Graptoleberis testudinaria is found associated particularly with vegetation rather than being a bottom dweller (1).
Food and Feeding Behavior
Food is collected by scrapers on the second trunk limb assisted somewhat by the first trunk limb. Feeds on minute particles. It is postulated that bacteria must be an important part of its diet (1).
While attached to a substrate G. testudinaria has a smooth gliding motion similar to the movement of a gastropod. The smooth locomotion is accomplished exclusively by the first trunk limbs, though the antennae may be used to overcome obstacles. When gliding the organism has a very firm attachment to the substrate which is achieved by lowering the pressure within the carapace chamber . The body form of G. testudinaria is not designed for effective swimming and will only swim with reluctance (1).
(1) FRYER, G. 1968. Evolution and adaptive radiation in the Chydoridae (Crustacea: Cladocera): a study in comparative functional morphology and ecology. Philos. Trans. R. Soc. Lond., B, Biol. Sci. 254: 221-382 + 384-385.