Amaranthus bigelovii is commonly known as Bigelow's amaranth. It is an annual native to New Mexico, Texas, and Louisiana. Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms (as opposed to folk taxonomy). ... Divisions Green algae Chlorophyta Charophyta Land plants (embryophytes) Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) â Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants... Classes Magnoliopsida - Dicots Liliopsida - Monocots The flowering plants (also called angiosperms) are a major group of land plants. ... Magnoliopsida is the botanical name for a class: this name is formed by replacing the termination -aceae in the name Magnoliaceae by the termination -opsida (Art 16 of the ICBN). ... Families Achatocarpaceae Aizoaceae (Fig-marigold family) Amaranthaceae (amaranth family) Ancistrocladaceae Asteropeiaceae Barbeuiaceae Basellaceae (basella family) Cactaceae (cactus family) Caryophyllaceae (carnation family) Dioncophyllaceae Droseraceae (sundew family) Drosophyllaceae Frankeniaceae Molluginaceae (carpetweed family) Nepenthaceae Nyctaginaceae (four-oclock family) Physenaceae Phytolaccaceae (pokeweed family) Plumbaginaceae (plumbago family) Polygonaceae (buckwheat family) Portulacaceae (purslane family) Rhabdodendraceae... Genera See text The family Amaranthaceae, the Amaranth family, is a taxon of dicotyledon flowering plants included among the Caryophyllales and containing about 65 genera and 900 species. ... Species See text Amaranthus, also known by the common name pigweed, is a widely distributed genus of annual, short-living herb, occurring mostly in temperate and tropical regions, belonging to the Amaranth family (Amaranthaceae). ... In biology, binomial nomenclature is the formal method of naming species. ...