Whilst birding the Asir mountains of the
Tanoumah area in southwest Saudi Arabia, I came across a plant I could not
identify. It looked like a blue Scarlet Pimpernel but I did not think they
existed. As a result, I asked Irene Linning who is a plant expert and who
previously lived in Saudi Arabia if she could identify it for me. Irene said it
was a Blue Pimpernel Anagallis arvensis ssp foemina a species that grows
widely with flowers 9 mm wide and petals slightly fringed. This is a relative
of the European Anagallis arvensis Scarlet Pimpernel a plant generally
considered a weed. They grow in light soils, though it grows opportunistically
in clayey soils as well. The blue form of Anagallis arvensis can be
difficult to distinguish from Anagallis arvensis ssp foemina, but the
petal margins are diagnostic: whereas foemina has clearly irregular
petal margins with only 5 to 15 glandular hairs, A. arvensis ssp
azurea has 50 to 70 hairs on only slightly irregular margins.
