Gastrotrichs: Gastrotricha

Physical characteristics: Lepidodermella squamata (abbreviated as L. squamata) gastrotrichs are shaped like bowling pins and grow to a length of 0.007 inch (190 micrometers). The head is separated from the body by a short neck. The trunk has a forked tail and two sticky tubes. The body covering is made up of scales. Hairlike fibers are present on the sides of the head and in two rows on the belly.

Geographic range: L. squamata gastrotrichs live in the United States, Brazil, Uruguay, Japan, and much of Europe.

Habitat: L. squamata gastrotrichs live on plants in lakes, ponds, swamps, and streams. They also may live between grains of sand.

Diet: L. squamata gastrotrichs eat algae, bacteria, and waste.

Behavior and reproduction: L. squamata gastrotrichs glide slowly and are sensitive to blue light. The life cycle begins with development of eggs without fertilization. Up to four of these eggs are laid. Some Lepidodermella squamata gastrotrichs live on plants in lakes, ponds, swamps, and streams. They also may live between grains of sand. (Illustration by John Megahan. Reproduced by permission.) develop quickly, but the eggs usually develop slowly and can survive drying out and freezing. A few days after hatching, the gastrotrich develops both female and male reproductive organs.

Lepidodermella squamata and people: L. squamata gastrotrichs are sold for use in laboratory studies.

Conservation status: L. squamata gastrotrichs are not considered threatened or endangered. ∎