A Latin word often used in taxonomy for species names. Palustris is a Latin word meaning "swampy" or "marshy". It is typically used in scientific names for animals and plants to refer to the typical habitat of the species. Species labelled palustris include:

• The Kingcup or Marsh Marigold, Caltha palustris
• Parnassia palustris, the county flower of Cumberland and Sutherland in the United Kingdom.
• The rattan palm species Calamus palustris
• The Water Violet, Hottonia palustris
• The Marsh Helleborine Epipactis palustris
• The Marsh Lousewort, Pedicularis palustris
• The Marsh Woundwort, Stachys palustris
• The Marsh Violet Viola palustris
• The Southern Yellow Pine Pinus palustris
• The Pin oak, Quercus palustris
• The Common Spike-rush, Eleocharis palustris
• The Fowl bluegrass, Poa palustris
• The Potentilla palustris, otherwise known as the Swamp Cinquefoil
• The Marsh Wren, Cistothorus palustris