Botanical Journal of the Linnean Society, 2004, 145, 251–256. With 8 figures © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society, 2004, 145, 251–256 251 Blackwell Science, LtdOxford, UKBOJBotanical Journal of the Linnean Society0024-4074The Linnean Society of London, 20042004 1452 251256 Original Article A NEW SPECIES OF ARABIS FROM INNER ANATOLIA B. MUTLU *E-mail: mutlu@hacettepe.edu.tr A new species of Arabis (Brassicaceae) from inner Anatolia B ROL MUTLU* Hacettepe University, Faculty of Science, Department of Biology, 06532, Beytepe, Ankara, Turkey Received April 2003; accepted for publication October 2003 A new species of Arabis L., A. erikii Mutlu sp. nov., is described and illustrated. The species is restricted to inner Anatolia, south-west of Sivas. It grows on steppes. Diagnostic morphological characters are given for discrimination from the most similar taxa. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society, 2004, 145, 251–256. ADDITIONAL KEYWORDS: Central Anatolia – conservation – distribution. I ◊ INTRODUCTION Arabis L. had 18 species in Turkey (Cullen, 1965; Davis, Mill & Tan, 1988), but since the most recent revision of the genus (Mutlu, 2002), three new species have been described: A. lycia Parolly & P. Hein (Parolly & Hein, 2000), A. alanyensis H. Duman (Duman, 2001) and A. davisii H. Duman & A. Duran (Duman & Duran, 2001). In addition, two species (A. alpina L. and A. mollis Steven) have been added as new records (Yıldırımlı & Dönmez, 1998; Mutlu & Dönmez, 2003). In this paper, A. erikii is described as a new species. Consequently, the total number of Ara- bis species in Turkey is now 24. In 1997, as part of a revision of the genus Arabis, the author carried out extensive field studies in Cen- tral Anatolia and collected a large number of speci- mens. During these studies, an unusual population was encountered. At first glance in the field, the spec- imens looked like Arabis nova Vill. and Arabis mont- bretiana Boiss. because of their annual habit and sagittate stem leaf. After closer examination and con- sultation with the Flora of Turkey and the East Aegean Islands (Cullen, 1965; Davis et al., 1988), it was real- ized that the specimens were quite different from these two species. They were cross-checked with var- ious accounts of Arabis in relevant floras, i.e. Flora Orientalis (Boissier, 1867), Flora Iranica (Hedge et al., 1968), Flora Europaea (Jones, 1964), Flora of USSR (Komarov, 1939), Flora of Iraq (Hedge & Lemond, 1980) and Flora of Syria, Palestine and Sinai (Post, 1932). Arabis nova and A. montbretiana material col- lected either from the field or kept at Turkish herbaria in Ankara (ANK, GAZI and HUB), Sivas (CUFH), Istanbul (ISTE, ISTO) and Izmir (EGE), was also examined. Authorities for all cited plant names are given according to Authors of Plant Names (Brummitt & Powell, 1992). Morphological examination and light microscope pollen studies were carried out. Pollen slides were prepared following Erdtman (1960). DESCRIPTION Arabis erikii Mutlu sp. nov. (Figs 1–3, 5, 7). Type: B6 Sivas: Kümbet Village, 4 km from Kümbet, 1650 m, 10.vi.1999, Mutlu 4900. (holotype: HUB; isotype: GAZI). Diagnosis: Affinis A. novae Vill. et A. montbretianae Boiss.; sed ab A. nova foliis majoribus internodiis foliis 2-3-plo brevioribus (non longis, foliis aequilongis vel 4-plo brevioribus), racemis fructiferis longioribus, ratione iflorescentiae longitudinis fructuum numero (1.11–) 2 (-3.33) [non (4.31–) 6.66 (-9.55)], seminibus exalatis (non anguste marginatis) differt. Ab A. montbretianae foliis cauilis stellatis, furcatis et dense simpliciter hirtis (non modo stellatis et furca- tis), racemis fructiferis longioribus, ratione inflores-