First karyograms of Bromus species, displaying 2n = 6x = 42 chromosomes: a B. catharticus b B. brachyanthera and c B. auleticus. a B. catharticus displayed eleven metacentric (1, 4, 5, 7, 8, 9, 10, 11, 14, 17 and 20) and ten submetacentric chromosomes (2, 3, 6, 12, 13, 15, 16, 18, 19 and 21) b B. brachyanthera exhibited 13 metacentric (1, 2, 4, 5, 6, 9, 10, 13, 15, 16, 17, 19 and 21) and eight submetacentric chromosomes (3, 7, 8, 11, 12, 14, 18 and 20) c B. auleticus presented eleven metacentric (1, 3, 4, 5, 6, 8, 9, 11, 15, 18 and 19) and ten submetacentric chromosomes (2, 7, 10, 12, 13, 14, 16, 17, 20 and 21). Note the morphologically similar chromosomes: a 12–13 in B. catharticus b 11–12 and 15–16 in B. brachyanthera, and c 3–4 in B. auleticus. Bar = 5 µm.