Moliço was particularly important in the coastal lagoon of Ria de Aveiro, on the northern Portuguese coast. There it was collected in large quantity by raking from typical sailing boats called moliceiro. The most abundant plant was the eelgrass, including Zostera marina, Z. angustifolia and Z. noltii and some other salt tolerant aquatic plants like Ruppia and Potamogeton.

In the 19th and 20th centuries the collection of moliço had an important role in removing plant nutrients from the Ria de Aveiro helping to stabilize this eutrophic lagoon.

The moliceiro boat is long, pinewood built, belonging to the Mediterranean family of small boats which in Portuguese have the generic name bateira. The most fascinating aspect of these boats is their ornamental paintings following strict rules of popular origin. From WIKIPEDIA