One of the most intelligent invertebrate animal is the octopus. These animals belong to the cephalopod class of molluscs. These animals demonstrate relatively complex reasoning especially when capturing prey. They also demonstrate their intelligence by their communicating skills and some even show signs of learning.
Genus represents taxonomic rank above species and below family. When organisms belong to the same genus, they must be of the same phyla, but may be in different species. In binomial nomenclature it is the generic name shared by the group of close relative.
Ecosystem and pond,
not sure though but good luck !