Trachymedusae
| Trachymedusae | |
|---|---|
| Crossota sp. | |
| Scientific classification | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Cnidaria | 
| Class: | Hydrozoa | 
| Subclass: | Trachylinae | 
| Order: | Trachymedusae Haeckel, 1866 (1879) | 
| Families | |
Trachymedusae belong to the phylum Cnidaria and the class Hydrozoa, among the 30 genera are 5 families containing around 50 species in all, the family Rhopalonematidae has the greatest diversity.