Sporangioles of Thamnidium
(from MycoAlbum CD by GLB)
Thamnidium is a genus in the order Mucorales of the Zygomycetes. It has a tall sporangiophore bearing a 'Mucor-type' sporangium (with a columella) at its tip. Laterally on the sporangiophore it produces a series of dichotomous branches with the ultimate tips bearing sporangioles (tiny sporangia ) each containing a few spores (sporangiospores) and lacking a columella (see Rhizopus on this). The photomicrograph shows one of these lateral clusters of dichotomous branches. The proper orientation would be 90 clockwise (or 90 anticlockwise!).