During the hot summer months, the noisy cicada creates a musical chorus among a group of forest trees. You may see them clinging to the side of a tree. When they do this they are sipping a tasty natural tree fluid called “xylem”.
Xylem contains amino acids and minerals. It is almost like a natural protein shake. Cicadas lack mouth parts and instead use their straw-like proboscis, the rostrum, to suck up the tasty xylem. The rostrum can be used to pierce rootlets, roots, and branches.
Ouch! Luckily the rostrum isn’t sharp enough to pierce skin!
The rostrum is retractable-it can be hidden underneath the cicada’s body like a straw on top of a children’s juice cup. It has three parts: the clypeus (the “face” of an arthropod), labrum (or anteclypeus), and labium. The labium is like a straw and has the stylet inside of it, which is comprised of the mandibles and maxillae. This labium is sharp enough to allow the cicada to pierce food sources. The labrum is the part of the beak that connects the labium to the rostrum. The clypeus looks like the nose of the cicada. It contains enormous pumping muscles in order to suck the xylem up.
The rostrum looks like a retractable straw under the cicada’s body
The clypeus uses pumping muscles to such up xylem
Cicadas are not impolite when it comes to taking drinks from trees. They will put the cork back into the bottle, so the speak. The cicada have polymerized, viscous saliva that will plug up the holes that their mouth parts create in tree bark. This ensures that xylem does not leak from the food source.
Young cicada nymphs are smaller than a grain of rice when they first begin to feed. They like the tiny roots of grasses since they are just the right size. The nymphs also prefer the grass rootlets to deciduous tree roots since they are available all year.