Droseraceae
Encyclopedia
Droseraceae is the botanical name
for a family
of flowering plants. The family is also known under its common name, the sundew family.
It consists of carnivorous plant
s: besides the sundew
s, the genus Drosera, it also contains the even more-famous Venus fly trap Dionaea muscipula. The sundews produce sticky substances on their leaves that traps prey, and the Venus fly trap has leaves that form traps that close when disturbed. The third extant genus contains the single species Aldrovanda vesiculosa, which might be characterised as an aquatic Venus flytrap that traps prey underwater.
Despite some debate, taxonomists have tended to include at least two of the three genera, and, in general, all three, in this family since at least 1906. Molecular evidence supports the inclusion of all three, and also shows that the two genera that have traps that snap shut (Dionaea and Aldrovanda) are more closely related to each other than to Drosera, suggesting that snap traps evolved only once.
The family Droseraceae is part of the order Caryophyllales
in the clade core eudicots. The family comprises three extant genera, totaling nearly 200 species.
In the past Drosophyllum lusitanicum has been included in this family, but it is more closely related to the carnivorous liana
Triphyophyllum
and the non-carnivorous liana Ancistrocladus
, and is, thus, classified elsewhere (to be specific, its own monotypic family Drosophyllaceae). Recent molecular and biochemical evidence (see the AP-Website) suggests that the carnivorous taxa in the order Caryophyllales
(the families Droseraceae, Drosophyllaceae, Nepenthaceae, and the species Triphyophyllum peltatum) all belong to the same clade
, which does not consist only of carnivorous plants but also of some non-carnivorous plants such as those in the family Ancistrocladaceae
.
The fossil record of Droseraceae is the richest of any carnivorous plant family. Fossil pollen
has been attributed to several extant as well as extinct
genera, although some are of questionable validity.
Botanical name
A botanical name is a formal scientific name conforming to the International Code of Botanical Nomenclature and, if it concerns a plant cultigen, the additional cultivar and/or Group epithets must conform to the International Code of Nomenclature for Cultivated Plants...
for a family
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 plants. The family is also known under its common name, the sundew family.
It consists of carnivorous plant
Carnivorous plant
Carnivorous plants are plants that derive some or most of their nutrients from trapping and consuming animals or protozoans, typically insects and other arthropods. Carnivorous plants appear adapted to grow in places where the soil is thin or poor in nutrients, especially nitrogen, such as acidic...
s: besides the sundew
Sundew
Drosera, commonly known as the sundews, comprise one of the largest genera of carnivorous plants, with at least 194 species. These members of the family Droseraceae lure, capture, and digest insects using stalked mucilaginous glands covering their leaf surface. The insects are used to supplement...
s, the genus Drosera, it also contains the even more-famous Venus fly trap Dionaea muscipula. The sundews produce sticky substances on their leaves that traps prey, and the Venus fly trap has leaves that form traps that close when disturbed. The third extant genus contains the single species Aldrovanda vesiculosa, which might be characterised as an aquatic Venus flytrap that traps prey underwater.
Despite some debate, taxonomists have tended to include at least two of the three genera, and, in general, all three, in this family since at least 1906. Molecular evidence supports the inclusion of all three, and also shows that the two genera that have traps that snap shut (Dionaea and Aldrovanda) are more closely related to each other than to Drosera, suggesting that snap traps evolved only once.
The family Droseraceae is part of the order Caryophyllales
Caryophyllales
Caryophyllales is an order of flowering plants that includes the cacti, carnations, amaranths, ice plants, and many carnivorous plants. Many members are succulent, having fleshy stems or leaves.-Description:...
in the clade core eudicots. The family comprises three extant genera, totaling nearly 200 species.
In the past Drosophyllum lusitanicum has been included in this family, but it is more closely related to the carnivorous liana
Liana
A liana is any of various long-stemmed, woody vines that are rooted in the soil at ground level and use trees, as well as other means of vertical support, to climb up to the canopy to get access to well-lit areas of the forest. Lianas are especially characteristic of tropical moist deciduous...
Triphyophyllum
Triphyophyllum
Triphyophyllum is a monotypic plant genus, containing the single species Triphyophyllum peltatum. It is native to tropical western Africa, in Sierra Leone and Liberia, growing in tropical rainforests....
and the non-carnivorous liana Ancistrocladus
Ancistrocladus
Ancistrocladus is a little known genus of about 20 species in the monogeneric family Ancistrocladaceae.These are palaeotropical climbing twining plants, found in lowland to submontane, wet to seasonal evergreen or swamp forests, with eleven species occurring in tropical Africa and at least five...
, and is, thus, classified elsewhere (to be specific, its own monotypic family Drosophyllaceae). Recent molecular and biochemical evidence (see the AP-Website) suggests that the carnivorous taxa in the order Caryophyllales
Caryophyllales
Caryophyllales is an order of flowering plants that includes the cacti, carnations, amaranths, ice plants, and many carnivorous plants. Many members are succulent, having fleshy stems or leaves.-Description:...
(the families Droseraceae, Drosophyllaceae, Nepenthaceae, and the species Triphyophyllum peltatum) all belong to the same clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
, which does not consist only of carnivorous plants but also of some non-carnivorous plants such as those in the family Ancistrocladaceae
Ancistrocladaceae
Ancistrocladaceae is the botanical name for a family of flowering plants. Such a family has been widely recognized by taxonomists.The APG II system, of 2003 , also recognizes this family and assigns it to the order Caryophyllales in the clade core eudicots...
.
The fossil record of Droseraceae is the richest of any carnivorous plant family. Fossil pollen
Pollen
Pollen is a fine to coarse powder containing the microgametophytes of seed plants, which produce the male gametes . Pollen grains have a hard coat that protects the sperm cells during the process of their movement from the stamens to the pistil of flowering plants or from the male cone to the...
has been attributed to several extant as well as extinct
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...
genera, although some are of questionable validity.
External links
- Droseraceae in L. Watson and M.J. Dallwitz (1992 onwards). The families of flowering plants: descriptions, illustrations, identification, information retrieval. Version: 30 May 2006. http://delta-intkey.com
- Droseraceae in the Flora of China
- NCBI Taxonomy Browser
- links at CSDL, Texas