The effect of temperature and salinity on volume of rotifer Brachionus plicatilis complex resting eggs

The effects of temperature(15,20 and 25 ℃)and salinity(5,15 and 30)on resting egg volume of three rotifer species sympatric sibling complex including Brachionus plicatilis Muller(Bm),B.plicatilis Yamamoto(By),and B.rotundiformis Tschugunoff(Br) collected in one coastal lagoon were studied.The volume of the resting eggs was found to be associated with the rotifer size,and to be affected more by changes in temperature and salinity.The volume of the resting eggs was changed with temperature change more in L type rotifers than in S type rotifers.There were larger volumes in Bm and By resting eggs under lower temperature and salinity while larger volumes of Br resting eggs were observed under only medial temperature and salinity.There was no significant difference in resting eggs volume of Bm and By(P0.05).