Haloragaceae
Encyclopedia
Haloragaceae is a dicotyledon
Dicotyledon
The dicotyledons, also known as dicots, are a group of flowering plants whose seed typically has two embryonic leaves or cotyledons. There are around 199,350 species within this group...

 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...

 family in the 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...

 Saxifragales
Saxifragales
Saxifragales is an order of flowering plants. Their closest relatives are a large eudicot group known as the rosids by the definition of rosids given in the APG II classification system. Some authors define the rosids more widely, including Saxifragales as their most basal group. Saxifragales is...

, based on the phylogenetic APG III system
APG III system
The APG III system of flowering plant classification is the third version of a modern, mostly molecular-based, system of plant taxonomy...

. In the 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...

, it was included in the order Haloragales
Haloragales
Haloragales is a botanical name for an order of flowering plants. In the Cronquist system of classification, of 1981, it was placed in subclass Rosidae and had this circumscription:* order Haloragales...

.

Distribution

The distribution of the family is nearly worldwide. The center of species diversity is in Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 where all genera are found excepting Proserpinaca and Laurembergia. The terrestrial taxa are primarily limited to the southern hemisphere
Southern Hemisphere
The Southern Hemisphere is the part of Earth that lies south of the equator. The word hemisphere literally means 'half ball' or "half sphere"...

. Glishcrocaryon, Haloragodendron, Meionectes and Trihaloragis are Australian endemics.

Description

The family consists mostly of herbaceous perennial
Perennial plant
A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials...

s or occasionally annual
Annual plant
An annual plant is a plant that usually germinates, flowers, and dies in a year or season. True annuals will only live longer than a year if they are prevented from setting seed...

s, although there are some woody taxa (Haloragodendron spp.). Some are primarily terrestrial (Glischrocaryon, Gonocarpus, Haloragis, Haloragodendron and Trihaloragis) while others are primarily semiaquatic (Laurembergia) or aquatic (Meionectes, Myriophyllum and Proserpinaca) of freshwater systems. Myriophyllum are usually [monoecious]while most other taxa have hermaphrodite flowers. The flowers are usually small and inconspicuous, but some genera can have more "showy" conspicuous flowers (Haloragodendron, Glischrocaryon). Flowers are usually radial (2-3)-4 parted, petals are usually keeled or hooded when present. In Myriophyllum female flowers usually lack a perianth. They have (2-)4-8 stamens and an inferior ovary of (2-)4 carpels. In Myriophyllum the fruit is a schizocarp of 1-seeded 'nutlets' other genera can have nuts or drupes that can be winged or inflated.

Floral formula:
or

Genera

In the family there are nine genera now recognized, with about 145 species:
  • Glischrocaryon
    Glischrocaryon
    Glischrocaryon is a genus of flowering plants in the family Haloragaceae, endemic to Australia. Species occur in New South Wales, Victoria, South Australia and Western Australia including:*Glischrocaryon angustifolium M.L...

  • Gonocarpus
    Gonocarpus
    Gonocarpus is a genus of flowering plants in the family Haloragaceae. The species, which are native to Australia, New Zealand and Malesia, include :*Gonocarpus acanthocarpus Orchard *Gonocarpus benthamii Orchard...

  • Haloragis
    Haloragis
    Haloragis is a genus of flowering plants in the family Haloragaceae. Some species are known commonly as seaberry and most are native to the southern hemisphere...

  • Haloragodendron, with five species of bushes, endemic to Australia
  • Laurembergia
  • Meionectes
  • Myriophyllum
    Myriophyllum
    Myriophyllum is a genus of about 69 species of freshwater aquatic plants, with a cosmopolitan distribution. The center of diversity for Myriophyllum is Australia with 43 recognized species...

    , with 60 species of water plants
  • Proserpinaca
  • Trihaloragis


The taxa of the earlier family Cercodiaceae and Myriophyllaceae are now included in the family Haloragaceae. Earlier, the genus Gunnera
Gunnera
Gunnera is a genus of herbaceous flowering plants, some of them gigantic. The genus is the only member of the family Gunneraceae.The 40-50 species vary enormously in leaf size...

was included in this family.

External links

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