Thanks, Byron! Great info.
So, in other words, for a fish to be named, someone has to look at its external characteristics, dissect it, test its DNA, and then get a paper published....where? In an icthyological journal? Or does the ICZN have its own publications? If a fish is undescribed, it means no one has got around to doing that? With all the undescribed species of loricariids and corydoras, this looks like shooting fish in a barrel (sorry) for PhD students desperate for publications. It seems surprising that so many fish which are known in the aquarium trade remain undescribed. If one wanted to describe CW045, one could find them easy enough.
You're welcome.
There are many scientific periodicals/journals that publish scientific papers on many aspects of science. There are hundreds I presume. If you do a search using Google Scholar and enter "corydoras" as the search, you will have 6,400 entries for scientific papers on some aspect of Corydoras. Obviously not all are dealing with taxonomy, but many do. And there is a link to the Abstract (where this is available online) and a link to the entire paper (many are free, some require registration).
Another source is the California Academy of Sciences, Eschmeyer's Catalog of Fishes. This is a listing of every described species of fish on the planet, and each entry begins with the first description and then provides every subsequent reference in agreement or not up to the present. There are often links to each scientific paper, especially the newer ones which are not well known. The list also gives every name the species has had.
As an example, here is the entry for Corydoras splendens, the former Brochis species I mentioned previously that has changed; you can search from any of the scientific names, and at the end of the entry the currently accepted name is given. The site of the holotype (the fish used to initially describe the species) is alos included. This catalogue is a mine of information. All of the listed documents which have a number link will take you to that document in the CAS database, and there is a link in that entry to the online document if one exists.
splendens, Callichthys Castelnau [F. L.] 1855:39, Pl. 18 (fig. 3) [Animaux nouveaux or rares v. 2; ref. 766] Rio Tocantins, Brazil. Holotype (unique): MNHN 0000-4291. Type catalog: Bertin & Estève 1950:65 [ref. 19575], Ferraris 2007:125 [ref. 29155]. •Valid as Brochis splendens (Castelnau 1855) -- (Nijssen & Isbrücker 1970:157 [ref. 22239], Ortega & Vari 1986:16 [ref. 9708], Burgess 1989:364 [ref. 12860], Britski et al. 1999:127 [ref. 24147], Isbrücker 2001:218 [ref. 26805], Reis in Reis et al. 2003:293 [ref. 27061], Barriga S. 2012:111 [ref. 35745]). •Valid as Corydoras splendens (Castelnau 1855) -- (Ferraris 2007:125 [ref. 29155], Tencatt et al. 2013:258 [ref. 32752], Barriga S. 2014:111 [ref. 35745], Sarmiento et al. 2014:190 [ref. 35004], Tencatt et al. 2014:78 [ref. 33230], Tencatt & Pavanelli 2015:294 [ref. 35434], Tencatt & Evers 2016:[12] [ref. 34387], Tencatt & Ohara 2016:[13] [ref. 34353], Tencatt et al. 2016:[18] [ref. 34388], DoNascimiento et al. 2017:73 [ref. 35633]). Current status: Valid as Corydoras splendens (Castelnau 1855). Callichthyidae: Corydoradinae. Distribution: Amazon River basin: Brazil, Bolivia, Colombia, Ecuador and Peru. Habitat: freshwater.
It has been conjectured that among all life there are more species we have not even discovered let alone described than there are described species, and as we are today witnessing the greatest rate of species extinction (aside from the catastrophes like meteorite decimation of the dinosaurs) many will disappear before we even know they exist.