EDIT

Applied in changeset cdmlib|8f784632435989629cd64692d7c6fc942a68d97f.

Added some tests and did some refactoring. Also removed distributions with status absent from results.
Please review my changes and close if ok.

Created new ticket for aggregated area filter.

Everything works as expected. I tested a scenario which actually the opposite of aggregation: the genus had a distribution which matches the filter but the species did not have any distribution. This species is not returned then. This should also be considered in the aggregation ticket.