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Related to Infaunal: Epifaunal, Epifauna, faunas


Aquatic animals which live in the bottom sediment of a body of water.



animals dwelling in bottom sediments of seas, rivers, lakes, and ponds. They include many mollusks, echinoderms, segmented and round worms, insect larvae, some fishes, stone borers (some sponges, mollusks, sea urchins), and wood borers (the mollusk Teredo, some crustaceans). Infauna is categorized by the type of sediment in which it dwells: pelophilic (in ooze), psammophilic (in sand), lithophilic (in stones), and argillophilic (in clay). Most species of infauna feed on detritus. Certain forms of infauna carry out daily and seasonal vertical migrations. Infauna is important as a source of food for fishes that feed on bottom-dwelling animals (benthos).

References in periodicals archive ?
Benthic foraminiferal are moderately diverse (around 41 species), with similar proportions of epifaunal and infaunal taxa.
Infaunal survival: alternative functions of shell ornamentation in the Bivalvia (Mollusca).
1999), and MacEachern and Gingras (2007), who suggested that these conditions characterize brackish-water trace fossil assemblages hy: 1) a low diversity; 2) domination by monospecific suites; 3) traces typically present in marine rather than freshwater environments; 4) a trend toward simple burrowing structures formed by opportunistic organisms; (5) sporadically distributed ichnogenera; and 6) infaunal traces predominating over epifaunal ones.
The polychaete worms represent one of the largest infaunal communities found in benthic environments world-wide.
These borings are evidence of the ability of these infaunal worms to bore into the calcareous substrates, but they are presumably not specific to any kind of shells as the substratum.
Photoinduced toxicity of PAHs and alkylated PAHs to a marine infaunal amphiod (Rhepoxynius abronius).
First, we measured the impact of green crab predation on three different functional groups: infaunal invertebrates including suspension-and deposit-feeding molluscs and polychaetes, epifaunal invertebrates including decapod crustaceans, and vertebrate predators including wintering shorebirds.