Flag for Taxon: North American Spur-throated Grasshoppers (Genus Melanoplus)
| Flagger | Content Author | Content | Reason | Flag Created | Resolved by | Resolution |
|---|---|---|---|---|---|---|
| birdwhisperer | North American Spur-throated Grasshoppers (Genus Melanoplus) |
Requesting the potential of creating "species groups" for these taxa to identify a observation to a couple of closely related species instead of the whole 200+ species genus. I believe "subgenus" is the equivalent to this. |
Jul. 29, 2020 23:31:21 +0000 | birdwhisperer |
Complexes implemented to accommodate species groups. |
Comments
A subgenus is a monophyletic clade of taxa, so it is different. But it does sound like something is needed to clean up Melanoplus.
To answer @kitty12 question, the Orthoptera Species Files breaks the genus into many closely related groups based on body structure and male genitalia. Example being:
species group sanguinipes
Melanoplus sanguinipes
Melanoplus femurrubrum
Melanoplus borealis
Very short list, this group has 11 species but they can be identified by their long wings, subgenital plate only covering the bottom half of the abdomen tip and the superanal plate is very underdeveloped. Species from this group are also tend to be found across North America. On the other hand we have:
species group immunis
Melanoplus immunis
Melanoplus lovetti
Melanoplus rehni
This species group has 7 species. They can identified by their short, flightless wings, complex cerci and restricted range to the Wilmette Valley and Coastal Range of Oregon and northwestern California.
I don't know how much DNA work has been done but I would think with such physical distinctions, Melanoplus is one of many genera but most of these species groups are easily identifiable.
Thank you!
@brandonwoo @alice_abela @jimmylegs @tkoffel
Once again tagging Orthopteran experts/top identifiers for an overall opinion of the above issue. To understand the issue better, a "species group" is an informal name for a group of very similar species, usually from a very large genera (+200 species usually), with the scientific name usually being the nominate species of the group. Example: sanguinipes group. This term has been used by authors for at least the last 100 years to avoid the formal naming of subgenera or sections (botany). OSF, the current external taxonomic source for Orthoptera on iNat, follows Daniel Otte's placement of many Melanoplus species into these groups. The reason this placement is important because in most cases, you can't identify to species but you can easily identify them to species group which would put the observation at a much more refined placement.
Because of the terminology across various groups of organisms, it was brought up in the forum to add species groups to iNat's taxonomic ranking. Concerns are bogging iNat's database, erroneous identifications to species or group level, and formatting the rank name to appear after scientific name (e.g. Tribe Melanoplini and Group sanguinipies vs sanguinipies Group). Overall, the implication of species groups does not seem to be in the near future of iNat, however alternatives have been provided, so I figured we'd vote on the options.
1) status quo -- no changes to the current Melanoplus taxonomy (or Orthoptera taxonomy for that matter in terms of species groups)
2) complexes -- it has been suggested that complexes = species groups and since complexes are too an informal taxonomic rank, there's no rules inbounding how a complex can be named. Example: https://www.inaturalist.org/taxa/1101426-Condylostylus-caudatus-group
3) convincing reason to add species groups to iNat taxonomy
@birdwhisperer as I've said here on iNat before, I have no taxonomic expertise in Melanoplus sp. but enjoy helping with the easily IDable species (mostly M. differentialis, M. bivitattus, M. punctulatus and M. thomasi). That being said, I've always wished we had species complexes within Melanoplus sp for the exact reasons you are bringing up. So I am completely in favor of your suggestion and vote 2) (or 3, the difference being a little subtle for me). If this were to happen, I would start IDing all the Melanoplus sanguinipes complex instead of skipping them.
By the way, are there other potentially interesting monophyletic species complex out there? What about Melanoplus packardii/Melanoplus foedus? Or some short-winged species in the Eastern US?
In general, I'd be in favor of incorporating groups, but I'm not sure that it would add a lot of clarity for California Melanoplus in particular. Having an informal group, like unidentified Melanoplus nymph, would be more useful for sorting since they could be easily separated from adults which may be identifiable at some point. I think the nymphs may be sortable by indication of lifestage, but I just don't have time to do this for all the observations I review.
I would think though, if we can get all adults into their respective groups, there's no need to make a taxon purely for nymphs as we can leave them all at genus level.
