The spore shown above comes from a fern, which is a representative of the Polypodiaceae family.

Many genera of mosses, lycopods, and ferns produce spores that are more or less triangular in aspect. These spores contain a "Y" shaped suture on their germinal surface, which is called a trilete scar. This scar is related to the spore mother cell splitting into four equivalent reproductive cells in such a way they are all in contact at a single point. These cells form the "Y" shaped mark, or suture, as they carry a remnant of the point of commonality and the lines of contact with adjoining cells when separating.