Can anyone tell me

The color difference, or if there is any difference between the T. cupreus and the T. plumipes? Those are the two that look the most similar/the same to me. Have a hard time telling them apart. I know the common names are different, but to me the T. cupreus looks a lot like the plumipes. I'm thinking of getting a Tap of somesort (my top seems to be rare/hard to find at the moment, and so I'm just looking at all the other ones, getting to know the differences etc).