width 2µm-5µm: thickness 0.1µm-0.5µm µm
||Archaea Haloquadratum walsbyi
||Young KD. The selective value of bacterial shape. Microbiol Mol Biol Rev. 2006 Sep70(3):660-703 DOI: 10.1128/MMBR.00001-06 p.669 right column 2nd paragraphPubMed ID16959965
|| Bolhuis H, Poele EM, Rodriguez-Valera F. Isolation and cultivation of Walsby's square archaeon. Environ Microbiol. 2004 Dec6(12):1287-91 DOI: 10.1111/j.1462-2920.2004.00692.xPubMed ID15560825
||Primary source abstract: "Here, [investigators] report the isolation and cultivation of the enigmatic square archaeon that [they] propose to name Haloquadratum walsbyi. Pure cultures are easily maintained in simple artificial hypersaline media. Initial growth experiments revealed a tolerance to high concentrations of MgCl(2) (>2 M) in the presence of 3.3 M NaCl."
||P.669 right column 2nd paragraph: "The halotolerant archaea exhibit a curious range of unusual shapes, including triangular cells (ref 144), square cells such as those of Haloarcula quadrata (ref 242), and flat, wafer-shaped cells such as those of Walsby's square archeon (recently named Haloquadratum walsbyi) (primary source). First described by Walsby (ref 350) and recently isolated and grown in pure culture (primary source, ref 35), individual members of these square, flat cells are about 2 to 5 μm wide and 0.1 to 0.5 μm thick (primary source). However, they are most frequently encountered in thin mats measuring up to 40 μm by 40 μm, arranged as though they were sheets of postage stamps (primary source). Floating parallel to the water's surface, these thin cellular mats present a broad and contiguous surface area for exposure to sunlight (primary source). This arrangement maximizes both buoyancy and the total light-gathering area (ref 349)."