subspecies Arabidopsis arenicola (Richardson ex Hook.) Al-Shehbaz, Elven, D.F. Murray & S.I. Warwick — Arctic rock cress (Greenland, Labrador, Nunavut, Québec, Ontario, Manitoba, Saskatchewan) Arabidopsis arenosa (L.) Lawalrée — sand rock cress A. arenosa subsp. arenosa (Europe: native in Austria, Belarus, Bosnia Herzegovina, Bulgaria, Croatia, Czech Republic, NE France, Germany, Hungary, N Italy, Latvia, Lithuania, Macedonia, Poland, Romania, Slovakia, Slovenia, Switzerland, and Ukraine; naturalized in Belgium, Denmark, Estonia, Finland, Netherlands, Norway, Russia and W Siberia, and Sweden; absent in Albania, Greece, C and S Italy, and Turkey) A. arenosa subsp. borbasii (E Belgium, Czech Republic, NE France, Germany, Hungary, Poland, Romania, Slovakia, Switzerland, Ukraine. Doubtfully occurring in Denmark) Arabidopsis cebennensis (D.C.) (SE France) Arabidopsis croatica (Schott) (Bosnia, Croatia) Arabidopsis halleri (L.) A. halleri subsp. halleri (Austria, Croatia, Czech Republic, Germany, N and C Italy, Poland, Romania, Slovakia, Slovenia, Switzerland, and S Ukraine. Probably introduced in N France and extinct in Belgium) A. halleri subsp. ovirensis (Wulfen) (Albania, Austria, NE Italy, Romania, Slovakia, Slovenia, SW Ukraine, Yugoslavia) A. halleri subsp. gemmifera (Matsumura) (Russian Far East, northeastern China, Korea, Japan, and Taiwan) Arabidopsis lyrata (L.) O'Kane & Al-Shehbaz — sand cress A. lyrata subsp. lyrata (NE European Russia, Alaska, Canada (Ontario west into British Columbia), and southeastern and central United States (Vermont south into northern Georgia and Mississippi northward into Missouri and Minnesota)) A. lyrata subsp. petraea (Linnaeus) O'Kane & Al-Shehbaz (Austria, Czech Republic, England, Germany, Hungary, Iceland, Ireland, N. Italy, Norway, Russia (NW Russia, Siberia and Far East), Scotland, Sweden, Ukraine, boreal North America (Alaska and Yukon). Apparently extinct in Poland) A. lyrata subsp. kamchatica (Fischer ex D.C.) O'Kane & Al-Shehbaz (boreal Alaska, Canada (Yukon, Mackenzie District, British Columbia, northern Saskatchewan), Aleutian Islands, eastern Siberia, the Russian Far East, Korea, northern China, Japan, and Taiwan) Arabidopsis neglecta (Schultes) (Carpathian Mountains (Poland, Romania, Slovakia, and adjacent Ukraine)) Arabidopsis pedemontana (Boiss.) (northwestern Italy and, presumably extinct, in adjacent SW Switzerland) Arabidopsis suecica (Fries) Norrlin, Meddel. (Fennoscandinavia and the Baltic region) Arabidopsis thaliana (L.) Heynh. — thale cress (native range almost all Europe to central Asia, now naturalized worldwide) Reclassified species The following species previously placed in Arabidopsis are not currently considered part of the genus. Cytogenetics Cytogenetic analysis has shown the haploid chromosome number (n) is variable and varies across species in the genus: A. thaliana is n=5 and the DNA sequencing of this species was completed in 2001. A. lyrata has n=8