resolution than what we often see would be nice.

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Oh, absolutely. I understand what you mean now. Very true! It’s so hard to get samples over such large distances–not enough time or money.