Thoughts on specifying organism forms? (Harmonia axyridis)

I’m not a professional, I’m just an amateur who thinks iNaturalist is neat, and in doing this I’ve found myself getting really interested in beetles–specifically lady beetles.

I learned that there are different forms of the Asian Ladybeetle (Harmonia axyridis) and thought that was really interesting. I see that iNat has four named forms for this species, and I also noticed that there were barely any observations for them (probably because not many people know about it). I was curious so I started looking through H. axyridis observations and seeing if any of them fit into one of the four forms (there’s so much variety within that species) and suggesting that as an ID. I thought it would be really neat to see it get as specific as possible because that could help if people wanted to do research on specific forms or just were curious. I personally am interested to see any patterns in habitat and have already noticed a few trends!

I am a big nerd for comprehensive and consistent data, so I figure hey, might as well make it the most specific it can get, even if it just for fun. I was curious if other people had thoughts about this.

Would this mess anything up? I know that those form observations are no longer shown on the map of the regular Harmonia axyridis observations on the taxonomy page. (However there are hundreds of thousands of observations for the species level, so it is not a noticable difference considering there are so few form IDs.

Again, I’m just someone who enjoys surfing iNat and learning, and thought this was neat, but was curious if other people had thoughts.

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For what I’m familiar with (mollusks/shells), form essentially means variant within a population. This is not indicative of evolutionary relationships, and is therefore not used taxonomically anymore. But I’m pretty sure it’s different for plants, and I don’t know about insects. So I’m not even sure those taxa should exist in iNat. But as they do, you can certainly use them for IDs.

I’m not sure why this would be the case. Are you sure about that? I know there are similar threads about subspecies IDs, which can get weird.

There was a huge effort by the UK Ladybird Recording Scheme around 2008 to record the forms of Harmonia axyridis. Usually they will be described taxonomically as H. axyridis f(orma). spectabilis, some, generally older, literature will also use ab. for known aberrant forms). You can see some of the literature they put together at this time here, including a useful sheet of the common forms.

Recording forms is common for moth species: a common UK moth, the Riband Wave, for instance. In some cases highlighting that there are different forms can help other iNaturalist observers.

There can be significant scientific interest in forms where a given population is polymorphic (melanism in the Peppered Moth is the classic example). Other examples include: the common Cepea species of snails, chromosome polymorphism in mice (historically some were given full taxonomic names, such as Mus poschiavinus, the tobacco mouse). Different colour forms may experience different selective pressures even though the difference may be in a single gene.

Lastly there are observation fields: “Form”, “Ladybird Form” and “Form Name”. These look to be meant for capturing this kind of detail, and by the looks of things Ladybird Form refers to Harmonia axyridis, but doesn’t seem to be used. Here’s an example of an observation using “Form”.

If I’m understanding you correctly, I imagine that this could be done through the observation field, if one exist or could be made.

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This observation https://www.inaturalist.org/observations/171612036 which has been IDed as a form appears on both the map page for the form (https://www.inaturalist.org/taxa/1470510-Harmonia-axyridis-axyridis) and for H. axyridis (https://www.inaturalist.org/taxa/48484-Harmonia-axyridis). So I don’t think that IDing as a form should be a problem for mapping at least.

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Just because a form is well known or of scientific interest does not make it a taxon. I think sticking to observation fields makes the most sense for those cases.

I’m sure some dedicated splitter will find a way to make it into a new species.

Not if the form is found sprinkled across different unrelated populations. In my fields, that’s the definition of a form.

I do not think it is limited to that one species of Lady Beetle.

Six-Spotted ZigZag Lady Beetle (Cheilomenes sexmaculata) has a few forms as well. Here is the taxon page which confused me for a long time because as you can see the ones I observe in my garden are of a different form. (Like you, I am also not a professional.)

I have often wondered where the geographic distributions are. Like others, I agree the observation fields would likely work well for that. I believe there is even a mapping function somewhere?

Same as above goes for Ashy Gray Lady Beetle (Olla v-nigrum) where the form I see is considered the additional form.

@thomaseverest : I don’t think I said that. I’m certainly aware they fall outside the Zoological Code (but not the Botanical Code). Many are just point mutations in single genes, as some of my examples implied.

My final recommendation was to use observation fields, not set up taxa.

There is no agreed-upon number of base pairs to define a species-level difference.

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