Panarctic Flora

671702 Arabis hirsuta (L.) Scop.

• Scop., Fl. Carniol., ed. 2, 2: 30 (1772). - Turritis hirsuta L., Sp. Pl.: 666 (1753). Described from Europe: "Habitat in Sueciæ, Germaniæ, Angliæ". Lectotype: "Erysimo similis hirsuta alba" in Bauhin, Prodr. Theatri Bot.: 42. 1620. (Titz 1976: 496).
• Arabis hirsuta var. subalpestre Ahlfv. in Neuman, Sver. Fl.: 451 (1901). Described from Sweden.
• Arabis allionii auct., non DC. in Lam. & DC., Fl. Franç., éd. 3, 4: 676 (1805).
• ?Arabis sagittata (Bertol.) DC. in Lam. & DC., Fl. Franç., éd. 3, 5: 592 (1815). - Turritis sagittata Bertol., Pl. Genuen.: 79 (1804). Described from central Europe.

2n= (1) 16 (2x). - Europe (N, C). - A few reports, e.g., Burdet (1967) from Norway and Sweden for A. allionii.
(2) 32 (4x). - Europe (N, C). - Numerous reports, partly for var. glaberrima and var. subalpestre.
There are several reports from more southern European regions of 2n = 8 (haploid?), 16, 28, and 30.
Not included: A report of 2n = 64 (8x) for A. borealis (Burdet 1967).

Geography: European - Asian: NOR.

Notes: Jones and Akeroyd (1993), largely based on the extensive studies of Titz (1966, 1968, 1972, 1976, 1978), accepted an Arabis hirsuta group for Europe with seven species, among them A. allionii DC. (diploid) and A. sagittata (Bertol.) DC. (diploid) in central and southern European mountains, A. hirsuta (tetraploid) all over Europe, and A. borealis Andrz. ex Ledeb. (ploidy level not reported) in northern Russia (see Excluded taxa). Titz (1972), in treating the central European taxa, considered A. hirsuta an allotetraploid species derived from two more southern diploid species, one of these A. allionii. The occurrence of diploids also in northern Europe (these reported by Titz as A. allionii) suggests a more complicated situation. Doronkin (1994), in treating the Siberian taxa, accepted a widespread A. sagittata that reaches north to Putorana, but not Taimyr, and included A. borealis in it: "It is practically impossible to draw distinction between species A. sagittata (A. hirsuta auct.) and A. borealis. Characteristics used for differentiation these species are not stable". Berkutenko (1988), for the Russian Far East, synonymised both A. borealis and the North American A. pycnocarpa with A. hirsuta, without comments. We accept only one species, A. hirsuta, for northernmost Eurasia but keep A. pycnocarpa apart. See, however, Jalas (1949) who accepted A. borealis for eastern Fennoscandia.

Three varieties are often recognized in northern Europe but only one of them - var. subalpestre - reaches the Arctic. These races may be local and are proposed included without recognition in A. hirsuta in a Panarctic context.