Age of consent is a state by state issue -- just as requirements for marriage, requirements for divorce, what consitutes child abuse (in some states, spankings are still fine), whether or not you can recreationally use marijuana, whether or not GLBT persons can marry, and many other matters. The age of consent in Nevada is 16, with some caveats (mentally diminished or incapacitated, position of authority, etc.). In general terms, whether male or female, at age 16 you can legally say "yes" to a partner who is also at least age 16. Someone from another state is bound by the laws of Nevada while present in Nevada. This issue is just like so many others -- when in doubt, either look it up or refrain from any questionable conduct.
Responses are for general information purposes only, and are based on the extremely limited facts given. A consultation with an attorney experienced in the area of law(s) indicated in the question is highly recommended. Information and advice given here should not be relied upon for any final action or decision, as the information is limited by its nature to the question asked and the fact(s) presented in that question. THIS RESPONSE DOES NOT CREATE AN ATTORNEY/CLIENT RELATIONSHIP, particularly considering that the names of the parties are unknown.
The age of consent in Nevada is 16. That means it is legal as long as the 16 year old consents. There is no Federal standard because this type of law falls under what is typically a police power of the States. Therefore, each state is allowed to legislate what the age of consent should be. Ignorance of the law is never a defense. When you enter a state's boundaries, that state's laws apply to everyone within its boundaries. It is your responsibility to know the laws of that state.