Anagallis monelli is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of pimpernel, native

Indigenous (ecology)

In biogeography, a species is defined as native to a given region or ecosystem if its presence in that region is the result of only natural processes, with no human intervention. Every natural organism has its own natural range of distribution in which it is regarded as native...

 to the Mediterranean region. It is not to be confused with Anagallis foemina

Anagallis foemina

Anagallis foemina, common name Poorman's Weatherglass, is a low-growing annual herbaceous plant of the genus Anagallis belonging to the Myrsinaceae family.-Etymology:...

, which has very similar blue flower

Flower

A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...

s, but broader leaves and can can be found also in colder climates. In a comparison of DNA sequence

DNA sequence

The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...

s, Anagallis monelli was shown to be most closely related

Phylogenetics

In biology, phylogenetics is the study of evolutionary relatedness among groups of organisms , which is discovered through molecular sequencing data and morphological data matrices...

 to Anagallis foemina. The latter had been thought by many to be closest to Anagallis arvensis, and some authors had even included Anagallis foemina as a subspecies

Subspecies

Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

of Anagallis arvensis.