''Polanisia erosa'' is a sticky, high
annual herbaceous
Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials.
Definitions of "herb" and "herbaceous"
The fourth edition of ...
species of flowering plant in the ''
Cleome'' family,
Cleomaceae
The Cleomaceae are a small family of flowering plants in the order Brassicales, comprising about 220 species in two genera, '' Cleome'' and '' Cleomella''. These genera were previously included in the family Capparaceae, but were raised to a dis ...
, known by the common name large clammyweed. It has narrow clover-like leaves, and cream-coloured, frilly flowers with a yellowish centre, looking a bit like a small butterfly or a set of elk antlers. It naturally occurs in dry and sandy habitats in Texas and adjacent parts of Arkansas, Louisiana and Oklahoma.
Taxonomy
The American botanist
Thomas Nuttall
Thomas Nuttall (5 January 1786 – 10 September 1859) was an English botanist and zoologist who lived and worked in America from 1808 until 1841.
Nuttall was born in the village of Long Preston, near Settle in the West Riding of Yorkshire a ...
was the first to describe large clammyweed in 1834, which he placed in a new genus and named ''Cristatella erosa''.
Amos Eaton
Amos Eaton (May 17, 1776 – May 10, 1842) was an American botany, botanist, geologist, and educator who is considered the founder of the modern scientific prospectus in education, which was a radical departure from the American liberal arts tra ...
included the species in 1836 in the genus ''Cleome'' as ''C. erosa''. In 1842,
Stephan Endlicher
Stephan Friedrich Ladislaus Endlicher, also known as Endlicher István László (24 June 1804 – 28 March 1849), was an Austrian Empire, Austrian botanist, numismatist and Sinologist. He was a director of the Botanical Garden of Vienna.
Biog ...
, an Austrian botanist who was the director of the
Vienna Botanical Garden moved the species to a new genus and renamed it to ''Cyrbasium erosum'', which is an
illegitimate name
''Nomen illegitimum'' (Latin for illegitimate name) is a technical term used mainly in botany. It is usually abbreviated as ''nom. illeg.'' Although the International Code of Nomenclature for algae, fungi, and plants uses Latin terms as qualif ...
. In 1958
Hugh Iltis concluded the species could better be assigned to the genus ''Polanisia'', a name that has
priority over ''Cristatella'', since it was already erected by
Constantine Samuel Rafinesque
Constantine Samuel Rafinesque-Schmaltz (; 22 October 178318 September 1840) was a French early 19th-century polymath born near Constantinople in the Ottoman Empire and self-educated in France. He traveled as a young man in the United States, ult ...
in 1819, and made the
new combination
In Taxonomy (biology), biological taxonomy, a combinatio nova (abbreviated comb. nov. or n. comb.) refers to the formal renaming of an organism's scientific name when it is transferred to a different genus, reclassified within a different specie ...
''P. erosa''. Iltis distinguished two subtaxa, the
nominate
Nomination is part of the process of selecting a candidate for either election to a public office, or the bestowing of an honor or award. A collection of nominees narrowed from the full list of candidates is a short list.
Political office
In th ...
and subspecies ''breviglandulosa''.
Description
Large clammyweed is a sticky, unscented annual herb of . It has branched or unbranched, green or purple stems with seated glands and
glandular hairs. The long, green or purple
leaf stalks are often at an angle with the leaf blade. The leaf blade consists of three narrow, long and only wide, somewhat fleshy leaflets, the right and left halves more or less folded towards each other (or
conduplicate) with entire margins, a needle-like tip, the underside of the leaf with many, and the upper side with few glands. The
bilaterally symmetrical
Symmetry in biology refers to the symmetry observed in organisms, including plants, animals, fungi, and bacteria. External symmetry can be easily seen by just looking at an organism. For example, the face of a human being has a plane of symme ...
flowers are set in gland-covered
raceme
A raceme () or racemoid is an unbranched, indeterminate growth, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are ...
s that are initially long but that keep growing to when fruits are ripe. Each individual flower is subtended by a
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 consisting of one or three entire bractlets, which have an oval shape and are long. The
stalk of the individual flower is 1−2.3 cm (0.4-0.9 in) long. The four deciduous, eventually deflected, green to purple coloured, hairless
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
Etymology
The term ''sepalum'' ...
s are
lanceolate
The following terms are used to describe leaf plant morphology, morphology in the description and taxonomy (biology), taxonomy of plants. Leaves may be simple (that is, the leaf blade or 'lamina' is undivided) or compound (that is, the leaf blade ...
to
inverted egg-shaped, 2.5–3.5 mm (0.1–0.14 in) long and 0.8–1.3 mm (0.03–0.05 in) wide, with entire margins and a pointy tip. The four petals are mostly creamy white, oblong-ovate, consist of a more yellowish straight and narrow
claw
A claw is a curved, pointed appendage found at the end of a toe or finger in most amniotes (mammals, reptiles, birds). Some invertebrates such as beetles and spiders have somewhat similar fine, hooked structures at the end of the leg or Arthro ...
and a wide
plate. The forward directed lower (