Morphological structures of Hydrurus foetidus collected from Shanxi, China observed by light microscope (LM). a, b arbuscular thalli of H. foetidus; c-e  Larger magnifications of the distal part of thalli; f-h Intercalary cells of dense branches, cell division was happening in h; i free cells of loose branches and the polysaccharide sheath were visible; j, k Central axis cells; l newly-generated apical cells. Scare bars: a, b = 200 μm, c–l = 20 μm.