How to trace authority flow for taxon changes

I’m trying to figure out what the flow of data is around taxon changes, from publication of the source paper to eventual updating of iNat’s taxon records and any ancillary split/merge work.

To simplify the discussion, my enquiry is spurred by the reclassification of Dichelostemma capitatum as the resurrected species Dipterostemon capitatus, for which strong evidence was presented in this 2017 paper:

Preston, R.E. 2017. New nomenclatural combinations for blue dicks (Dipterostemon capitatus; Asparagaceae: Brodiaeoideae). Phytoneuron 2017-15: 1–11.

Let’s work at this from the iNat end of the chain. My understanding is that iNat treats Kew’s Plants of the World Online (POWO) as its authoritative source for plant taxa. But I only know that because I’ve read that in comments by other curators.

Q1: Is there a page that documents the authorities that iNat uses for each part of the taxonomy?

My understanding is that there are no automated processes in place to update iNat based on changes to these authorities, although iNat staff can stage bulk updates. I do understand why that’s necessary, as there currently needs to be a manual review of possible downstream effects.

Q2: Is there a page that documents the overall process of updating one or mutliple taxa based on changes by an authority?

Moving out of iNat and into the wider taxonomic world, POWO currently sees Dipterostemon capitatus as a deprecated synonym for Dichelostemma capitatum, based on a 2000 assessment of the original 1912 species definition.

Q3: Am I right to think that until POWO gets updated to reflect Preston’s 2017 paper it isn’t appropriate to change the iNat record for Dichelostemma capitatum?

My understanding is that POWO itself uses a taxonomy maintained by Kew in the World Checklist of Selected Plant Species (WCSP). For this taxon, the sources that WCSP and POWO cite are the World Checklist of Seed Plants (2000) and Flora of North America (2002). I read some of the WCSP FAQ, but it’s not clear to me what the schedule or trigger would be to update WCSP’s taxonomy. There seems to be a fundamental disconnect between the increasing volume of taxonomic change driven by genomics and the traditional editorial process.

Tracing sources back further takes me to the online Flora of North America, which has a nice treatment written by J. Chris Pires. This mentions work from 1996 and 2000 that hints at the forthcoming separation of Dichelostemma capitatum into its own genus, but leaves it unchanged (after all no botanist had yet formally severed the taxon from Dichelostemma).

And then there’s California’s own Jepson Flora Project, which on 10 December 2019 published updates deprecating Dichelostemma capitatum and accepting the resurrected Dipterostemon capitatus, based on correspondence received.

Obviously the work involved to update taxonomies at global or national scales moves more slowly than at a local scale. But it would be nice to see a shorter delay between published research and an iNat taxon update than is implied by WCSP’s reliance on a 2002 source.

Q4: Is there anything that iNat curators (especially those not in academia) might reasonably do to facilitate this flow of information?

Thanks for your thoughts on any of these points.

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To answer question 1, go to and search for External Taxonomic Authority List. There’s a list of authorities for different taxa there.


That’s very helpful. Not sure how I overlooked that. I think that also answers my Q3. I’d be very interested to hear views on Q4.

Now that I want it I can’t find it, but there was an entire forum thread the other day discussing your Q4

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