Linaceae
Encyclopedia
The Linaceae is a family
of flowering plant
s. The family is cosmopolitan
, and includes approximately 250 species. There are 14 genera, classified into two subfamilies: Linoideae and Hugonioideae (often recognized as a distinct family, the Hugoniaceae).
Leaves of Linaceae are always simple; arrangement varies from alternate (most species) to opposite (in Sclerolinon and some Linum) or whorled (in some Hesperolinon and Linum). The hermaphroditic, actinimorphic flowers are pentameric, or very rarely tetrameric (e.g. Radiola linoides, Linum keniense).
In Linoideae, the largest genus is Linum
, the flaxes, with 180-200 species including the cultivated flax
, Linum usitatissimum. Members of Linoideae include herbaceous annuals and perennials as well as woody subshrubs, shrubs, and small trees (Tirpitzia) inhabiting temperate and tropical latitudes of Eurasia, Africa, Australia, and the Americas. The largest genus of Hugonioideae is Hugonia (~40 spp); Hugonioideae are woody vines, shrubs, and trees and are almost entirely tropical in distribution. In addition to their growth habits and geographic distributions, Linoideae and Hugonioideae can be differentiated by the number of fertile stamens (5 in Linoideae, 10 in Hugonioideae) and fruit type (capsules in Linoideae, fleshy drupe-like fruits in Hugonioideae).
Genera in subfamily Linoideae
Genera in subfamily Hugonioideae
Under the old Cronquist system
of classifying the flowering plants, the Linaceae was placed in its own order
Linales
. Modern classifications place it in the order Malpighiales
.
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
of flowering plant
Flowering plant
The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...
s. The family is cosmopolitan
Cosmopolitan distribution
In biogeography, a taxon is said to have a cosmopolitan distribution if its range extends across all or most of the world in appropriate habitats. For instance, the killer whale has a cosmopolitan distribution, extending over most of the world's oceans. Other examples include humans, the lichen...
, and includes approximately 250 species. There are 14 genera, classified into two subfamilies: Linoideae and Hugonioideae (often recognized as a distinct family, the Hugoniaceae).
Leaves of Linaceae are always simple; arrangement varies from alternate (most species) to opposite (in Sclerolinon and some Linum) or whorled (in some Hesperolinon and Linum). The hermaphroditic, actinimorphic flowers are pentameric, or very rarely tetrameric (e.g. Radiola linoides, Linum keniense).
In Linoideae, the largest genus is Linum
Linum
Linum is a genus of approximately 200 species in the flowering plant family Linaceae, native to temperate and subtropical regions of the world. It includes the Common Flax Linum (flax) is a genus of approximately 200 species in the flowering plant family Linaceae, native to temperate and...
, the flaxes, with 180-200 species including the cultivated flax
Flax
Flax is a member of the genus Linum in the family Linaceae. It is native to the region extending from the eastern Mediterranean to India and was probably first domesticated in the Fertile Crescent...
, Linum usitatissimum. Members of Linoideae include herbaceous annuals and perennials as well as woody subshrubs, shrubs, and small trees (Tirpitzia) inhabiting temperate and tropical latitudes of Eurasia, Africa, Australia, and the Americas. The largest genus of Hugonioideae is Hugonia (~40 spp); Hugonioideae are woody vines, shrubs, and trees and are almost entirely tropical in distribution. In addition to their growth habits and geographic distributions, Linoideae and Hugonioideae can be differentiated by the number of fertile stamens (5 in Linoideae, 10 in Hugonioideae) and fruit type (capsules in Linoideae, fleshy drupe-like fruits in Hugonioideae).
Genera in subfamily Linoideae
- Anisadenia
- Cliococca
- HesperolinonHesperolinonHesperolinon is a genus in the family Linaceae, whose common genus name is western flax, in reference to their distribution along the west coast of North America. There are 13 known species within this genus of wildflowers, most of which are limited to serpentine soil habitats within California, USA...
- LinumLinumLinum is a genus of approximately 200 species in the flowering plant family Linaceae, native to temperate and subtropical regions of the world. It includes the Common Flax Linum (flax) is a genus of approximately 200 species in the flowering plant family Linaceae, native to temperate and...
- Radiola
- Reinwardtia
- SclerolinonSclerolinonSclerolinon is a monotypic genus of flowering plants in the flax family containing the single species Sclerolinon digynum, which is known by the common name northwestern yellowflax. It is native to the western United States where it is known from Washington and Idaho through central California;...
- Tirpitzia
Genera in subfamily Hugonioideae
- Durandea
- Hebepetalum
- HugoniaHugoniaHugonia is a genus of plant in family Linaceae.Species include:* Hugonia macrophylla, Oliv.* Hugonia micans, Engl....
- Indorouchera
- Philbornea
- Roucheria
Under the old Cronquist system
Cronquist system
The Cronquist system is a taxonomic classification system of flowering plants. It was developed by Arthur Cronquist in his texts An Integrated System of Classification of Flowering Plants and The Evolution and Classification of Flowering Plants .Cronquist's system places flowering plants into two...
of classifying the flowering plants, the Linaceae was placed in its own order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
Linales
Linales
Linales is a botanical name of an order of flowering plants. The Cronquist system used this name for an order placed in subclass Rosidae with the following circumscription :* order Linales*: family Erythroxylaceae...
. Modern classifications place it in the order Malpighiales
Malpighiales
Malpighiales is one of the largest orders of flowering plants, containing about 16000 species, approximately 7.8% of the eudicots. The order is very diverse and hard to recognize except with molecular phylogenetic evidence. It is not part of any of the classification systems that are based only on...
.