This is the ultimate species wiki template (in my opinion, anyway) that I have been using for my own species to better understand them and it also helps me in writing my story when I need more information.
You can find all my wikis here: Kathula, Halfhumans, Edglings, Humans, Sorcerers
Each of them follows the below template.
Now, this is a template I created for my own writing, so it might not match your style, but I hope you can take something away from it and use it for your world building.
Write it as if you are explaining it to someone. That will help you organize your thoughts and ideas.
– INSERT SPECIES NAME –
WHAT ARE THEY?
Short explanation of what the species is. How to pronounce the species’ name, a little blurb about the species in general, and something important you think might be worth mentioning.
Example (for my species Kathula): They are an anthro-cat race which perform magic through potion-making using natural ingredients like herbs. They age the same way Humans do. So, a sixteen-year-old Kathula is sixteen. There is no such thing as “cat years”.
Singular: Kathula | Plural: Kathula (NOT Kathulas just like you don’t say Sheeps)
WHAT DO THEY LOOK LIKE?
A picture, if you have one, would be nice.
Also add a little explanation of what they look like. Do they have fur? What color? Do they have horns, pointed ears, scales, anything about their looks would go here. Also, how tall are they? If they wear clothes, what kinds of clothes? What’s their fashion?
WHERE DO THEY LIVE?
Here you will talk about the place they live and what it looks like. If it is outdoors and in nature, what kind of environment? If it is a city, what is the city like? If it is a mixture, what does that look like? Pictures would be nice to add.
What languages they speak or write or both.
This might be unnecessary to some of you. This is where you mention the gender spectrum of your species.
Example (for my species Edglings): Male (Shaao), female (Shaai), genderless (Shaar)
You never know. It might be good to think about because you could potentially end up using it in your story.
This is not immediately intuitive, so let me explain.
Here you would talk about if their names mean things or if they even have individual names.
Example (for my species Kathula): Often names have some meaning in relation to their ancestry or habitat.
Example (for my species Edglings): Not all Edglings have individual names. Only certain Edglings of certain status have individual names which they give to themselves. Having an individual name means two things in Edgling culture…
About types of clans (if you have them) and/or the top to bottom social structure (if there is one) of your species. For example, if you have a caste system, you would talk about that here.
If they have magical powers or not. If not magical, if they have any kind of power (such as political power).
*INSERT A SECTION NAME HERE* or two or three
This section (or sections) is for you to name because there may be some things you’ll want to mention which is only particular to a certain species.
For example, I might give a brief overview of what the different Kathula clans environments are like as well as if Kathula look different depending on their clan. I might also mention clan-specific diets. Or, I might talk about what it means to be a King in Edgling culture and how armies work.
Some other things you might consider depending on your species could be: Religion, political parties, educational ranks (e.g., student, professor), how they view other species, what their values are, etc.