Droseraceae

Droseraceae Temporal range: Late Cretaceous – Recent
Venus flytrap
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Core eudicots
Order:	Caryophyllales
Family:	Droseraceae Salisb.
Genera
Aldrovanda Dionaea Drosera †Droserapollis †Droserapites †?Droseridites †Fischeripollis †Palaeoaldrovanda †Saxonipollis

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 plants: besides the sundews, 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.^[1]

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.^[1] 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.^[1]

The family Droseraceae is part of the order Caryophyllales in the clade core eudicots.^[1] 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).^[1] 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.

References

1. ^ ^{a b c d e} Cameron, K. M.; Wurdack, K. J.; Jobson, R. W. (2002), "Molecular evidence for the common origin of snap-traps among carnivorous plants", American Journal of Botany 89 (9): 1503, doi:10.3732/ajb.89.9.1503 

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