Species Fact Sheet - pdf

Galeopsis angustifolia
Status
UK Biodiversity Action Plan Priority species.
Nationally Scarce.
IUCN threat category: Critically endangered (2005).
Taxonomy
Magnoliopsida: Lamiaceae
Scientific name:
Galeopsis angustifolia Ehrh. ex Hoffm.
G. ladanum auct.
Common names:
Red Hemp-nettle, Penboeth Culddail
Galeopsis is one of many genera which has flowers
readily recognisable as typical members of the Deadnettle
family (Lamiaceae or Labiatae) with their strongly
2-lobed flowers, the upper lip being hooded and the
lower lip forming a platform for bees to land on.
Biology & Distribution
It occurs as an arable weed, on waste ground, on open
calcareous soils and scree, quarries, and on coastal sand
and shingle. It was once common as a cornfield weed,
but is declining markedly though still widespread in
southern England and Wales, rarer in Scotland (Preston
et al. 2002). In Wales it has only been seen recently in
three localities on the south coast. Details of all records
are held in the Threatened Plants Database (Lockton &
Whild 2000).
It is a spring-germinating annual which flowers from
July to October which is susceptible to a range of
herbicides (Wilson & King 2003).
Identification & Field survey
Galeopsis is distinguished by being annual plants with
whorls of flowers, with four straight stamens included
under the laterally compressed upper lip and the outer
pair being longer than the inner pair, a strongly 3-lobed
lower lip with two bosses or projections at the base, and
a five-lobed, tubular calyx (Figure 1). The most similar
genera are Lamium, which has only weakly toothed
lower lips, and Stachys, which lacks bosses or projections
at the base of the lower lip.
Six species of Galeopsis have been recorded in Britain.
Galeopsis angustifolia is relatively distinct and readily
recognisable species with red flowers and narrow leaves.
Galeopsis bifida, G. speciosa and G. tetrahit can be
Outer stamens
longer than
inner stamens
Boss
Lower lip 3-lobed
Calyx 5-lobed
Upper lip
Figure 1. Galeopsis angustifolia Detail of flower. Scale bar = 1 cm.
Figure 2. Galeopsis angustifolia (from J. E. Smith & J. Sowerby
(1852). English Botany. London).

immediately distinguished by having rigid, bristl hairs
on the stems which are swollen immediately below each
pair of leaves (with soft hairs and stem not swollen in G.
angustifolia). Galeopsis segetum has pale yellow or whitish
flowers and densely silky hairy leaves.
Galeopsis angustifolia is very similar to the very
rare alien G. ladanum, of which there are very few
confirmed records and is probably also extinct. They
can be distinguished as follows (Townsend 1962; Rich
& Jermy 1998):
G. angustifolia: Leaves broadly ovate to narrowly
linear, though commonly lanceolate, margins
entire to weakly toothed with 1-4 teeth on each
side, sometimes strongly toothed (leaf shape and
serration vary significantly). Calyx whitish or
canescent (rarely sparse), hairs dull harsh white
(lens) due to dense, crowded, coarse papillae
(microscope × 400), if sparse then hairs short
and appressed; tube often tinted brownish or
purplish.
G. ladanum: Leaves broadly ovate to lanceolate,
sharply toothed with 3-7 prominent teeth on
each side. Calyx green, hairs patent, glistening
when fresh (lens), papillae sparse or absent; tube
usually greenish.
Two varieties of G. angustifolia can be recognised,
though there are intermediates (Townsend 1962):
Var. angustifolia: Tall or short, branched above or
below, pubescent to nearly glabrous; calyx with
appressed hairs, ± without glands. Widespread.
Var. calcarea (Schönh.) C. E. Salmon: Rather short,
branched almost from the base, canescent; calyx
with dense patent, long white hairs, usually
glandular around the inflorescence. Widespread
on chalk in E and SE England.
Key characters
Annual, softly hairy, not swollen at the nodes. Leaves
(broadly ovate-) lanceolate (-narrowly linear), margins
entire to weakly toothed with 1-4 teeth on each side,
sometimes strongly toothed. Calyx tubular with five
± equal lobes, whitish or canescent with whitish hairs.
Corolla c. 15-25 mm long, two-lipped, usually red or
reddish purple, lower lip strongly 3-lobed with two
bosses or projections at the base.
References
Lockton, A. J. & Whild, S. (2000). The status of Red
Hemp-nettle, Galeopsis angustifolia Ehrh. ex
Hoffm., in Britain. TPDB report, January 2000.
Preston, C.D., Pearman, D. A. & Dines, T. D. eds.
(2002). New Atlas of the British & Irish flora.
Oxford University Press, Oxford.
Rich, T. C. G. & Jermy, A. C., eds. (1998).
Plant Crib 1998. BSBI, London.
Stace, C. A. (1997). New flora of the British Isles. 2 nd
edition. Cambridge University Press, Cambridge.
Townsend, C. C. (1962). Some notes on Galeopsis
ladanum L. and G. angustifolia Ehrh. ex Hoffm.
Watsonia 5: 143-149.
Wilson, P. & King, M. (2003). Arable Plants - a field
guide. WILDGuides Ltd, Old Basing.
Additional photographs are available on the ARKive
website (http://www.arkive.org/species).