What do anthropologists call community members who guide, advise, and teach the ethnographer during fieldwork?

Key Cultural Consultants

Explanation:

Community members who guide, advise, and teach the ethnographer during fieldwork are called Key Cultural Consultants.

Key informants

Explanation:

A key informant is a skilled person that conducts interview about a particular organization or social program which can be easily understood by members of the community or society that do not know the full repertory of forms, meanings and functions of their culture.