'' Vexatorella '' is a
genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
containing four
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
of
flowering plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...
, commonly known as vexators, in the
family
Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
Proteaceae
The Proteaceae form a family (biology), family of flowering plants predominantly distributed in the Southern Hemisphere. The family comprises 83 genus, genera with about 1,660 known species. Australia and South Africa have the greatest concentr ...
. The genus is
endemic
Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...
to the
Cape Floristic Region
The Cape Floral Region is a floristic region located near the southern tip of South Africa. It is the only floristic region of the Cape Floristic Kingdom, and includes only one floristic province, known as the Cape Floristic Province.
The Cap ...
of
South Africa
South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...
. The name means “little trouble-maker”, given with reference to the initial difficulties of placing ''V. latebrosa'' within the family. All species are
shrub
A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...
s which occur in dry
fynbos
Fynbos (; , ) is a small belt of natural shrubland or heathland vegetation located in the Western Cape and Eastern Cape provinces of South Africa. The area is predominantly coastal and mountainous, with a Mediterranean climate. The fynbos ...
habitats on the fringes of the
Succulent Karoo
The Succulent Karoo is an terrestrial ecoregion, ecoregion defined by the World Wide Fund for Nature to include regions of deserts and xeric shrublands, desert in South Africa and Namibia, and a biodiversity hotspot. The geographic area chosen ...
ecoregion
An ecoregion (ecological region) is an ecological and geographic area that exists on multiple different levels, defined by type, quality, and quantity of environmental resources. Ecoregions cover relatively large areas of land or water, and c ...
. The
inflorescence
In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...
s are similar to those of the related
leucospermum
''Leucospermum'' commonly known as pincushions, is a genus of evergreen upright, sometimes creeping shrubs that is assigned to the Proteaceae, with currently 48 known species.
The shrubs mostly have a single stem at their base, but some species ...
s but also share features of the
leucadendron
''Leucadendron'' is a genus of about 80 species of flowering plants in the family Proteaceae, endemic to the Cape Provinces and KwaZulu-Natal in South Africa, where they are a prominent part of the fynbos ecoregion and vegetation type.
Desc ...
s, with the floral
bract
In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale.
Bracts are usually different from foliage leaves in size, color, shape or texture. They also lo ...
s becoming woody and enlarged following pollination. The flowers are insect-pollinated, with the seeds dispersed by
ant
Ants are Eusociality, eusocial insects of the Family (biology), family Formicidae and, along with the related wasps and bees, belong to the Taxonomy (biology), order Hymenoptera. Ants evolved from Vespoidea, vespoid wasp ancestors in the Cre ...
s (
myrmecochory
Myrmecochory ( (sometimes myrmechory); from ("ant") and ''khoreíā'' ("circular dance") is seed dispersal by ants, an ecologically significant Myrmecophily, ant–plant Biological interaction, interaction with worldwide distribution. Most ...
).
[
]
Description
Vexators are upright or spreading evergreen
In botany, an evergreen is a plant which has Leaf, foliage that remains green and functional throughout the year. This contrasts with deciduous plants, which lose their foliage completely during the winter or dry season. Consisting of many diffe ...
shrubs with alternately set, narrow, spade-shaped leaves ending bluntly in a bony tip, with an entire margin, and greyish or bluish in colour. The stalked
Stalking is unwanted and/or repeated surveillance or contact by an individual or group toward another person. Stalking behaviors are interrelated to harassment and intimidation and may include following the victim in person or monitoring th ...
flower heads are mostly set individually, sometimes with two to six together at the end of the stems, opening from the center outwards. The individual flowers are 4-merous, star symmetrical and hermaphrodite
A hermaphrodite () is a sexually reproducing organism that produces both male and female gametes. Animal species in which individuals are either male or female are gonochoric, which is the opposite of hermaphroditic.
The individuals of many ...
