The taxa are described in taxonomic treatments, well defined sections of scientific publications (Catapano 2019). They include a nomenclatural section and one or more sections including descriptions, material citations referring to studied specimens, or notes ecology and behavior. In case the treatment does not describe a new discovered taxon, previous treatments are cited in the form of treatment citations. This citation can refer to a previous treatment and add additional data, or it can be a statement synonymizing the taxon with another taxon. This allows building a citation network, and ultimately is a constituent part of the catalogue of life. - Taxonomic Treatments as Open FAIR Digital Objects https://doi.org/10.3897/rio.8.e93709
"Traditional" academic citation is from article to article. For example, consider these two papers:
Li Y, Li S, Lin Y (2021) Taxonomic study on fourteen symphytognathid species from Asia (Araneae, Symphytognathidae). ZooKeys 1072: 1-47. https://doi.org/10.3897/zookeys.1072.67935
Miller J, Griswold C, Yin C (2009) The symphytognathoid spiders of the Gaoligongshan, Yunnan, China (Araneae: Araneoidea): Systematics and diversity of micro-orbweavers. ZooKeys 11: 9-195. https://doi.org/10.3897/zookeys.11.160
Li et al. 2021 cites Miller et al. 2009 (although Pensoft seems to have broken the citation such that it does appear correctly either on their web page or in CrossRef).
So, we have this link: [article]10.3897/zookeys.1072.67935 --cites--> [article]10.3897/zookeys.11.160. One article cites another.
In their 2021 paper Li et al. discuss Patu jidanweishi Miller, Griswold & Yin, 2009:
There is a treatment for the original description of Patu jidanweishi at https://doi.org/10.5281/zenodo.3792232, which was created by Plazi with a time stamp "2020-05-06T04:59:53.278684+00:00". The original publication date was 2009, the treatments are being added retrospectively.
In an ideal world my expectation would be that Li et al. 2021 would have cited the treatment, instead of just providing the text string "Patu jidanweishi Miller, Griswold & Yin, 2009: 64, figs 65A–E, 66A, B, 67A–D, 68A–F, 69A–F, 70A–F and 71A–F (♂♀)." Isn't the expectation under the treatment model that we would have seen this relationship:
[article]10.3897/zookeys.1072.67935 --cites--> [treatment]https://doi.org/10.5281/zenodo.3792232
Furthermore, if it is the case that "[i]n case the treatment does not describe a new discovered taxon, previous treatments are cited in the form of treatment citations" then we should also see a citation between treatments, in other words Li et al.'s 2021 treatment of Patu jidanweishi (which doesn't seem to have a DOI but is available on Plazi' web site as https://tb.plazi.org/GgServer/html/1CD9FEC313A35240938EC58ABB858E74) should also cite the original treatment? It doesn't - but it does cite the Miller et al. paper.
So in this example we don't see articles citing treatments, nor do we see treatments citing treatments. Playing Devil's advocate, why then do we have treatments? Does't the lack of citations suggest that - despite some taxonomists saying this is the unit that matters - they actually don't. If we pay attention to what people do rather than what they say they do, they cite articles.
Now, there are all sorts of reasons why we don't see [article] -> [treatment] citations, or [treatment] -> [treatment] citations. Treatments are being added after the fact by Plazi, not by the authors of the original work. And in many cases the treatments that could be cited haven't appeared until after that potentially citing work was published. In the example above the Miller et al. paper dates from 2009, but the treatment extracted only went online in 2020. And while there is a long standing culture of citing publications (ideally using DOIs) there isn't an equivalent culture of citing treatments (beyond the simple text strings).
Obviously this is but one example. I'd need to do some exploration of the citation graph to get a better sense of citations patterns, perhaps using CrossRef's event data. But my sense is that taxonomists don't cite treatments.
I'm guessing Plazi would respond by saying treatments are cited, for example (indirectly) in GBIF downloads. This is true, although arguably people aren't citing the treatment, they're citing specimen data in those treatments, and that specimen data could be extracted at the level of articles rather than treatments. In other words, it's not the treatments themselves that people are citing.
To be clear, I think there is value in being able to identify those "well defined sections" of a publication that deal with a given taxon (i.e., treatments), but it's not clear to me that these are actually the citable units people might hope them to be. Likewise, journals such as ZooKeys have DOIs for individual figures. Does anyone actually cite those?
