Pinguicula vulgaris L.
Butterwort.
Lentibulariaceae, bladderwort family.
Sp. Pl. 17. 1753
Pinguicula vulgaris var. americana Gray
Vegetative morphology. Plants perennial herbs; 5–10(–15) cm high; with a basal rosette of pale yellowish-green, insectivorous leaves. Taproot present. Caudex present (small). Leaves in a basal tuft; whorled; simple. Leaf blade bases rounded (slightly). Blades 5–30(–35) mm long; 4–12 mm wide. Blades succulent; elliptic and spatulate; veins pinnate. Blades adaxial surface with sessile glands (that make the surface sticky and a trap for small insects. These are held and digested by a secretion from the glands. Under the microscope the glands appear as small (pimple-like) bumps on the leaves).
Reproductive morphology. Flowering stems present. Flowering stems without leaves; hairy (with stumpy mushroom-like glandular hairs, seem at 10–40 X). Flowers solitary; medium-sized, 5–15 mm in diameter or length; zygomorphic. Calyx sepals fused (at the base but free at the apex). Calyx purple (drying brown); herbaceous (glandular); non-accrescent (becoming leathery with age); funnel-form; 5-lobed (the odd sepal posterior); hairy. Petals fused; purple, or blue; 8–15 mm long; spurred (from the lower lip, the spur one-third as long as the petals). Corolla campanulate (two-lipped). Stamens 2; filaments markedly unequal in length. Gynoecia superior. Carpels syncarpous. Styles absent. Placentation free central (or almost so). Ovules numerous and tiny. Fruit with calyx persisting; dry; a capsule; ovoid (flask-shaped); dehiscent. Fruit 2–3 mm long; 1.5–2.5 mm wide; black, or brown; hairy (with glandular hairs similar to those on the leaves). Seeds numerous; minute, 0.7–0.8 mm long x 0.2–0.2 mm wide; brown; with surfaces ridged (honeycomb-like with glandular hairs).
Chromosome information. 2n = 64. Löve and Löve
(1944b, 1948 northern Europe,1956b Iceland, 1982a arctic Canada);
Jørgensen et al. (1958 Greenland); Sokolovskaya and Strelkova (1960
northern Russia); Lövkvist in Weimarck (1963 Sweden); Laane (1967, 1969a
Norway); Sokolovskaya (1972 western Russia); Lövkvist and Hultgård
(1999 Sweden). Several more southern counts.
The aberrant chromosome counts
of 2n = 32 (4x, Casper 1962) and 2n = 50 (Rosenberg 1909,
Tischler 1934) have been discounted as miscounts or based on other plants.
Ploidy levels recorded 8x.
Distribution. Northern hemisphere distribution: circumpolar; Greenland, Canada, United States, Eurasia. Low arctic, or alpine. Range in the Canadian Arctic Archipelago limited. Rare. Arctic Islands: Baffin (in 1989, S. Aiken observed isolated plants of P. vulgaris growing on the north shore of Frobisher Bay near McCormic Inlet, but did not collect a specimen).
Ecology and habitat. Substrates: around the margins of ponds, depressions of low centre polygons; imperfectly drained moist areas; calcareous; silt, clay; with low organic content.
Notes. Karlsson (1986) working in Sweden found that plants of P. vulgaris had annual roots representing about 5–10% of their biomass, but no correlation was found between the size of the reproductive organs and the size of the over-wintering buds. The numbers of seeds produced per capsule varied from 110–140.
Illustrations. • Plants in habitat: Manitoba. Numerous small plants with pale yellow-green leaves and blue zygomorphic flowers. Churchill, Manitoba. Aiken and Brysting 01–007. CAN. • Plant habitat: Baffin. Plants less that 5 cm high with purple flowers and yellow green leaves, growing near the scale bar and at the left of the image. Dry exposed, south facing tundra with sedge. Nunavut, Baffin Island, Soper River Valley, Lapus site. Aiken and Ilse 02–056. CAN. • Close-up of plants: Manitoba. Small plants with pale yellow-green leaves. The black dots are the dead remains of insects on this insectiferous plant. Churchill, Manitoba. Aiken and Brysting 01–007. CAN. • Close-up of plants: Ontario. Plants growing on the north shore of Lake Superior. Photograph by W.D. Bakowsky, Ontario Natural Heritage Information Centre. • Close-up of plant: Baffin.. Plants less that 5 cm high with purple flowers and yellow green leaves, growing near the scale bar and at the left of the image. Dry exposed, south facing tundra with sedge. Nunavut, Baffin Island, Soper River Valley, Lapus site. Aiken and Ilse 02–056. CAN. Scale bar in cm. • Close-up of leaf. Close-up of base of leaves showing surface covered with glands that have trapped an insect. Aiken and Ilses, 02–056. CAN. • Close-up of flowers. Zygomorphic flowers with deep purple-brown, gland dotted calyx, purple- blue petals, with two lips, the lower lip extended with a spurred petal. Churchill, Manitoba. Aiken and Brysting 01–007. CAN. • Close-up of fruit. Note glandular hairs on the flowering stem, and the fused calyx around the developing fruit that is topped with the yellow remains of the stigmas. Churchill, Manitoba. Aiken and Brysting 01–007. CAN. • Arctic Island distribution.
Cite this publication as: ‘S.G. Aiken, M.J. Dallwitz, L.L. Consaul, C.L. McJannet, L.J. Gillespie, R.L. Boles, G.W. Argus, J.M. Gillett, P.J. Scott, R. Elven, M.C. LeBlanc, A.K. Brysting and H. Solstad. 1999 onwards. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 29th April 2003. http://www.mun.ca/biology/delta/arcticf/’. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).
