These dealt with marine and freshwater fish health, and microbiological hygiene of molluscan shellfish. This appears to contradict the concept that the ancestral molluscan radula was mineralized. Commonly used are mammalian and molluscan species, pollen and plant macro-remains (seeds and fruits). Teeth in the molluscan radula are also produced by cells termed "odontoblasts". As with other trematodes, "Fasciola" develop in a molluscan intermediate host. The form of the molluscan shell is constrained by the organism's ecology. However they maintained that "Wiwaxia's" feeding apparatus was much more like a molluscan radula. Other molluscan univalved shells have been found in Canada. It is secreted by a part of the molluscan body known as the mantle. Batteries of peg-like teeth enabled "Lepidotes" to crush the shells of its molluscan prey. The hyponome developed from the foot of the molluscan ancestor. The "mantle cavity" is a central feature of molluscan biology. The simplest molluscan reproductive system relies on external fertilization, but with more complex variations. The Indo-Pacific Molluscan Database gives 1,781 records. Journal of Molluscan Studies 77&colon; 273-308.