Considering the feeding of the larvae of South American fish, it has been reported that there is a preference for the consumption of larger-sized zooplankton (Cladocera and copepods) and reduced consumption of
Rotifera and Protozoa in the majority of the species studied (Prieto et al., 2006), which corroborates the behaviour displayed by the juvenile forms of Rhamdia quelen durring in the course of the present study, where a greater consumption of Cladocera was observed.
However, the genera Lecane, Trichocerca (
Rotifera) and Alona (Cladocera) are considered non-planktonic phytophilous organisms.
Among
Rotifera, Bdelloidea was the most abundant taxa in the vegetated area, whereas A.
Effect of three food types on the population growth of Brachionus calyciflorus and Brachionus patulus (
Rotifera: Brachionidae).
The high density of
Rotifera in the fish pond studied has been associated with high density of Cyanobacteria (December).
Rotifera from southeastern Mexico, new records and comments on zoogeography.
The dominance o the
Rotifera in Nigerian aquatic ecosystems ha been documented by several authors (Green 1960, Jeje and Fernando 1986, Egborge and Tawari 1987).
Among
Rotifera predominant genera are Ptygura, Hexarthra and Brachionus.
Laboratory studies on the population dynamics of Anuraeopsis fissa (
Rotifera) in relation to food density.
In relation to relative density, the predominant organism group was
Rotifera (11 out of 20 means; Figure 3); the second was Copepoda (five occurrences).
Key words:
Rotifera, Chlorella, population growth, live-alga, dead-alga.
Muller (
Rotifera) in relation to temperature, salinity and food algae.
Hypophthalmus edentatus Pre-flexion Flexion Post-flexion n=157 n=135 n=56 Food items FO D FO D FO D
Rotifera Brachionus 3.7 -- 9.7 2.9 2 -- calyciflorus Filinia opoliensis -- -- -- -- 2 -- Filinia terminalis 0.9 -- -- -- -- -- Keratella americana -- -- -- -- 2 -- Cladocera -- Bosmina hagmanni 80.1 86.6 95.8 87.1 100 75.5 Ceriodaphnia 30.1 7.4 66.6 8.6 95.9 14.3 cornuta Ceriodaphnia 2.8 -- 22.2 -- 20.4 -- silvestrii Daphnia gessneri -- -- 1.3 -- 4 -- Diaphanosoma -- -- -- -- 2 -- spinulosum Moina minuta 5.6 1.2 11.1 1.4 28.5 2 Unidentified 9.4 4.8 1.3 -- 16.3 8.2 Copepoda Cyclopoida nauplii -- -- -- -- -- -- Calanoida -- -- -- -- -- -- copepodites -- -- Cyclopoida 0.9 -- -- -- 2 -- copepodites Argyrodiaptomus -- -- -- -- 2 -- furcatus Mesocyclops sp.
In total, 61 holoplankton taxa belonging to 7 categories: Protozoa, Cnidaria,
Rotifera, Crustacea (Copepoda, Cladocera, Ostracoda, Amphipoda and Mysidacea), Chaetognatha, Mollusca, Larvacea, and 8 different types of meroplankton were also recorded (Table IV).
From these, 12 taxa were identified, four of Cladocera, three of Copepoda, four of
Rotifera and the larvae of Chaoborus (Table 1), however total diversity is higher since other groups such as an Ostracod and another Diptera larvae were observed but it was not possible to identify them due to their low abundance.
