Although the morphology of
Weltrichia is highly variable, the overall morphology consists of a central cup-like structure surrounded by a number of radially symmetrical outward projecting rays, to which are attached bivalve-shaped pollen sacs/synangia. The number of rays varies from 9/10 to 30, depending on the species, and the total diameter from to over . Both the cup and rays usually (but not always) have substantial thickness, in some of the thicker species the structure is noticeably woody. The pollen is monocolpate and elliptical. In some species, additional rays project over the central cup, and attractants/resinous substances are present within the cup. The rays also sometimes have ridges,
trichomes, appendages, striae and/or unipinnate (pedicellate) pollen sacs present. Species of
Weltrichia appear to have primarily been
wind pollinated, though some species may have been
pollinated by insects, such as beetles. They were borne by the same plants that also bore female ovulate cones assigned to
Williamsonia. It is unclear whether the parent plants were
monoecious (having both structures on one plant) or
dioecious (where each plant only has one gender of reproductive organ). At least some bearers of
Weltrichia, such as
Kimuriella from Late Jurassic of Japan were low growing
divaricately branching shrubs with a maximum height of 2–3 metres, while others such as
Williamsonia gigas may have been more cycad-like in morphology. == Distribution ==