Translation:I have no wallet, watch or keys.
I agree, the fact that the (português) sentence is missing an article is confusing. In the English translation, the 'no' acts as the article: "I have no wallet, watch, or keys." In German, the translation would be: "Ich habe keine Brieftasche, Armbanduhr, oder Schlüssel." In this translation, the 'keine' is the (negative) article.
when I say informally, I mean in any situation, even in an important meeting. Sometimes when writing, people prefer using other types. But this sentence can be translated in many ways. If you want to enhance/highglight each object, you can use "nem" before each of them. "Eu não tenho nem carteira, nem relógio, nem chaves..."