Will the conditions of puddle area and time affected the presence of Lymnea sp. ?

I went to collect Lymnea sp around 9 a.m. to 12 p.m. but it show that no presence of Lymnea at the puddle area. I just want to confirm, what made lymnea not appear in the puddle area during this...

16 December 2014 1,811 1 View