Short but sharp stem emergence (prickles) are present along the ridged stem of Serjania mexicana (Family Sapindaceae), a tropical liana, which probably uses these as hooks to cling to itself, thus forming a nasty thicket, or to support plants, but likely also benefits by discouraging vertebrates from ripping through this climber. There are many climbers in the genus Serjania and the closely related Paullinia; many lack the stem emergences, but all species also have bifid tendrils that form from axillary buds. When sapindaceous lianas become woody, they possess a type of anomalous secondary structure termed cable design, consisting of several cylinders of wood enclosed within the bark.

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