Final answer:
The term that describes all the species living within the coral reef ecosystem is 'Community.' This includes various fish, invertebrates, and algae that contribute to the coral reef's biodiversity.
Step-by-step explanation:
The term that describes all the species that live in the coral reef ecosystem is Community. A community in biological terms consists of all the populations of various species that live and interact within an ecosystem. Within a coral reef, numerous species such as fish, invertebrates, and algae coexist and form complex relationships, contributing to the ecosystem's overall biodiversity. Coral reefs are one of the most biodiverse ecosystems due to their high species richness and relative species abundance, which are indicators of biodiversity. These ecosystems are not only rich in life but are essential for maintaining the health and stability of marine environments.