Question

In the parasitic barnacle order Rhizocephala, the larvae metamorphose into a _______ _______ that injects cells into the hemocoel of the crab that grows into root-like processes throughout the crab body.

a. Sacculina larva
b. Nauplius larva
c. Cypris larva
d. Zoea larva

Answer 1

The larvae of Rhizocephala barnacles metamorphose into a cypris larva, which then injects cells into a crab to grow and parasitize.

Step-by-step explanation:

In the parasitic barnacle order Rhizocephala, the larvae metamorphose into a cypris larva that injects cells into the hemocoel of the crab that grows into root-like processes throughout the crab body. The correct answer is c. Cypris larva.

The cypris stage is significant for barnacles as it is their seeking, mobile phase, during which they must find a host. Once the cypris larva locates a suitable host, such as a crab, it attaches and injects its cells into the host, eventually developing into a sedentary, parasitic adult form. This fascinating life cycle is a clear example of complex parasitism in marine crustaceans.