According to the science journal Nature, the differences between pseudohyphae and hyphae are dictated by the shape of the cells, the location of the septin ring and the septum relative to the mother cell and the displacement of the nucleus from the mother cell. The degree of polarized growth and the degree to which the daughter cells are able to separate into individuals cells also create a distinction between pseudohyphae and hyphae.
Hyphae, the plural form of hypha, are considered the building blocks of most fungi. For instance, they form the body of a mushroom. They are composed of filamentous tubular walls resembling minute threads that are divided into individual cells by septa or septum, the cross-walls of the cell. Individual hyphal cells are long, skinny and highly polarized with no obvious overlap or constrictions between cells. Pseudohyphae, on the other hand, resemble elongated ellipsoids. The ellipsoid-shaped cells remain attached to each other at the constricted septation site as they grow. As a result, the pseudohyphae begin to grow into a branching pattern. The Nature website explains that the placement of the nucleus as the cells grows, along with the degree of cell separation between the new daughter cells, also distinguishes hyphae from pseudohyphae.