How long do they live? Since they grow in very cold conditions and very slowly, some are thought to be 15,000 years old [1]. They are the oldest living animals on our planet (that we know of).
Where are they found? They live in the icy cold waters of the Antarctic Ocean.
What do they eat? They filter in plankton for nutrition.
What do they look like? They look kind of like a cup or a vase. See figure 1.

How do they reproduce? Both with or without sex. They can reproduce asexually when a fragment buds off the main sponge or sexually when eggs and sperm join to form polyps.
How do scientists know how old they are? By analyzing growth marks, using size-frequency-distribution (math), metabolic rate, and modeling [1].

So what are we lacking? There’s no information regarding the nuclear genome of Scolymastra joubini on NCBI (National Center for Biotechnology Information). There’s also not much known about enzymatic activity and reproductive senescence of this species.
Please contact me if you have information about this species.
- Gatti, Susanne. “The rôle of sponges in high-Antarctic carbon and silicon cycling-a modelling approach= Die Rolle der Schwämme im hochantarktischen Kohlenstoff-und Silikatkreislauf-ein Modellierungsansatz.”Berichte zur Polar-und Meeresforschung (Reports on Polar and Marine Research) 434 (2002).