
Astragalus petraeus Kar. & Kir., Bull. Soc. Imp. Naturalistes Moscou 15: 333 (1842).Fig. 23≡ Tragacantha petraea (Kar. & Kir.) Kuntze, Revis. Gen. Pl. 2: 947 (1891).= Astragalus irkeschtamii B. Fedtsch., Bot. Mater. Gerb. Bot. Inst. Komarova Akad. Nauk S. S. S. R. 8: 168 (1940).= Astragalus xylorrhizus Bunge, Izv. Imp. Obshch. Lyubit. Estestv. Moskovsk. Univ. 26 (2): 267 (1880).Notes.This species is endemic to Central Asia and distributed throughout Kazakhstan, Kyrgyzstan, and Tajikistan (Podlech and Zarre 2013). We found this species (voucher number: MT 11-6) in rocky, rock-rubbly, and arid slopes of the Kurtogay, Kegen district, occurring at elevations of 1,400 –1,500 m. A. petraeus was morphologically similar to A. arcuatus Kar. & Kir., but differs by racemes with 10–18 flowers, orbicular-ovate (vs. with 5–7 flowers, capitate), leaflets 4–7 pairs, elliptical or oval (vs. 2–3 (– 4) pairs, lanceolate or linear-lanceolate).
