EUNIS habitat type hierarchical view (marine version 2022 & terrestrial version 2021)

The EUNIS habitat classification review is on-going. Four groups are pending review: Inland waters, Wetlands, Constructed, industrial and other artificial habitats and Complexes.

• M : Marine benthic habitats (MA-MG)
  
• MH : Pelagic water column
  
  • MH1 : Neuston
    
  • MH2 : Completely mixed water column with reduced salinity
    
  • MH3 : Completely mixed water column with full salinity
    
  • MH4 : Partially mixed water column with reduced salinity and medium or long residence time
    
    • MH41 : Arctic partially mixed water column with reduced salinity and medium or long residence time
      
    • MH42 : Atlantic partially mixed water column with reduced salinity and medium or long residence time
      
    • MH43 : Baltic partially mixed water column with reduced salinity and medium or long residence time
      
    • MH44 : Black Sea partially mixed water column with reduced salinity and medium or long residence time
      
    • MH45 : Mediterranean partially mixed water column with reduced salinity and medium or long residence time
      
  • MH5 : Unstratified water column with reduced salinity
    
  • MH6 : Vertically stratified water column with reduced salinity
    
  • MH7 : Fronts in reduced salinity water column
    
    • MH71 : Arctic fronts in reduced salinity water column
      
    • MH72 : Atlantic fronts in reduced salinity water column
      
      • MH721 : Atlantic ephemeral fronts in reduced salinity water column
        
      • MH722 : Atlantic seasonal fronts in reduced salinity water column
        
      • MH723 : Atlantic persistent fronts in reduced salinity water column
        
    • MH73 : Baltic fronts in reduced salinity water column
      
    • MH74 : Black Sea fronts in reduced salinity water column
      
      • MH741 : Black Sea ephemeral fronts in reduced salinity water column
        
      • MH742 : Black Sea seasonal fronts in reduced salinity water column
        
      • MH743 : Black Sea persistent fronts in reduced salinity water column
        
    • MH75 : Mediterranean fronts in reduced salinity water column
      
  • MH8 : Unstratified water column with full salinity
    
    • MH81 : Arctic unstratified water column with full salinity
      
    • MH82 : Atlantic unstratified water column with full salinity
      
    • MH83 : Baltic unstratified water column with full salinity
      
    • MH84 : Black Sea unstratified water column with full salinity
      
    • MH85 : Mediterranean unstratified water column with full salinity
      
  • MH9 : Vertically stratified water column with full salinity
    
  • MHA : Fronts in full salinity water column
    
• MJ : Ice-associated marine habitats
  
• N : Coastal habitats
  
• Q : Wetlands
  
• R : Grasslands and lands dominated by forbs, mosses or lichens
  
  • R1 : Dry grasslands
    
  • R2 : Mesic grasslands
    
  • R3 : Seasonally wet and wet grasslands
    
    • R31 : Mediterranean tall humid inland grassland
      
    • R32 : Mediterranean short moist grassland of lowlands
      
    • R33 : Mediterranean short moist grassland of mountains
      
    • R34 : Submediterranean moist meadow
      
    • R35 : Moist or wet mesotrophic to eutrophic hay meadow
      
    • R36 : Moist or wet mesotrophic to eutrophic pasture
      
    • R37 : Temperate and boreal moist or wet oligotrophic grassland
      
  • R4 : Alpine and subalpine grasslands
    
  • R5 : Forest fringes and clearings and tall forb stands
    
    • R51 : Thermophilous forest fringe of base-rich soils
      
    • R52 : Forest fringe of acidic nutrient-poor soils
      
    • R53 : Macaronesian thermophilous forest fringe
      
    • R54 : Pteridium aquilinum vegetation
      
    • R55 : Lowland moist or wet tall-herb and fern fringe
      
    • R56 : Montane to subalpine moist or wet tall-herb and fern fringe
      
    • R57 : Herbaceous forest clearing vegetation
      
  • R6 : Inland salt steppes and salt marshes
    
  • R7 : Sparsely wooded grasslands
    
• S : Heathland, scrub and tundra
  
• T : Forest and other wooded land
  
• U : Inland habitats with no or little soil and mostly with sparse vegetation
  
  • U1 : Terrestrial underground caves, cave systems, passages and waterbodies
    
    • U11 : Cave
      
      • U111 : Troglobiont vertebrate caves
        
      • U112 : Subtroglophile vertebrate caves
        
      • U113 : Troglobiont invertebrate caves
        
      • U114 : Troglophile invertebrate caves
        
      • U115 : Subtroglophile invertebrate caves
        
      • U116 : Caves without vertebrates or invertebrates
        
      • U117 : Lava tubes
        
    • U12 : Disused underground mines and tunnels
      
  • U2 : Screes
    
  • U3 : Inland cliffs, rock pavements and outcrops
    
  • U4 : Snow or ice-dominated habitats
    
  • U5 : Miscellaneous inland habitats usually with very sparse or no vegetation
    
  • U6 : Recent volcanic features
    
• V : Vegetated man-made habitats