I'm still looking for feedback before we do or do not add implement species groups in the form of complexes. Please feel free to tag any Orthoptera experts I didn't mention above. @kitty12 You suggested it in the first place, do you approve incorporating complexes to simplify identification of this genus? And use that taxon rank as an alternative for all OSF "species groups"?
I don't really have any expertise in the area to contribute - I was hoping to learn something, and I did!
If implementing species complexes in lieu of species groups helps people to learn, I think I could support it. I wouldn't get too hung up on what it's called, but I am sure there are lots of people who would, so I do think we need to consider the potential for lots of future flags from taxonomy purists.
@bouteloua I'm transferring our previous discussion over to here about the complex clarifications. As you'll read above, I've been thinking about creating complexes as an equivalent for "species groups" listed on OSF. This I believe will remarkable help identifiers since most Melanoplus grasshoppers (nymphs excluded) can be field identified to species groups regardless if male or female. Admittingly though, if I had created them beforehand, I would've added the suffix "group": ex. Complex sanguinipes group. It sounds like, with the clarifications, that such suffixes are discouraged and the complex should be Complex Melanoplus sanguinipes instead. Do I have that correct?
"species complex", "species group", "aggregate species", "super species", "species swam", "sibling species", "cryptic species" all currently fall under rank=complex on iNaturalist. These are all informal groupings (in the sense of the taxonomic codes to my understanding). It's unlikely staff will ever add additional ranks if rank=complex already achieves what we're trying to do by including such a taxon on iNat in the first place, i.e. creating a useful rank for people to identify that isn't genus or species.
I can't speak as to whether these species groups meet the "utility" clause in the Curator Guide since I don't know anything about these grasshoppers, but to answer your question, yep, it'd be simply "Melanoplus sanguinipes" entered where it says "Scientific name". Then select rank=complex, and you can assign an English common name like "Migratory Grasshopper species group" or something. Ideally the staff would hard code something that makes distinguishing between the species taxon and the complex taxon a bit more obvious.
For those still following the topic, I also want to forewarn that there are some discrepancies between OSF and BugGuide (only discussed on the Melanoplus page, not implemented into their taxonomy) in regards to species groups. I pulled up the complete list of these disagreements and this is a summary:
BugGuide has the bowditchi group that contains 6 species; none of these species are in a group on OSF.
BugGuide has the sanguinipes group as femurrubrum group since the latter is the "type" species. Also includes more species.
BugGuide has packardii group as angustipennis group with also includes more species than OSF.
BugGuide has bivittatus group obtaining members of the ponderosus and punctulatus groups.
BugGuide has the nigrescens group which contains most members of the texanus and immunis groups.
BugGuide's occidentalis group has members from both texanus and keiferi groups.
BugGuide has unspecified aplinus and infantilis together as a group.
BugGuide has a lankinus group that contains unspecificed and rileyanus species.
BugGuide and OSF match all members of the virdipes except species gracilis.
For those still following this topic, due to the lack of disagreements with implementing these taxa and the generally agreement for identification reasons, I've added all "species groups" in the form of complexes, with all species being assigned to their respective group. That means the complexes and the species within them match OSF to the tee. Species gracilis, harperi, mexicanus remain directly linked to the genus due to being in a monotypic group. I will also start creating atlases to go with these complexes to help observers see what's expected to be in their area. If there are still some that don't really think complexes to represent species groups are a bad idea, here's my reasoning to do this.
There are 365 species of Melanoplus, 54 of which are long-winged species, 311 flightless, short-winged species. By body structure, coloration and range, all of these species can be identified to a unique clade of morphologically similar species. As in the case with the sanguinipes group, they are widespread long-winged species, generally of small size. M. sanguinipes and M. femurrubrum can be identified to species if a male is present, but females can only be identified accurately as "M. sanguinipes group". As another example, members of the montanus group can only be identified by the dissection of male genitalia and viewing the internal organs. Even though by range, yours is probably M. montanus but it would be more accurate to call it by the species group.
As a final note before I close this flag, there are 94 species on OSF that are not assigned to species group. I have looked into this subject and looking at OSF provided photos and other sources, I believe we can lower that number by 40 species if a peer review paper was published and accepted by OSF. My notes, if I were to be the person to do this, it would eliminate the monotypic groups and introduce the additions of 5 new groups, several of which David Ferguson has been saying for years on BugGuide. Hope this helps with anyone with questions.
@birdwhisperer thank you for spearheading this, I am looking forward to using these!
Isn't this "species complex" groupings?