Myrothamnus | |
---|---|
M. flabellifolia [1] | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Order: | Gunnerales |
Family: | Myrothamnaceae Nied. [2] |
Genus: | Myrothamnus Welw. |
Species | |
Myrothamnus is a genus of flowering plants, consisting of two species [3] of small xerophytic shrubs, in the southern parts of tropical Africa and in Madagascar. Myrothamnus is recognized as the only genus in the family Myrothamnaceae.
Myrothamnaceae was included in order Hamamelidales in the Cronquist system. [4] Molecular systematic studies have suggested that Myrothamnus is not closely related to Hamamelidaceae nor any other family included in that order, but rather is closely related to the morphologically very different Gunnera . In the APG II system (2003) the genus is assigned to family Gunneraceae or to the optionally recognized segregate family Myrothamnaceae. [5] In the APG III system (2009) and APG IV system (2016) the narrower circumscription is preferred, and these two families are considered distinct. [2] [6]
Species of Myrothamnus are dioecious shrubs. [7]
The Laurales are an order of flowering plants. They are magnoliids, related to the Magnoliales.
Hamamelidales is an order of flowering plants formerly accepted in a number of systems of plant taxonomy, including the Cronquist system published in 1968 and 1988. The order is not currently accepted in the Angiosperm Phylogeny Group III system of plant taxonomy, the most widely accepted system as molecular systematic studies have suggested that these families are not closely related to each other. The APG II system (2003) assigns them to several different orders: Hamamelidaceae and Cercidiphyllaceae to Saxifragales, Eupteleaceae to Ranunculales, Platanaceae to Proteales, and Myrothamnaceae to Gunnerales. Additional studies of the chloroplast genome have since confirmed that the families moved into the Saxifragales are closely related.
Illiciales is an order of flowering plants that is not recognized by the current most widely used system of plant classification, the Angiosperm Phylogeny Group's APG III system. The order was comprised differently in various systems of plant taxonomy, but is composed of 2-4 families of shrubs, trees, and lianas native to Australasia, south eastern Asia, and the southeastern United States. The families all contain species with essential oils, and flowers with a perianth with bracts, sepals, and petals incompletely distinguished from each other and not arranged in definite whorls. The families of the order had been variably placed in other orders in different taxonomies.
Ceratophyllaceae is a cosmopolitan family of flowering plants including one living genus commonly found in ponds, marshes, and quiet streams in tropical and in temperate regions. It is the only extant family in the order Ceratophyllales. Species are commonly called coontails or hornworts, although hornwort is also used for unrelated plants of the division Anthocerotophyta.
The Aquifoliales are an order of flowering plants, including the Aquifoliaceae (holly) family, and also the Helwingiaceae and the Phyllonomaceae. In 2001, the families Stemonuraceae and Cardiopteridaceae were added to this order. This circumscription of Aquifoliales was recognized by the Angiosperm Phylogeny Group when they published the APG II system in 2003. In the Cronquist system, there is no Aquifoliales order: the Aquifoliaceae are placed within the order Celastrales and the others are in other families.
The Gunnerales are an order of flowering plants. In the APG III (2009) and APG IV systems (2016), the order contains two genera: Gunnera and Myrothamnus (Myrothamnaceae). In the Cronquist system (1981), the Gunneraceae were in the Haloragales and Myrothamnaceae in the Hamamelidales. DNA analysis proved definitive, but the grouping of the two families was a surprise, given their very dissimilar morphologies. In the older systems of Cronquist and Takhtajan (1997), the Gunneraceae were in the Rosidae, and the Myrothamnaceae were in the Hamamelids. In modern classification systems, such as APG III and APG IV, this order was the first to derive from the core eudicots.
The Buxales are a small order of eudicot flowering plants, recognized by the APG IV system of 2016. The order includes the family Buxaceae; the families Didymelaceae and Haptanthaceae may also be recognized or may be included in the Buxaceae. Many members of the order are evergreen shrubs or trees, although some are herbaceous perennials. They have separate "male" (staminate) and "female" (carpellate) flowers, mostly on the same plant. Some species are of economic importance either for the wood they produce or as ornamental plants.
The Xyridaceae are a family of flowering plants. This family has been recognized by many taxonomists and is known as the yellow-eyed grass family.
The Oxalidaceae, or wood sorrel family, are a small family of five genera of herbaceous plants, shrubs and small trees, with the great majority of the 570 species in the genus Oxalis. Members of this family typically have divided leaves, the leaflets showing "sleep movements", spreading open in light and closing in darkness.
Asphodelaceae is a family of flowering plants in the order Asparagales. Such a family has been recognized by most taxonomists, but the circumscription has varied widely. In its current circumscription in the APG IV system, it includes about 40 genera and 900 known species. The type genus is Asphodelus.
Achariaceae is a family of flowering plants consisting of 31 genera and about 155 species of tropical herbs, shrubs, and trees. The APG IV system has greatly expanded the scope of the family by including many genera previously classified in Flacourtiaceae. Molecular data strongly support the inclusion of this family in the order Malpighiales.
Trimeniaceae is a family of flowering plants recognized by most taxonomists, at least for the past several decades. It is a small family of one genus, Trimenia, with eight known species of woody plants, bearing essential oils. The family is subtropical to tropical and found in Southeast Asia, eastern Australia and on several Pacific Islands.
Euptelea is a genus of two species of flowering plants in the monogeneric family Eupteleaceae. The genus is found from Assam east through China to Japan, and consists of shrubs or small trees:
The Thurniaceae are a family of flowering plants composed of two genera with four species. The botanical name has been recognized by most taxonomists.
The Rapateaceae are a family of flowering plants. The botanical name has been recognized by most taxonomists.
The Muntingiaceae are a family of flowering plants, belonging to the rosid order Malvales. The family consists of three genera: Dicraspidia, Muntingia, and Neotessmannia, each with a single species. They are woody plants of the tropical regions of America. The older Cronquist system placed these genera in the family Tiliaceae, with which they share morphological similarities, but have no evolutionary affinity. Muntingia calabura is widely introduced in tropical regions, because of its edible fruit. Dicraspidia donnell-smithii and Neotessmannia uniflora are the other two species in the family, the latter only known from herbarium specimens.
Ixiolirion is a genus of flowering plants native to central and southwest Asia, first described as a genus in 1821. Recent classifications place the group in the monogeneric family Ixioliriaceae in the order Asparagales of the monocots. In earlier systems of classification, it was usually placed in the family Amaryllidaceae.
Tecophilaeaceae is a family of flowering plants, placed in the order Asparagales of the monocots. It consists of nine genera with a total of 27 species.
Hydrostachys is a genus of about 22 species of flowering plants native to Madagascar and southern and central Africa. It is the only genus in the family Hydrostachyaceae. All species of Hydrostachys are aquatic, growing on rocks in fast-moving water. They have tuberous roots, usually pinnately compound leaves, and highly reduced flowers on dense spikes.
Huaceae is a family of plant in the rosids group, which has been classed in the orders Malpighiales, Malvales, and Violales or in its own order Huales. The APG II system placed it in the clade eurosids I, whereas the APG III system of 2009 and APG IV (2016) place it within the Oxalidales. The family is endemic to central Africa. It contains four species in the following two genera: