''Blackstonia perfoliata'' or yellow-wort is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of
flowering plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...
in the family
Gentianaceae
Gentianaceae is a family of flowering plants of 103 genera and about 1600 species.
Etymology
The family takes its name from the genus '' Gentiana'', named after the Illyrian king Gentius.
Distribution
Distribution is cosmopolitan.
Characteri ...
found around the
Mediterranean Basin, but extending into northwestern
Europe
Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirel ...
.
Description
Yellow-wort grows tall, with stiff, branching stems. The leaves are
glaucous, opposite and entire, the upper ones
perfoliate
The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...
, being united at the base. It bears terminal
cymes of bright yellow, stalked flowers, across. The
calyx is deeply divided into 6–10 linear lobes or
sepal
A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coine ...
s, spirally arranged, free or nearly free from each other at the base and shorter than the
corolla. The petals number six to ten and form a short tube. There are six to ten adherent
stamens and a two-lobed
stigma.
[McClintock D. and Fitter, R. ''The Pocket Guide to Wildflowers''. Collins (1956)]
Ecology
This species is found in chalk or limestone turf and on dunes. It flowers from June to October in Britain where it is widespread but not common.
[
Pathogens affecting ''B. perfoliata'' include '' Peronospora chlorae''.]
left
References
{{Taxonbar, from=Q159623
Gentianaceae
Flora of Europe
Flora of Lebanon
Taxa named by Carl Linnaeus