👉 Hydrotheca is a genus of plants in the family Rubiaceae, commonly known as wild thistles. These are aquatic plants that grow in shallow water and provide food for fish, birds, and other aquatic animals. In English, "hydro" means water or liquid, while "theca" refers to a plant. Therefore, hydrotheca can be translated as "water thistle". The specific species of this genus include several types of plants, including: 1. Hydro