Nitella opaca (Dark Stonewort) is a species of plants in the family stoneworts. They are associated with freshwater habitat. They are native to Rio Grande Do Sul.
Definition: number of homologous sets of chromosomes in the nucleus or primary chromosome-containing compartment of the cell, each set essentially coding for all the biological traits of the organism.
Definition: This organism produces this material or substance, either during its life or after death. A produces B if some process that occurs in A has output B.
Definition: A group of species that exploit the same food resources, and/or use the same feeding or foraging methods. http://en.wikipedia.org/wiki/Guild_(ecology)
