Description: The sponge consists of a basal reticulation of thin-walled tubes which creep and anastomose over the substrate, from which arise numerous, long, free-standing, closely-set oscular tubes which are always provided with lateral diverticula, which may subdivide even further. "It occurs as a bushy form and as an arborescent form." Off-white to grey. Very delicate and soft; "very fragile". The oscules are terminal on erect tubes. "The oscular rim is short."

Distribution: "Arctic; Atlantic coasts of Europe; Mediterranean, etc." "Littoral to 93m."

Distribution Map from NBN: Leucosolenia complicata at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Leucosolenia complicata at iNaturalist World Species Observations database.