Nesagapostemon is an extinct monotypic genus of sweat bee in the Halictidae subfamily Halictinae. At present, it contains the single species Nesagapostemon moronei. The genus name Nesagapostemon is derived from a combination of the Greek nesos, meaning "island", and Agapostemon, a very similar genus of halictids which may be related. The species is named in honor of Ettore Morone of Turin, Italy. The species is known from the holotype, a single 9.9 millimetres (0.39 in) long female currently in the private collection owned by Morone (catalog number MACT-1172), and which was first studied by Dr. Michael S. Engel. Engel published his type description in ZooKeys in 2009.