How do filter-feeding malacostracans collect microorganisms from sediment?

Filter-feeding malacostracans, such as burrowing and small groundwater species, collect microorganisms and bacteria from sediment primarily by using specialized head and thoracic appendages.1

In these species, the plates of the maxillules, the maxillae, or both are often enlarged and equipped with numerous fine-filtering, or plumose, setae to trap food particles. To facilitate this process, these crustaceans frequently utilize accessory, or baler, plates to direct feeding currents toward the mouth. While many malacostracans use their thoracic legs to gather food, filter feeders rely on these specialized mouthparts—specifically the maxillipeds—to process and pass the collected material to the masticatory mouthparts for consumption.1