"Click mechanism model of the furca. The furca, at rest, is retracted into an abdominal ventral groove. A pair of ""basal rods"" (springs) are embedded in ventral and lateral parts of the abdominal sclerites 4 & 5, these springs also attach to the apex of the furca. The spring/click mechanism gets help from muscle and active dorsiflexion of the body, which both help release to spring organ from the groove)"
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