π βππ§ππππππ is a globally distributed genus of xenophyophores (Foraminifera, Monothalamea) commonly found on soft sediments in abyssal areas. It looks like a maze of dichotomously branching tubes with walls consisting of mineral grains & shells of other foraminifera. Tube lumens are filled with cytoplasmic strands and dark masses of stercomata (waste pellets). Irregular lumps of such tubes are sometimes observed on the surface of freshly recovered sediment samples. The illustrated specimen is a short fragment of π βππ§ππππππ (~1.9 mm long), with an empty shell of a planktonic foram (πΊπππππππ‘ππππ sp.) still attached at one end; originally, it was collected with a multiple corer at 5498 m depth, photographed, and preserved for DNA analysis.
Many outstanding questions regarding these remarkable xenophyophores remain:
- π . πππππππππππ a globally distributed species, like some other deep-sea foraminifera, or there are many related species with blurred morphological boundaries?
- Aspects of its benthic lifestyle: growth dynamics, position with respect to the sediment surface (does it produce an anchor or βrootsβ? is it able to somehow orient itself with respect to the sediment surface?) and its feeding strategy are not exactly known.
- Cytology of π βππ§ππππππ is not fully explored; the only dedicated study involving electron microscopy was published a while ago (Cartwright et al. 1989).
