How should organisms be identified if what inaturalist considers a species is in the literature considered a complex of several, including undescribed, species?
It has come up in an observation of enchenopa binotata. The opinions appear to be that since it is a species complex, it should receive genus level ID. That seems wrong to me. If E. binotata refers to the complex, then any member of this group should get the E. binotata ID. Perhaps the taxonomy should call it a complex rather than a species. But Iāll be the first to admit that I donāt know what Iām doing.
Looking at other such cases that I have noticed, Pantherophis alleghaniensis appears to be explicitly a complex in the inaturalist taxonomy. Narceus seems to require using the genus level ID for the n. annularis/americanus complex.
You will probably find that complexes are usually where there are two or more taxa and specimens will sit somewhere between them. It just means you need to pick which species description it is most like. You have to remember that a species description is based on a single specimen, and often characters are not black and white but cover spectrums, like black Vs grey, and when does grey become blackā¦
If Iām reading it correctly the iNat taxonomy now seems to include the taxon rank of ācomplexā which I hadnāt noticed before. So in your example there are two entries for Pantherophis alleghaniensis. One is Pantherophis alleghaniensis Complex, which includes, as child taxa, all the species in the complex, and that includes Pantherophis alleghaniensis again, but now being used in the strict sense.
Itās an interesting idea, although I imagine it will confuse some people. There is no formally recognised taxonomic rank of āspecies complexā in any of the codes as far as Iām aware. Sure, you will see āspecies complexā used in the literature as a term to qualify a taxon name (and not so different to using āaff.ā or ācf.ā) but it has no formal standing in nomenclature. I know only formal scientific names are allowed in the iNat dictionary (no tag names) which I can understand. But why is this bit of nomenclatural rule-bending so different?
I donāt think we should be identifying observations to species if thereās no safe way to separate them. In cases where there is cryptic species or species that are impossible to separate without dissection (e.g. Many insects, Arion slugs, possibly Northwestern/America Crow on the west coast, etc.) either genus level or a holding bin field or a new ātaxonā would be better.
My understanding is that since this January species complexes are officially allowed (an issue with Narceus is that there used to be a species complex ātaxonā and they were IDād to that, but then it was removed so they were all identified arbitrarily to one of the two species, or to genus, causing a mess).
Iām not sure if thereās a specific definition for a āspecies complexā to avoid an infinite amount being made? Whatās the difference between a subgenus and a species complex and a tricky pair of species?
Holding bin fields are fine as a temporary placeholder but i donāt think we should be using them in the long term. They donāt work with any of the other filters or lists or the range maps. Iād rather just have the complexes when we can. In the past we werenāt able to do so, so iām glad that was changed. A lot of times in large genuses, identifying to genus when you know itās one of two or three species is a waste.
A subgenus contains species that are thought to be descended from a common ancestor. A tricky pair of species can be difficult to distinguish, but arenāt necessarily closely related. A species complex involves hybrids or incompletely separated species. I think all species complexes would technically be part of a subgenus, but a subgenus could include a species complex plus closely related species whose ranges donāt overlap or donāt hybridize for some other reason.
Seeing that complexes are part of the inaturalist taxonomy, and that this is a relatively recent addition, perhaps the best course of action would be to flag the taxon in question for curation. Iām going to try with enchenopa binotata.
Iām guessing a species group is more expansive than a species complex but less than a subgenus. Would they be allowed as taxa on iNaturalist? For example this group on BugGuide: https://bugguide.net/node/view/1004971
Species groups and species complexes are work-around solutions for populations of closely related organisms which have not yet been fully addressed systematically and taxonomically. If an iNat record can be reliably assigned to such a group/complex ā not at species level but better than just slapping a genus-level ID on it ā then I think itās appropriate to create a taxon that is defined as a group or complex. Taxonomy is never really stable and these provisional solutions are sometimes the best we can do for the moment.
Iād like a species complex or species group option for Bombus vosnesenskii and its look-alikes. Thereās a least one named species and itās suspected that there are others that look the same, in the kind of view we get from photos. Some people are using the subgenus Pyrobombus to deal with this, but that subgenus contains too many species for my purpose. Technically, calling them all B. vosnesenskii is wrong. How do we propose or produce a species group like this?
Flag for Curation the appropriate parent or member species, and make the request. Add a comment to the flag with details, including the proposed member species. Also I suggest reading the Curator Guide section on complexes linked above first, just to make sure itās a viable request. For example, polyphyletic complexes (spanning more than one subgenus, at least) would probably not be accepted.