Screen views from the Internet show a condition know as elephantiasis of the scrotum, caused by worms clogging lymph passages. The microscopic larvae causing elephantiasis are carried from human to human by a mosquito. Rotifers These tiny multicellular animals often are smaller than their unicellular neighbors. In some species, males are rare or unknown. The diversity of rotifers is stunning, and this video shows many of the different types.
Planktonic rotifers have special adaptations for open water life.
Some, such as Asplanchna , are transparent, minimizing their chances of being seen by small plankton feeding fish. Kellicottia has long spines that help to stabilize the animal. The large colonial bryozoan found in reservoirs and lakes is Pectinatella . Retreating into their jelly mass, Petinatella individuals are able to avoid most hazards. These fresh-water bryozoans produce unique reproductive structures called statoblasts, equipped with grappling hooks that catch in vegetation.