Content Author Object Flagger Flag Created Reason Resolved by Resolution
Genus Narceus upupa-epops Sat, 11 Nov 2017 15:39:46 +0000

different taxonomy is being used inconsistently in research grade observations.

loarie

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Hi, I was just looking through the millipede observations in Ontario and noticed that there were "giant" millipede observation labelled both Narceus americanus and N. annularis, and both being accepted as Research Grade. This seems to be the case throughout the northeast; e.g. Pennsylvania and NY. I did a bit of research, and it looks like the 2 species can't be separated from photos and might be the same species. They're generally classified as Narceus americanus/annularis complex, which used to be an available taxon on iNat but isn't right now.
If the species are combined, then my understanding is that all of them would be N. americanus. If they're kept separate, N. annularis would be the species in the northern part of the range.
It seems like these options are being applied inconsistently in iNat.
https://bugguide.net/node/view/15012
http://eol.org/pages/310313/details
http://inaturalist.ca/observations/6769713

Posted by upupa-epops over 2 years ago (Flag)
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I agree that Narceus a/a is a mess. If what we are after is the truth (see i.e. Plestiodons), then marking all as genus Narceus is the best we can do, because there just is no field ID method available. We can't arbitrarily declare a Mason-Dixon line either, because I'm certain the Narceus (if they are different) are intergraded over a many-states wide swath.

Posted by lincolndurey over 2 years ago (Flag)
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Millibase considers both N. annularis and N. americanus as separate valid species http://www.millibase.org/aphia.php?p=taxdetails&id=947026 http://www.millibase.org/aphia.php?p=taxdetails&id=947023

Are you guys saying that they're possibly separate species but that the two species are indistinguishable morphologically? Kind of like Gray and Cope's Gray treefrog?

Posted by loarie over 1 year ago (Flag)
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My understanding was that they had ambiguous or undecided taxonomy that was kind of at a stage where nobody knows if they're one species or two, but officially they're still two because no one's done the work to see for sure yet.
I think the EOL website had the best summary of the situation, but now the website has changed and I can't find that description any more.
But either way, I think they are also indestinguishable if it is two species, although I wouldn't be the best to ask.

There was also this discussion: https://www.inaturalist.org/observations/8993064

Posted by upupa-epops over 1 year ago (Flag)
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Would it be appropriate to restore the species complex "taxon" for this case now that the rules have changes? https://www.inaturalist.org/pages/curator+guide#complexes
https://forum.inaturalist.org/t/how-are-species-complexes-treated/404
I'm not familiar enough with these species to know if there's literature on the complex, but I know the complex used to be an ID option. I could try to find some literature if necessary.

Posted by upupa-epops over 1 year ago (Flag)
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@berkshirenaturalist @latimeria @arborsphere
you guys probably know the most. What documentation can you find to back up resurrection of the Narceus A/A Complex ?
I think bugguide still says they can not be field separated.

Posted by lincolndurey over 1 year ago (Flag)
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As it stands, Narceus americanus/annularis likely encompass more than 2 species. Shelley et al 2006 make the case for regarding these two species as a complex, pending a genetic revision (https://www.researchgate.net/publication/232696482_Distribution_of_the_milliped_genus_Narceus_Rafinesque_1820_Spirobolida_Spirobolidae_Occurrences_in_New_England_and_west_of_the_Mississippi_River_a_summary_of_peripheral_localities_and_first_records_fr).

Walker et al 2009 did a study of the genetic structure in the genus, but didn't make any taxonomic changes, so they didn't clarify anything, unfortunately. They do show genetic structure in the genus, supporting Shelley et al's hypothesis, but we don't have a clear understanding of the genus. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2652443/)

N. americanus's type locality is in South Carolina, and N. annularis's is in New York. I'd consider the NY specimens and northeast of there as annularis, and SC as americanus, but who knows in the rest of the range? I'm not sure how inaturalist wants to handle situations like this, but I regard any observations of these critters as just Narceus. There are few millipedes that can be identified to species just from a photo, and the ones that can be identified from a photo are usually restricted in range and have been revised recently, so I'm always wary with any online identifications unless I check them myself with published range maps.

Posted by derhennen over 1 year ago (Flag)
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@lincolndurey - I'm not an expert of these, yet I admittedly seem to be #1 on the leaderboard for annularis. I recall IDing a few observations as a/a complex when we had that option. Did my IDs get defaulted to annularis when the "complex" was removed as a taxon option?

Posted by arborsphere over 1 year ago (Flag)
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I did setup a complex for the two here: https://www.inaturalist.org/taxa/904631

Posted by bobby23 11 months ago (Flag)
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There are currently over 3000 observations identified as N. americanus and almost 400 as N. annularis. Should these all be pushed back to the complex?

Posted by upupa-epops 10 months ago (Flag)
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I'd say yes, all into the complex.

Posted by lincolndurey 10 months ago (Flag)
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Is it possible to automate that or should we organize a group to do it together?

Posted by upupa-epops 10 months ago (Flag)
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Would it be allowed to merge both species into the complex taxon and then recreate them?

Posted by upupa-epops 9 months ago (Flag)
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Yeah, sounds like it would be useful to auto-sort all observations into the complex

Posted by mws 9 months ago (Flag)
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Alright, I've set up the merge: https://www.inaturalist.org/taxon_changes/65946
Does anyone have any objections before it's committed?

Posted by upupa-epops 8 months ago (Flag)
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I'm for going ahead and committing that

Posted by lincolndurey 8 months ago (Flag)
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Alright, done.

Posted by upupa-epops 8 months ago (Flag)
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looks like this is all sorted? Closing

Posted by loarie 7 months ago (Flag)
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Oh yeah, thanks!

Posted by upupa-epops 7 months ago (Flag)

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