The Corydoradinae catfish are currently (2021) divided up in to 9 Lineages based on morphometric data (i.e. depth of body, head length, snout length etc.).
You can read my arcticle about this here: Corydoradinae Lineages
The Author(s) is the person(s) that scientifically described the species.
An attempt at grouping similar looking species for easier ID.
The name given is for either the most common species in the trade or the first described species in the ID group.
Valid subspecies for this species.
Synonyms (mainly no longer valid names), but also Trade Names for this species.
What the scientific name means or is derived from.
The place where the type specimen (the one used for the scientific description) was collected.
Which River or Drainage system does it come from.
The species names in different languages.
How to tell the difference between boys and girls. Crucial if you want to breed them, otherwise it usually makes very little difference.
The length from the tip of the mouth to the beginning of the tail at the caudal peduncle. (Total length refers to the length including the tail.)
How peacefully it is towards its own species and other Corydoras species.
Corys are generally a schooling fish but some of the species are territorial or VERY territorial.
For Lineage 1 (saddle-nosed) and 3 (Scleromystax) you should keep in a smaller group in a large enough tank, where each male can keep his territory. There need to be space for hideouts for the females and sub-dominant males.
In theses two groups they might kill each other!
This is my attempt a rating how hard a species is to spawn or not. It can vary a lot depending on what type of water you have access to, how much you are willing to change parameters etc.
A long time ago I wrote an article about how to simulate dry and rainy seasons in the tank that might help you spawn some of the more difficult species: Dry and rainy season in the tank