Predatory behavior of Cupelopagis vorax (Rotifera; Collothecacea; Atrochidae) on protozoan prey

摘要: By rotating on a short, flexible, pedal stalk, Cupelopagis vorax captures prey that traverse the substratum to which this sessile rotifer attaches. Microvideographic analysis (including slow motion and freeze-frame) permitted us examine some of details foraging behavior. When undisturbed, usually faces forward in resting or neutral position (NP) with its unciliated infundibulum (corona) directed parallel surface substratum. However, vibrations produced by artificial means (fine pins) small (protists) evoke unique behaviors Cupelopagis. Our two protozoan (Paramecium bursaria small, unidentified flagellate, SUF) indicates predator possesses 360 ° encounter field (EF) biased towards NP Size EF appears be function both size, but it extends at least 650 µm, as measured from point attachment predator's stalk comes close Cupelopagis, can lean toward organism, stretching extending corona over swift (< 0.5 s). Probability capture after attack was type (61.6% for P. 41.5% SUF). Analysis has handling time ranging few seconds several minutes: 24.6 ± 16.8 s (n= 274) 34.6 25.4 SUF (n=111). Occasionally sweeps part retracting corona, turning right left (mean angle subtended ≈ 63 42 °), unfolding slowly returning original position. This behavior, termed surveillance, occurs presence absence prey. While not ability detect water movements, is only known exhibit specific potential