Anuraeopsis Fissa Research Articles

First attempt to measure the clearance rate of Anuraeopsis fissa

First attempt to measure the clearance rate of <i>Anuraeopsis fissa</i>

Diel changes in the microstratification of the metalimnetic community in Lake Cisó

The microstratification of the metalimnetic community in Lake Ciso was followed through the diel cycle by means of a fine sampler with syringes spaced at 3 cm intervals. Populations were sharply stratified. The uppermost part of the metalimnion was occupied by the rotifer Anuraeopsis fissa. Next, layers of the ciliate Coleps hirtus and the flagellate Cryptomonas phaseolus were found. Finally, purple sulfur bacteria appeared at the bottom part of the metalimnion. Although in lower abundances, characteristic populations of ciliates were found at each depth: Strombidium inhabited zones with oxygen, while Plagiopyla and Metopus lived at depths with sulfide. Several members of the community moved vertically about 20 cm during the diel cycle. Cryptomonas performed larger vertical migrations of 40 cm. This organism concentrated at the upper metalimnion during the day, and dispersed through the lower metalimnion during the night. At night, Cryptomonas lived in an environment without oxygen and with sulfide concentrations up to 0.6 mM.

Impact of mechanical deweeding on Dal Lake ecosystem

The accelerated nutrient enrichment of Dal Lake, Kashmir has augmented the production of aquatic vegetation to the point where many recreational activities have been severely impaired. For providing relief from nuisance conditions mechanical deweeding was introduced in the lake in 1986. The present study assesses the impact of large scale vegetation removal on water quality, plankton population, macrophyte and fish. The concentrations of electrical conductivity, dissolved oxygen, total phosphorus and nitrate-nitrogen changed significantly immediately after deweeding. Phytoplankton species which increased after deweeding include Amphora ovalis, Cymbella cistula,Cosmarium sp.: also rotifers increased (Anuraeopsis fissa,Brachionus calyciflorus and Monostyla bulla).

Rotifers as Indicators of Water Quality

AbstractA comprehensive survey of the literature on the use of rotifers as bio‐indicators water quality has been made in this article. Brachionus angularis, Trichocerca cylindrica, Polyurthra euryptera, Pompholyx sulcata, Rotaria rotatoria, Filinia longiseta have been designated as indicators of heavy pollution (Eutrophy). Ascomorpha ovalis, Asplanchna herricki, Synchaeta grandis, Ploesoma hudsoni, Anuraeopsis fissa, Monostyla bulla and M. hamata are indicators of fresh and clean waters (Oligotrophy) while a variety of rotifers including Brachionus, Keratella spec, are inhabitants of moderately clean (mesotrophy) waters. However, more and more knowledge regarding morphological variations and physiological conditions of rotifers should be studied and then they can be used as better indicators of environmental quality.

Ecology of rotifers of Surinsar, a subtropical, fresh water lake in Jamme (J &amp; K), India

17 species of rotifers have been recorded from Lake Surinsar, Jammu (J & K), India of which some are either exclusively limnetic (Brachionus angularis, Hexarthra sp., Filinia opliensis), or littoral (Brachionus patulus, M. ventralis, Trichotoria sp., Platyias quadricornis, Lecane (Monostyla) decipiens, L (M), bulla and Lecane sp.) and others (Keratella tropica, Anuraeopsis fissa, Brachionus quadridentatus, B. calyciflorus, Trichocera sp., T. similis, and Polyarthra sp.) seem to be wandering species. Seasonal maxima for both littoral and limnetic zones are reported. Most population maxima are contributed mainly by one or at best two species.

A collection of brachionid rotifers from Kerala

The present paper, which deals with 15 species of brachionid rotifers, forms the first report on the rotifers of Kerala. A new varietyBrachionus forficula keralaiensis has been described.Dipeuchlanis propatula, Anuraeopsis fissa lata andBrachionus caudatus personatus are reported for the first time from India.

New systematical approach to the Japanese planktonic rotatoria

1. A new systematic approach to the Japanese planktonic Rotatoria was made based upon the studies of almost all Japanese species and also on several foreign ones, in treating some 30 taxonomic characters of both female and male. 2. Valid monogonont rotifers hitherto recorded from Japan are about 230 species belonging to some 60 genera. 3. So-called ’valid‘ taxonomic characters are different depending upon the grade of the categories. 4. Taxonomic criteria higher than the family should be taken from the characters of the male, on the contrary, those lower than the genus from those of the female. 5. Species newly established: Anuraeopsis fissa urawensis, A.f. donneri, A. fissa pejleri, Asplanchna priodonta sirakabana, Asplanchnella sieboldii urawensis, Brachionus quadridentatus urawensis, Encentroides nojirensis, Parencentropsis mitti, P. araii, Postclausa hyptopus kurti, Proalinopsis trisegmentum, Ploesoma lynceus lenticularoide, P. lynceus rotundus, Liliferotrocha urawensis, Proalides wulferti, Keratellaeopsis quadratatropica, Synchaeta neapolitanoides, S. okai, Trichotria tetractis remotiprojectis, etc.