Gubernaculum (nematode anatomy)

In nematodes, the gubernaculum is a hardened or sclerotized structure in the wall that guides the protrusion of the spicule during copulation.

[1] For example, in Caenorhabditis elegans, spicules serve to open and dilate the vagina of the hermaphrodite and the gubernaculum is a grooved plate in which the spicules move; the gubernaculum is controlled by two erector and two protractor muscles.

[1] The shape and size of the gubernaculum are often important characters for the systematics of nematodes.

[2] This nematode- (or roundworm-) related article is a stub.

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Posterior end of a male nematode, Gongylonema pulchrum , showing right spicule and gubernaculum
Drawings of a male philometrid nematode - E and F represent the gubernaculum