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URCEOLARIS GROUP 

38 a. Each anterior spine smooth and symmetrical. Lorica thin, but with
      distinct dorsal and ventral plates..............................39

38 b. Each anterior spine on lorica asymmetrical, with shoulder on one
      side............................................................40

39 a. Dorsal surface of lorica smooth. Size 200-300 μm. Mainly benthic,
      often attached to the substrate, but also in open water. In ponds,
      lakes, running water. In freshwater but also in saline water.
      Appears to be confined to alkaline eutrophic waters [2003b].
      Indicator of mesotrophic and eutrophic waters (Sládeček 1983).
      Feeds on unicellular green algae. Rare
      - Muntinglupa Roadside ditch in Tamparan: Lanao del sur,
        Pasig River (rare), Taal Lake.

          Brachionus urceolaris, MULLER 1773
                     [1978a+b, 1986a, 2009a, 2001a, 2011a]

39 b. Dorsal surface of lorica with longitudinal striations and pitting
      on well set-off basal piece. In dystrophic and acid waters - can 

      also grow at neutral pH in the laboratory [2000].
      - Calamba River, IRRI Rice field.

          Brachionus sericus, ROUSSELET 1907 

(syn. B. urceolaris. var. sericus)

           [1999]
 

Rice terraces Ifugao province 1980
 


 40 a. Lorica thin, butwith distinct dorsal and ventral plate.
       Size 150-200 µm. Food mainly unicellular algae:
       Chlorococcales, Euglenoides, but also detritus and bacteria.
       Epizoic, often found attached as phoretic epibionts to
       Moina micrura, Diaphanosoma sarsi and D. excisum (Cladocera)
       Sharma, 1983), using cladocera as an easy means of transport,
       but is not a parasite. Eutrophic indicator (India) and general
       indicator of eutrophic and polytrophic waters (Sládeček (1983).  
                Known for sporadic blooms in the rural areas of peninsular India.
       Occurrence often coincides with the blooming of the cyanobacterium
       (bluegreen alga) Microcystis aeruginosa. Ability for co-existence
       of Brachionus species with cyanobacteria is considered a
       pre-supposition for survival in tropical lakes. Frequently found
       to be infested with thick growths of Chlorococcales (Sharma, 1983).
       Predate on flagellates etc (Wallace et al., 2006).
       In eutrophic ponds, also free swimming in open freshwater,
       sporadic in brackish water.

  - Fishpond in Los Bańos, Calamba River,
              Laguna de Bay, Pasig River (rare), Calamba River, IRRI Rice field.

          Brachionus rubens, EHRENBERG 1838.
                    [1984a, 1999, 2009a]

To 40 b.