Species, Division and Phylum were coined by John Ray, Eichler and Cuvier, respectively.
Carolus Linnaeus (1707 to 1778), a Swedish naturalist proposed a system to name and organise species and is considered the Father of Taxonomy and also the Father of Modern Botany. He proposed three groups: “Kingdoms” which are divided into “Classes”; these classes are divided into “Orders” which are further divided into “Genera” and then into “Species” (epithet in case of plants).
Species: It is the basic taxonomic category which consists of individuals that resemble more closely than individuals of other species. Members of a particular species have a distinct genetic makeup, can freely interbreed and are reproductively isolated from others. For example, potato (Solanum tuberosum) and mango (Mangifera indica).
Genus: A genus may have one to many species. As per rules of binomial nomenclature, a species can be named only if it is assigned to a genus. All the species of a genus have a number of common features referred to as correlated characters.
Division or Phylum: The term phylum is used for animals, while division is employed for plants. A phylum or division consists of one to many related classes having at least a few characters in common.
In plants, classes, Monocotyledonae and Dicotyledonae are included in the division Angiospermae. Correlated characters are flowering plants and seeds enclosed in a fruit.