xasysrasu lujvo

s₁ is a blade/expanse of seagrass (from families Posidoniaceae, Zosteraceae, Hydrocharitaceae, or Cymodoceaceae) of species/strain s₂.

In notes:

srasrzostera: x₁ is a blade/expanse of marine eelgrass (genus Zostera) of species/strain x₂.