Natura - nature actualia - actual entities Mundus Plinius - physical world Astra Plinius - celestial bodies Universe (Supercluster) Virgo-Hydra-Centaurus Supercluster (Supercluster) Virgo Supercluster (Cluster) Local Group (Galaxy) Milky Way Galaxy veter. (Spiral arm) Orion Arm (Region) Local Bubble Local Interstellar Cloud (Planetary system) Solar System (Planet-satellite system) Earth System (Planet) Earth veter. "spheres" (Earth) (Sphere) Biosphere (Earth) - zone of life "terrestrial and freshwater ecoregions" (Bioregion) New World (Biogeographic realm) Nearctic "freshwater ecoregions" (Nearctic) 01 (Freshwater ecoregion) Alaskan Coastal (Nearctic) 02 (Freshwater ecoregion) Upper Yukon (Nearctic) 03 (Freshwater ecoregion) Alaska & Canada Pacific Coastal (Nearctic) 04 (Freshwater ecoregion) Upper Mackenzie (Nearctic) 05 (Freshwater ecoregion) Lower Mackenzie (Nearctic) 06 (Freshwater ecoregion) Central Arctic Coastal (Nearctic) 07 (Freshwater ecoregion) Upper Saskatchewan (Nearctic) 08 (Freshwater ecoregion) Middle Saskatchewan (Nearctic) 09 (Freshwater ecoregion) English - Winnipeg Lakes (Nearctic) 10 (Freshwater ecoregion) Southern Hudson Bay (Nearctic) 11 (Freshwater ecoregion) Western Hudson Bay (Nearctic) 12 (Freshwater ecoregion) Canadian Arctic Archipelago (Nearctic) 13 (Freshwater ecoregion) Eastern Hudson Bay - Ungava (Nearctic) 14 (Freshwater ecoregion) Gulf of St. Lawrence Coastal Drainages (Nearctic) 15 (Freshwater ecoregion) Canadian Atlantic Islands (Nearctic) 16 (Freshwater ecoregion) Laurentian Great Lakes (Nearctic) 17 (Freshwater ecoregion) St. Lawrence (Nearctic) 18 (Freshwater ecoregion) Northeast US & Southeast Canada Atlantic Drainages (Nearctic) 19 (Freshwater ecoregion) Scotia - Fundy (Nearctic) 20 (Freshwater ecoregion) Columbia Glaciated (Nearctic) 21 (Freshwater ecoregion) Columbia Unglaciated (Nearctic) 22 (Freshwater ecoregion) Upper Snake (Nearctic) 23 (Freshwater ecoregion) Oregon & Northern California Coastal (Nearctic) 24 (Freshwater ecoregion) Oregon Lakes (Nearctic) 25 (Freshwater ecoregion) Sacramento - San Joaquin (Nearctic) 26 (Freshwater ecoregion) Lahontan (Nearctic) 27 (Freshwater ecoregion) Bonneville (Nearctic) 28 (Freshwater ecoregion) Death Valley (Nearctic) 29 (Freshwater ecoregion) Vegas - Virgin (Nearctic) 30 (Freshwater ecoregion) Colorado (Nearctic) 31 (Freshwater ecoregion) Gila (Nearctic) 32 (Freshwater ecoregion) Upper Rio Grande - Bravo (Nearctic) 33 (Freshwater ecoregion) Pecos (Nearctic) 34 (Freshwater ecoregion) Rio Conchos (Nearctic) 35 (Freshwater ecoregion) Lower Rio Grande - Bravo (Nearctic) 36 (Freshwater ecoregion) Cuatro Cienegas (Nearctic) 37 (Freshwater ecoregion) Rio Salado (Nearctic) 38 (Freshwater ecoregion) Rio San Juan (Mexico) (Nearctic) 39 (Freshwater ecoregion) West Texas Gulf (Nearctic) 40 (Freshwater ecoregion) East Texas Gulf (Nearctic) 41 (Freshwater ecoregion) Sabine - Galveston (Nearctic) 42 (Freshwater ecoregion) Upper Missouri (Nearctic) 43 (Freshwater ecoregion) Middle Missouri (Nearctic) 44 (Freshwater ecoregion) US Southern Plains (Nearctic) 45 (Freshwater ecoregion) Ouachita Highlands (Nearctic) 46 (Freshwater ecoregion) Central Prairie (Nearctic) 47 (Freshwater ecoregion) Ozark Highlands (Nearctic) 48 (Freshwater ecoregion) Upper Mississippi (Nearctic) 49 (Freshwater ecoregion) Lower Mississippi (Nearctic) 50 (Freshwater ecoregion) Teays - Old Ohio (Nearctic) 51 (Freshwater ecoregion) Cumberland (Nearctic) 52 (Freshwater ecoregion) Tennessee (Nearctic) 53 (Freshwater ecoregion) Mobile Bay (Nearctic) 54 (Freshwater ecoregion) West Florida Gulf (Nearctic) 55 (Freshwater ecoregion) Apalachicola (Nearctic) 56 (Freshwater ecoregion) Florida Peninsula (Nearctic) 57 (Freshwater ecoregion) Appalachian Piedmont (Nearctic) 58 (Freshwater ecoregion) Chesapeake Bay (Nearctic) 59 (Freshwater ecoregion) Southern California Coastal - Baja California (Nearctic) 60 (Freshwater ecoregion) Sonora (Nearctic) 61 (Freshwater ecoregion) Guzman - Samalayuca (Nearctic) 62 (Freshwater ecoregion) Sinaloa (Nearctic) 63 (Freshwater ecoregion) Mayran-Viesca (Nearctic) 64 (Freshwater ecoregion) Lerma - Chapala (Nearctic) 65 (Freshwater ecoregion) Llanos El Salado (Nearctic) 66 (Freshwater ecoregion) Bermuda (Nearctic)