Trochetiopsis
Encyclopedia
The flowering plant
genus
Trochetiopsis consists of two extant and one extinct species
endemic
to the island
of Saint Helena
(South Atlantic Ocean
). They were formerly placed in the family
Sterculiaceae
, but this is included in the expanded Malvaceae
in the APG
and most subsequent systematics.
There is evidence from fossil
pollen
that the Trochetiopsis lineage has been on Saint Helena since the late Miocene
(some 9.5 million years).
, but were separated by Marais in 1981 on the basis of geography
and morphological characters. Unlike in Trochetia, the Trochetiopsis flowers have only five stamens, and the sepals generally have appressed sericeous indumentum on their interior faces (although one species, T. melanoxylon, lacks this last character).
The wood
of all the species is attractively coloured and is used in island inlay work.
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...
genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Trochetiopsis consists of two extant and one extinct species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
endemic
Endemic (ecology)
Endemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...
to the island
Island
An island or isle is any piece of sub-continental land that is surrounded by water. Very small islands such as emergent land features on atolls can be called islets, cays or keys. An island in a river or lake may be called an eyot , or holm...
of Saint Helena
Saint Helena
Saint Helena , named after St Helena of Constantinople, is an island of volcanic origin in the South Atlantic Ocean. It is part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha which also includes Ascension Island and the islands of Tristan da Cunha...
(South Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
). They were formerly placed in the 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...
Sterculiaceae
Sterculiaceae
Sterculiaceae is a botanical name for a group of flowering plants at the rank of family, which is now considered obsolete. As is true for any botanical name, the circumscription, status and placement of the taxon has varied with taxonomic point of view...
, but this is included in the expanded Malvaceae
Malvaceae
Malvaceae, or the mallow family, is a family of flowering plants containing over 200 genera with close to 2,300 species. Judd & al. Well known members of this family include okra, jute and cacao...
in the APG
Angiosperm Phylogeny Group
The Angiosperm Phylogeny Group, or APG, refers to an informal international group of systematic botanists who came together to try to establish a consensus on the taxonomy of flowering plants that would reflect new knowledge about plant relationships discovered through phylogenetic studies., three...
and most subsequent systematics.
There is evidence from fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
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...
that the Trochetiopsis lineage has been on Saint Helena since the late Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
(some 9.5 million years).
Description
The species of this genus were formerly included in the genus TrochetiaTrochetia
Trochetia is a genus of flowering plants from the family Malvaceae . They are endemic to the Mascarene Islands.The genus was first described by A.P...
, but were separated by Marais in 1981 on the basis of geography
Geography
Geography is the science that studies the lands, features, inhabitants, and phenomena of Earth. A literal translation would be "to describe or write about the Earth". The first person to use the word "geography" was Eratosthenes...
and morphological characters. Unlike in Trochetia, the Trochetiopsis flowers have only five stamens, and the sepals generally have appressed sericeous indumentum on their interior faces (although one species, T. melanoxylon, lacks this last character).
The wood
Wood
Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...
of all the species is attractively coloured and is used in island inlay work.
Species
There are three species (two living, one extinct), and one named hybrid:- Trochetiopsis erythroxylonTrochetiopsis erythroxylonAlthough the Saint Helena Redwood is now extinct in the wild, it was formerly abundant enough in the upland parts of the island of Saint Helena for early settlers in the 17th century to use the timber to make their homes....
. Extinct in the wild - Trochetiopsis ebenusTrochetiopsis ebenusSaint Helena ebony is a species of flowering plant that is endemic to the island of Saint Helena in the southern Atlantic Ocean. It is not related to the ebony of commerce , but is instead a member of the mallow family, Malvaceae...
. The St Helena ebony (critically endangered in the wild). - Trochetiopsis melanoxylonTrochetiopsis melanoxylonThe Dwarf Ebony of the island of Saint Helena is related to Trochetiopsis ebenus but is now extinct...
- Extinct. - Trochetiopsis x benjaminii (T. erythroxylon x T. ebenus).