Carnivorous Plants

COMMON BUTTERWORT

BOG VIOLET

Pinguicula vulgaris

Bladdwerwort Family [Lentibulariaceae]  

month8May month8jun month8june month8jul month8july

status
statusZnative
 
flower
flower8blue
 
inner
inner8white
 
morph
morph8zygo
 
petals
petalsZ2
 2 (5)
type
typeZspurred
 
stem
stem8round
 
sex
sexZbisexual
 

22nd July 2008, Cragg Vale, Yorkshire. Photo: © RWD
The ovate-oblong leaves (of which there are only basal ones) are between 2 to 8cm long.


13th June 2008, Hayeswater Gill. Photo: © RWD
The pedicels (flower stalks) are between 5 and 18mm long.Note the cup-shaped leaves able to hold water and catch insects, upon which it feeds. The flower petals are looking more like a lampshade here - almost actinomorphic in form. The corollas are between 14mm and 22mm (up to 25mm occasionally) including the spur behind (which itself is between 4 to 7mm long (up to 10mm occasionally). The lowest petal has a short white patch in the throat of the flower.


13th June 2008, Hayeswater Gill. Photo: © RWD
A short spur droops down from the rear of the flower.


12 June 2013, Anglesey, N. Wales. Photo: © Dawn Nelson
Rather than being an abnormal specimen with a stem which splits into two half-way-up, with a flower on each end, rather like Twinflower (Linnaea borealis) this is actually two plants whose juxtaposition gives that impression. Unlike the photo above this one, the true zygomorphic nature of the flower is revealed on these specimens.


12th June 2009, Sticks Pass, Greenside Mines, Glenridding. Photo: © RWD
The purple flower is suspended by a 'three-fingered hand' with two less prominent fingers clasping the rear (which is not connected to the spur at the rear, although in the photo it may appear so). Numerous sticky hairs cover the dark brown single stem.


12 June 2013, Anglesey, N. Wales. Photo: © Dawn Nelson
The flower doesn't spend too long in the 'lampshade' configuration, but collapses to the zygomorphic flattened formation with 2 petals above and three below.. The indigo-coloured sepals with three forward fingers and two rear thumbs is clearly distinguishable here from the short purple spur of the flower behind.


13th June 2008, Hayeswater Gill. Photo: © RWD
Sticky white hairs also populate the inside of the petals, particularly the central lobe of the lower lip.


12th June 2009, Sticks Pass, Greenside Mines, Glenridding. Photo: © RWD
The ovary has but one cell in Butterworts. When setting seed it erects itself.


22nd June 2013, Teesdale. Photo: © Dawn Nelson
Note the starfish-like yellowish-green leaves, which are at the base of the plant only, are cupped, able to hold water and catch insects, the 'soup' upon which it feeds.


31st May 2007, Furness Fells, Coniston. Photo: © RWD
The insects fall foul of the slippy slimy slippy hairs, which have tiny spherical glands atop which ooze the slime.


Hybridizes with: Great Butterwort (aka Large-flowered Butterwort) to produce Pinguicula × scullyi (Pinguicula grandiflora × vulgaris), but this hybrid is found in only one small part of southern Ireland.

Distinguishing Feature : the five finger-shaped leaves at the base of the plant which are cup-shaped, able to hold water, and are slimy to catch insects upon which all butterworts feed. Common butterwort has deep violet flowers.

Likes moist or wet ground, bogs and acidic uplands.

This is a  Carnivorous plant,

It obtains some supplementary sustenance from insects which are entrapped by the sticky mucilage exuded by the slippery glands on short stalks in the cup-shaped leaves, where it 'digests' them using several enzymes which are exuded from other glands on the surface of the leaf (rather than from short stalks with glands atop). These enzymes include amylase, protease, esterase, ribonuclease and phosphatase. As the digestible components of the insect are dissolved and break down they are absorbed by the leaf surface to be used internally. The only parts of the insect that cannot be dissolved by the plants enzymes, for instance, the exo-skeleton, remain littering up the leaf surface.

Unlike tropical species of Butterworts which have heterophyllous leaves (leaves of two sorts depending upon season) the temperate species as exist in the UK are all momophylous (having just one type of leaf). It over-winters as a bud.

No relation to : Butterbur (Petasites hybridus) or White Butterbur (Petasites albus) [plants with similar names in a differing family (Asteraceae)].

Investigations have revealed that the leaves, although they contain no alkaloids, contain the following compounds: p-Coumaric Acid, Caffeic Acid, Ferulic Acid, Sinapic Acid, trans-Cinnamic Acid, Benzoic Acid, Cinnamaldehyde, Catalpol, the flavonoids Apigenin, Hypolaetin, Isocutellarin, Scutellarin and Luteolin.

Some histamines at a concentration of 2-13µg/g were also found in the leaf tissue, and this may account for the reported numbing of lips which encounter the surface of Butterworts.

There are two types of glands on the leaves. Those on raised stalks are secretory cells and exude a sticky mucilage which encases the insect in its struggles. Thus incapacitated, the insect releases nitrogenous compounds which initiate the release of several enzymes by glandular pores in the leaf surface. The enzymes, Acid Phosphatase, Esterase, Ribonuclease, Protease and Amylase, digest the insect into a soup that is absorbed by the same pores in the leaf surface, leaving just the exo-skeleton of the insect on the surface. The enzymes are also re-absorbed by the pores on the leaf surface. Job well done, ready for the next insect to perchance upon the leaf surface.

PYRETHRINS

Although nothing to do specifically with Butterworts, the pyrethins are powerfully neurotoxic towards insects acting as insecticides or in lower doses, insect repellents. They are biodegradable, and moderately safe to animals. Both pyrethrin I and pyrethrin II are chemically based around a strained cyclopropane ring (the triangle) and are produced naturally by the commercially grown plant chrysanthemum cinerariaefolium, from which the insecticide is obtained. It is not used directly, but chemically processed to produce the commercial insecticides permethrin and cypermethrin, which unlike their natural precursors the pyrethrins, contain substituted chlorine atoms which presumably increases potency. The strained three-membered ring, cyclopropane, is likely to be unstable, and to cleave. This is probably responsible for its potency as an insecticide. However, like the anti-fouling paint containing tributyl tin, pyrethrins are extremely toxic to marine life as well as to insects (for which they are targeted), bees and animals such as pets. They are neurotoxins. Symptoms of intoxication by animals include lethargy, muscle twitching, convulsions, seizures and death. The symptoms for mammals and humans are similar but less severe, and include itching due to their allergenic properties. The main saving grace of these pyrethrins, unlike tributyl tin) are that they decompose easily in the environment, and are non-accumulative.


  Pinguicula vulgaris  ⇐ Global Aspect ⇒ Lentibulariaceae  

Distribution
family8bladderwort family8Lentibulariacaea
 BSBI maps
genus8pinguicula
Pinguicula
(Butterworts)

COMMON BUTTERWORT

BOG VIOLET

Pinguicula vulgaris

Bladderwort Family [Lentibulariaceae]  

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