Redherrings, being xenopisces, show the ancestral position of the scrafs. These animals use their scrafs to filter the water for food, before bringing it to the main jaws to be removed using comb-like teeth and to be devoured. The scrafs also have chemical detectors, helping them detect how healthy the water is for them. They have four fins, in a cross-like formation, along with the tail. Being an advanced xenopiscian, the quills in the tail are fused into one plus muscle-supports and rays. They have three gill slits, and their gills are similar to those of a terran fish. They reproduce by spawning.
Redherrings gather in huge shoals to feed on plankton. They are prey for many species, including Urahob fishermen. Using a receded quill at the base of the tail, they can detect vibrations, sort of like a lateral line. They have the same swirling, confusing defence mechanism as terran fish and starlings. They occasionally come to shorelines to gather sand for their skeletons, resulting in a frequent boon of food for coastal habitats.