How many species of seagrass is there?

There are around 60 species of seagrass belonging to four different families: Zosteraceae, Cymodoceaceae, Ruppiaceae, and Hydrocharitaceae. Each family comprises various genera, and each genus contains multiple seagrass species. Seagrasses are found in shallow waters of tropical and subtropical regions, forming extensive meadows that play crucial ecological roles in coastal ecosystems.