. The four perianth
The perianth (perigonium, perigon or perigone in monocots) is the non-reproductive part of the flower. It is a structure that forms an envelope surrounding the sexual organs, consisting of the calyx (sepals) and the corolla (petals) or tepal ...
segments are pink or cream-coloured, and have a sweet smell. From their center, a straight style
Style, or styles may refer to:
Film and television
* ''Style'' (2001 film), a Hindi film starring Sharman Joshi, Riya Sen, Sahil Khan and Shilpi Mudgal
* ''Style'' (2002 film), a Tamil drama film
* ''Style'' (2004 film), a Burmese film
* '' ...
emerges that is hairless or powdery. The thickened part at its tip called pollen presenter
A pollen-presenter is an area on the tip of the Stigma_(botany)#Style, style in flowers of plants of the family Proteaceae on which the Stamen#Morphology_and_terminology, anthers release their pollen prior to anthesis. To ensure pollination, the st ...
is cleft at its tip. The ovary
The ovary () is a gonad in the female reproductive system that produces ova; when released, an ovum travels through the fallopian tube/ oviduct into the uterus. There is an ovary on the left and the right side of the body. The ovaries are end ...
is egg- to bottle-shaped, consists of one carpel
Gynoecium (; ; : gynoecia) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more ...
and contains just one cavity
Cavity may refer to:
Biology and healthcare
*Body cavity, a fluid-filled space in many animals where organs typically develop
**Gastrovascular cavity, the primary organ of digestion and circulation in cnidarians and flatworms
*Dental cavity or too ...
with one hanging primordial seed. The ovary is subtended by four free awl-shaped scales. The fruit
In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering.
Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...
is an egg-shaped hairless or powdery achene
An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple fruit, simple dry fruits, dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and Dehi ...
, that is beaked at its tip, and blunt and wrinkly at its base. The bracteoles that support the individual flowers become woody after flowering, a character that set ''Vexatorella'' apart from ''Leucospermum
''Leucospermum'' commonly known as pincushions, is a genus of evergreen upright, sometimes creeping shrubs that is assigned to the Proteaceae, with currently 48 known species.
The shrubs mostly have a single stem at their base, but some species ...
'' except for '' L. secundifolium'' that also develops woody bracteoles.
Taxonomy
Comparison of homologous DNA has increased the insight in the phylogenetic relationships between the Proteaceae. ''Vexatorella'' belongs to a group that (except for '' Leucospermum saxosum'') further only consists of genera endemic to the Cape Floristic Region
The Cape Floral Region is a floristic region located near the southern tip of South Africa. It is the only floristic region of the Cape Floristic Kingdom, and includes only one floristic province, known as the Cape Floristic Province.
The Cap ...
, that together constitute the subtribe
Subtribe is a taxonomic category ranking which is below the rank of tribe and above genus. The standard suffix for a subtribe is -ina (in animals) or -inae (in plants). The first use of this word dates back to the late 19th century. An example of ...
Leucadendrinae. ''Vexatorella'' is the closest relative of ''Paranomus
''Paranomus'' is a genus of 18 species of flowering plants, commonly known as "sceptres", in the protea family. It is endemic to the Cape Floristic Region of South Africa.
Distribution and habitat
The species occur mainly in mountainous areas o ...
''. The genera ''Sorocephalus
'' Sorocephalus '' is a genus containing 11 species of flowering plants, commonly known as powderpuffs, in the family Proteaceae. The name means “heaped head”. The genus is endemic to the Cape Floristic Region of South Africa, more particular ...
'' and ''Spatalla
''Spatalla'' is a genus containing 20 species of flowering plants, commonly known as "spoons", in the family (biology), family Proteaceae. The genus is endemism, endemic to the Cape Floristic Region of South Africa where it is associated with fyn ...
'' are the sister group
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree.
Definition
The expression is most easily illustrated by a cladogram:
Taxon A and ...
to the ''Vexatorella'' and ''Paranomus''. The following trees together represent those insights.
The described subtaxa are:
Conservation
Of the four species and two subspecies, the continued survival of three taxa, ''Vexatorella amoena'' and of ''V. obtusata'' both subsp. ''albomontana'' and ''obtusata'', is considered to be of least concern
A least-concern species is a species that has been evaluated and categorized by the International Union for Conservation of Nature (IUCN) as not being a focus of wildlife conservation because the specific species is still plentiful in the wil ...
. ''V. alpina'' is thought to be a near-threatened species
A near-threatened species is a species which has been categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature (IUCN) as that may be vulnerable to endangerment in the near future, but it does not currently qu ...
. ''Vexatorella latebrosa'' on the other hand regarded as being critically endangered
An IUCN Red List critically endangered (CR or sometimes CE) species is one that has been categorized by the International Union for Conservation of Nature as facing an extremely high risk of extinction in the wild. As of December 2023, of t ...
.
References
{{Taxonbar, from=Q10389983
Proteaceae genera
Endemic flora of the Cape Provinces