Filterers

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Seafloor teeming with life – as seen from end of the Dive sequence – with diverse sponges and algae of various shapes, sizes and colors. Tiny particles (white cloud) sink through the water towards the bottom.

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Camera advances towards a group of filter-feeders and starts rotating around it. The towering sponges at the center of the cluster belong to Hazelia (tall, tubular forms with large openings at the top).

Around the periphery, several disc-shaped Choia sponges, with long spicules arranged radially, lay next to Pirania, another distinctive sponge of medium size, but with very elongate spicules that seem to pierce its body in all directions.

As the camera continues its rotation, juveniles of the cactus-like animal Chancelloria - characterized by a series of pronounced star-shaped elements covering its body - can be seen at the base of the tall Hazelia sponges.

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Just beside Chancelloria, Diagoniella, a conical sponge with thin walls and a distinct pattern of crossed spicules, harbors Hallucigenia, a small and slow moving animal with long dorsal spines and skinny legs. Hallucigenia is distantly related to modern day velvet worms and may have fed on sponges.

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As the camera continues its journey around the cluster it encounters Mackenzia, an animal resembling a modern sea anemone attached to the seafloor. Mackenzia shows remarkable flexibility and seems to be pumping water through a central opening at the top.

Next to Mackenzia, the sponge Eiffelia is easy to spot thanks to its striking ball-like shape and network of star-shaped spicules.

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As the rotation is almost complete, the camera travels along a patch of smaller sponges and brachiopods (filter-feeding animals known today as lamp shells). Five species of brachiopods inhabit this area. In the foreground, a single Nisusia can partially be seen just behind Eiffelia; beyond, on a short stalk, a single specimen of Diraphora with faint radial ribs is attached next to a cluster of smaller shells of Acrothyra. A bit further back, Micromitra, a small brachiopod with long hair-like setae sticking out from between the shell valves, can be seen hanging on a very long spicule of the sponge Pirania. In the background and below the Hazelia meadow, a small Paterina specimen is barely visible from this distance.

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The tour ends with a close-up of Vauxia, a sponge with a distinct “cactus-like” branching pattern and fine reticulate meshwork of spicules.  Attached to one Vauxia branch by a long flexible stalk is Herpetogaster, a bizarre animal with a pair of long branching tentacles. Herpetogaster was a possible filter-feeder or a micropredator, using its flexible tentacles to capture small prey animals or food particles in the water column.

End of sequence.

Total length = 60 sec.