Debit card--why listed by PayPal as credit card?

[rucalex]

I recently added a debit card when I opened an account with a

credit union. The card plainly says on its face that it is a debit

card (though of course it also says Mastercard). Why does PayPal

list it as a credit card when it listed another card linked to my

bank account as a debit card (which it in fact is)?