|Scrophulariaceae - Figwort Family
Speedwell (Veronica) - this looks like Veronica chamaedrys (Germander speedwell)
Common Toadflax (Linaria vulgaris)
Common Toadflax is also known as the wild snapdragon due to its resemblance to the
snapdragon familiar in gardens which opens and closes like a pair of jaws when gently
squeezed from the sides. This mechanism is to ensure some selectivity in choice of pollinator.
potential pollinating insects land on the lower lip or palate and only insects heavy enough to
depress the palate enough to open the floral tube can gain access to the pollen and nectar.
Linaria vulgaris. Note the nectar which is visible in the spurs.
The Scrophulariaceae includes some well-known and attractive plants, such as speedwells
(Veronica), Foxglove (Digitalis purpurea), Toadflax (Linaria) and snapdragons (Antirrhinum,
now included in the family Plantaginaceae or plantain family on the basis of DNA analysis but
here we prefer to use field taxonomy).
Two orange hairy ridges form a channel (of about 1 mm diameter) to guide the proboscis of
the visiting insect. Only insects with long enough proboscises will ordinarily be able to reach
the nectar, in this case certain bees. The bee also needs sufficient strength to prize apart the
opening to the corolla (petal tube). Whilst feeding, the back of the bee may deposit any pollen
on the stigma and collect any pollen from the anthers.
The copious quantities of nectar that can be seen in Linaria vulgaris have made it prone to
nectar robbery. According to one study, short-tongued bees will steel the nectar without
pollinating the plant, by biting a hole in the corolla, whilst long-tongued bees behave as
genuine pollinators (Stout, J.C., J.A. Allen and D. Goulson, 2000. Nectar robbing, forager
efficiency and seed set: Bumblebees foraging on the self incompatible plant Linaria vulgaris
(Scrophulariaceae). Acta Oecologica 21: 277−283). This study found that 96% of open
flowers (in southern England, UK) suffered nectar robbery! These flowers are self-
incompatible and so cannot self-pollinate. However, despite the high incidence of nectar
robbery, seed set remained high as genuine pollinators were sufficiently abundant.
Above: The Foxglove (Digitalis purpurea). Image courtesy of:
Foolip, Wikimedia Commons.
Article last updated:
28 March 2015
6 June 2015
26 March 2016
16 April 2016
24 July 2016
23 Sept 2016
Each plant produces an average of 30 000 seeds, of which about half are viable. Each seed is
surrounded by a broad wing, however, experiments suggest that wind dispersal is of limited
importance, as most seeds fall close to the parent plant.
Above: Ivy-leaved Toadflax, Cymbalaria muralis. A more recent taxonomy places this genus
in the Plantain family (Plantaginaceae). Unlike the Common Toadflax, the Ivy-leaved
Toadflax is self-compatible and frequently self-pollinates.
Veronica persica (Common Field Speedwell) - close-up
Speedwells (Veronica) are not the easiest plants to identify to species level and examination of both flowering and fruiting
stages is helpful. However, this plant was distinctive in having each flower born in a leaf (bract) axil on a pedicel (flower
stalk) which is much longer than the leaf. The lower petal (lower lip) was also clearly white Combined with leaf shape and
flowering time (March: Veronica persica flowers all year round, though several other species also flower in March) makes
this determination likely.
Above: trichomes (hairs) were conspicuous on the reddish
stems, generally arranged in one wide and one pair of
narrow rows but with scattered trichomes between the rows.
These possibly serve as an 'assault course' to make it hard
for hostile insects to climb the stem without falling off.
Trichomes on the petiole (above) and on the leaf
(scattered mostly between the veins) are stouter and look
like they may be secretory. Short trichomes also occur
around the leaf margin (these possible serve to deter those
specialist herbivorous insects which target the leaf margins).
Above: a flower bud: the blue-white corolla is visible inside
the green sepals (calyx). Two stamens with white filaments
(swollen considerably around their mid-section for some
unknown purpose) can be seen, each bearing a pair of
anther locules (purplish in colour) which have split vertically
into two valves to release the white pollen. Right: the lower
lip has been displaced to the right (whitish colour).
Above: the stamen filaments anchor at the base of the upper lip. Around their base, extending onto the lower
lip, are 'icicle-like' trichomes filled with clear liquid to give them a beautiful glassy appearance (more beautiful
when viewed in real life as the photograph is only focused in a narrow plane), some of it already secreted as
droplets. This liquid is nectar and the nectary thus consists of specialised secretory trichomes born on the
Small bees visiting the flowers of Speedwell reportedly usually land on one of the projecting stamens, clinging to
it and potentially picking up some of the sticky pollen. The stamen filament has a flexible base and so droops
under the bee's weight, lowering the underside of the bee onto the stigma, to potentially deposit pollen the bee
may be carrying from an earlier visit to another flower.