Lacking spores or having no spores; unable to produce or contain spores for reproduction.
From Greek 'a-' (without) + 'spora' (spore) + '-ous' (adjective suffix). The '-ous' suffix creates adjectives meaning 'full of' or in this case, 'lacking' when combined with the privative 'a-' prefix.
An 'asporous' fungus or fern is basically a biological dead-end—without spores to disperse, it can't spread to new locations, which is why many asporous organisms are restricted to very specific habitats.
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