In biology, taxonomy is the science of naming, classifying and categorising groups of organisms.
A genus (plural genera) is a group that describes more than one species. For example, there are many species of roses that are part of the Rosa genus, such as the UK native species Rosa canina.
A habitat is an environment where an organism lives.
A microhabitat is a small area with unique conditions differing from the surrounding habitat. For example, where a woodland is a habitat, a rotten branch is a microhabitat.