Spicule (nematode)

In nematodes (roundworms), spicules, or copulatory spicules, are needle-like mating structures found only in males.

Males nematodes may have one or two spicules, which serve to open the vulva of females, and facilitate the transmission of sperm, although sperm is not transferred directly by or through the spicules. The gubernaculum is another organ of the nematode male copulatory system, which guides the spicules during copulation.

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