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Plant Taxonomy Glossary

25 essential terms — because precise language is the foundation of clear thinking in Plant Taxonomy.

Showing 25 of 25 terms

A flowering plant that produces seeds enclosed within a fruit (mature ovary). The largest group of land plants.

Related:gymnospermflowerfruit

The Angiosperm Phylogeny Group classification, a molecular-based system for classifying flowering plants into orders and families.

Related:phylogeneticsangiospermcladistics

The two-part naming system for species consisting of a genus name and specific epithet, established by Carl Linnaeus.

Related:LinnaeusspeciesICN

A non-vascular land plant (mosses, liverworts, hornworts) that lacks true roots, stems, and leaves and reproduces via spores.

Related:mossliverwortspore

A monophyletic group consisting of a single ancestor and all its descendants, forming one complete branch of a phylogenetic tree.

Related:monophyleticphylogeneticssynapomorphy

A method of biological classification that groups organisms by shared derived characteristics (synapomorphies) to reconstruct evolutionary trees.

Related:synapomorphyphylogeneticsWilli Hennig

A plant variety that has been selected and cultivated by humans for desirable traits. Cultivar names are written in single quotes after the species name.

Related:varietyhorticulturebinomial nomenclature

An identification tool using a series of paired contrasting statements to progressively narrow down the identity of an unknown organism.

Related:identificationmorphologycouplet

A major taxonomic rank between kingdom and class. In botany, 'division' is used instead of 'phylum' (e.g., Magnoliophyta for flowering plants).

Related:taxonomic hierarchykingdomclass

A species or taxon found naturally only in a specific geographic area and nowhere else in the world.

Related:biogeographyconservationdistribution

A taxonomic rank above species and below family, grouping closely related species sharing common characteristics and ancestry.

Related:speciesfamilybinomial nomenclature

A seed plant that does not produce flowers or fruits, bearing seeds 'naked' on structures such as cone scales. Includes conifers, cycads, and ginkgo.

Related:angiospermconiferseed

A systematically organized collection of dried, pressed plant specimens maintained for taxonomic research and reference.

Related:type specimenvouchertaxonomy

The single specimen designated by the original author as the nomenclatural type of a species at the time of publication.

Related:type specimenICNparatype

Similarity in characteristics between organisms that is not due to shared ancestry but to convergent evolution, parallelism, or reversal.

Related:analogyconvergent evolutionhomology

The formal set of rules governing the scientific naming of algae, fungi, and plants, ensuring universal nomenclatural standards.

Related:binomial nomenclatureprioritytype specimen

Swedish botanist (1707-1778) who formalized binomial nomenclature and the taxonomic hierarchy. Considered the father of modern taxonomy.

Related:binomial nomenclatureSpecies PlantarumSystema Naturae

Describing a group that includes a common ancestor and all of its descendants, forming a natural evolutionary unit.

Related:cladeparaphyleticpolyphyletic

The study of the form and structure of organisms. In plant taxonomy, morphological characters (leaf shape, flower structure, etc.) are used for identification and classification.

Related:anatomyidentificationdichotomous key

Describing a group that includes a common ancestor and some, but not all, of its descendants. Example: traditional 'dicotyledons' exclude monocots.

Related:monophyleticpolyphyleticclade

A branching diagram (dendrogram) that represents the inferred evolutionary relationships among a group of organisms.

Related:cladogramphylogeneticscladistics

Describing an artificial group whose members are derived from two or more separate ancestral lineages, not sharing an immediate common ancestor.

Related:monophyleticparaphyleticconvergent evolution

The fundamental unit of taxonomy, generally defined as a group of organisms capable of interbreeding and producing fertile offspring, or unified by other species concepts (morphological, phylogenetic).

Related:genusspeciationbinomial nomenclature

A shared derived character state that is unique to a particular clade and supports its monophyly in cladistic analysis.

Related:cladisticscladeplesiomorphy

A named group of organisms at any rank in the taxonomic hierarchy (e.g., a species, genus, family, or order). Plural: taxa.

Related:taxonomyclassificationrank
Plant Taxonomy Glossary - Key Terms & Definitions | PiqCue