Diatoms, protists, cyanobacteria, green algae, flagellated algae are all organisms found in puddles.
Puddles are very transitory microenvironments, formed when rainwater accumulates in low spots and gone when the water evaporates or seeps into the ground. Puddle life, adapted to these circumtances with dormant stages (spores or cysts) or the ability to suspend development (larval diapause in invertibrates), is able to survive dry periods and to explode into action as soon as water becomes available. The larval stage of puddle insects is brief, often completed during the puddle's existence, with many adults having taken to wing; the rest die when the puddle dries up.
Two types of puddles form, on pavement and on soil, and their inhabitants are somewhat different as well. Life in pavement puddles, lacking contact with the soil, develops from the airborne spores of microbes and eggs and seeds of higher organisms. Mud puddles, on the other hand, have direct contact with the soiland therefore with all its nutrients and organisms. As you would expect, ther is more life, and more variety in mud puddles than in pavement puddles.
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