Fat, wriggling grubs that are a staple delicacy of Ferengi cuisine, eaten alive and served at Quark's bar and at family tables on Ferenginar.
Tube grubs are plump larvae eaten by the Ferengi, who prefer them fresh and still moving. Together with slug liver and gree worms they are one of the standard dishes of Ferenginar.
They are seen and mentioned throughout Deep Space Nine. Quark keeps them on hand in his bar and offers them to Ferengi visitors such as Grand Nagus Zek, and they appear on his mother Ishka's table when he and Rom return home in episodes including Family Business. Non-Ferengi tend to find them revolting.
The dish is one of the small touches with which the series builds up Ferengi domestic life: damp, acquisitive and fond of food that fights back.