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
  
• MJ : Ice-associated marine habitats
  
  • MJ1 : Sea ice
    
    • MJ11 : Arctic sea ice
      
    • MJ12 : Baltic sea ice
      
  • MJ2 : Freshwater ice
    
  • MJ3 : Brine channels
    
  • MJ4 : Under-ice habitat
    
• N : Coastal habitats
  
• Q : Wetlands
  
• R : Grasslands and lands dominated by forbs, mosses or lichens
  
• S : Heathland, scrub and tundra
  
• T : Forest and other wooded land
  
  • T1 : Deciduous broadleaved forest
    
  • T2 : Broadleaved evergreen forest
    
  • T3 : Coniferous forest
    
  • T4 : Lines of trees, small anthropogenic forests, recently felled forest, early-stage forest and coppice
    
• 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
        
        • U1111 : Proteus anguinus caves
          
        • U1112 : Troglobiont fish 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
    
    • U21 : Boreal and arctic siliceous scree and block field
      
    • U22 : Temperate high-mountain siliceous scree
      
    • U23 : Temperate, lowland to montane siliceous scree
      
    • U24 : Mediterranean siliceous scree
      
    • U25 : Boreal and arctic base-rich scree and block field
      
    • U26 : Temperate high-mountain base-rich scree and moraine
      
    • U27 : Temperate, lowland to montane base-rich scree
      
    • U28 : Western Mediterranean base-rich scree
      
    • U29 : Eastern Mediterranean base-rich scree
      
    • U2A : Crimean base-rich 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
    
    • U51 : Fjell field
      
    • U52 : Polar desert
      
    • U53 : Glacial moraines with very sparse or no vegetation
      
  • U6 : Recent volcanic features
    
• V : Vegetated man-made habitats