Maccaffertium modestum
- kingdom: Animalia
- phylum: Arthropoda
- class: Insecta
- order: Ephemeroptera
- family: Heptageniidae
- genus: Maccaffertium
- species: Maccaffertium modestum
- Canada
Gaithersburg
Maryland- Northampton
- Paxton
- West Concord
Massachusetts- Asheville
- Hillsborough
North Carolina- Media
Pennsylvania- Jackson
Tennessee
United States
Baie-Saint-Paul