Melanogaster ("black-bellied") may refer to the following organisms:
- Melanogaster (fungus), a genus of false truffles
- Melanogaster (fly), a genus of Hoverflies
- Latin binomial abbreviations for species
- A. melanogaster (disambiguation)
- D. melanogaster
- T. melanogaster
- B. melanogaster
- Boa constrictor melanogaster, an Ecuadorian boa constrictor species
- P. melanogaster
- Poecilia melanogaster, a black-bellied limia.