Narrative
Pimpernel (Anagallis arvensis) is an Eurasian weed that has been accidentally introduced into the United States. This annual is short lived, but this small species can become perennial.The flowers are red to orange. This species was named by Linnaeus.
The orange color will help identify this lifeform.
This lifeform is sometimes considered an undesirable species.
This lifeform is found widely in Eurasia.
This lifeform is widespread in North America.
Anagallis genus is a very widespread genus. There are about 20 smooth herbs in this genus. They have entire leaves on short petioles. There are six species now growing in greater North America.
Primula Family (Primulaceae) is a family of about 800 species with wide distribution. This family is well-represented in greater North America with about 100 species in ten different genera. The Lysimachia and Primula genera account for more than half of the species of the United States.
Primulales Order contains three families.
Dicots (Dicotyledoneae Class) are the predominant group of vascular plants on earth. With the exception of the grasses (Monocots) and the Conifers (Gymnosperms), most of the larger plants that one encounters are Dicots. Dicots are characterized by having a seed with two outer shell coverings.
Some of the more primitive Dicots are the typical hardwood trees (oaks, birches, hickories, etc). The more advanced Dicots include many of the Composite (Aster) Family flowers like the Dandelion, Aster, Thistles, and Sunflowers. Although many Monocots reach a very high degree of specialization, most botanists feel that the Dicots represent the most advanced group of plants.
Seed plants (Phylum Embryophyta) are generally grouped into one large phylum containing three major classes: the Gymnosperms, the Monocots, and the Dicots. (Some scientists separate the Gymnosperms into a separate phylum and refer to the remaining plants as flowering plants or Angiospermae.)
For North American counts of the number of species in each genus and family, the primary reference has been John T. Kartesz, author of A Synonymized Checklist of the Vascular Flora of the United States, Canada, and Greenland (1994). The geographical scope of his lists include, as part of greater North America, Hawaii, Alaska, Greenland, Puerto Rico, and the Virgin Islands.
Kartesz lists 21,757 species of vascular plants comprising the ferns, gymnosperms and flowering plants as being found in greater North America (including Alaska, Hawaii, Greenland, Puerto Rico and the Virgin Islands.
There are estimates within the scientific world that about half of the listed North American seed plants were originally native with the balance being comprised of Eurasian and tropical plants that have become established.
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