The prospore membrane is a double-membraned structure that extends from the cytoplasmic face of the spindle pole bodies to encompass the spindle pole bodies and the four nuclear lobes that are formed during meiosis. It helps isolate the meiotic nuclei from the cytoplasm during spore formation and serves as a foundation for the formation of the spore walls. An example of this component is found in Schizosaccharomyces pombe.