Eleinaceae

Eleinaceae is a small and controversial family of flowering plants proposed to include a group of early-diverging monocots. The circumscription and acceptance of Eleinaceae vary among taxonomists, and it is not universally recognized in current classifications.

Genera: The family is described as containing two genera, Eleina and Paraleleina, with a few described species. The type genus Eleina gives the family its name.

Morphology and characters: Knowledge of Eleinaceae relies largely on fragmentary material, including fossil impressions and a limited number of herbarium specimens. Based on available evidence, the group appears to be herbaceous perennials with simple leaves and small flowers. Some features suggest affinities with early monocots, but diagnostic traits and their variation remain uncertain because of the sparse material.

Phylogeny and relationships: Eleinaceae has been placed in different positions within monocot phylogeny, often described as a stem group to other early-diverging monocots or as a sister lineage to certain clades near Alismatales. Due to limited data, its precise evolutionary position remains unresolved.

Distribution and status: Known records of Eleinaceae come mainly from fossil deposits, with contemporary occurrences either extremely rare or unconfirmed. Consequently, many authorities treat the family as extinct or as a relict lineage with uncertain living representatives.

Taxonomic history and nomenclature: The family was proposed in the late 20th century and has since been the subject of ongoing debate, leading to fluctuating recognition and placement in different classifications.

Etymology: The name Eleinaceae derives from the genus Eleina, the type genus of the family.