A flower-like benthic ctenophore with tentacles extended, attached to the leg of the LJ01A junction box at Slope Base (2900 meters depth). Credit: UW/NSF-OOI/WHOI; J2-1562, V23.

Close-up of a flower-like benthic ctenophore with tentacles extended, attached to the leg of the LJ01A junction box at Slope Base (2900 meters depth). Credit: UW/NSF-OOI/WHOI; J2-1562, V23.

Close-up of a grumpy-looking blob sculpin sitting on the seafloor at the International District vent field on Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1662, V24.

An inverted Aeginura jelly seen in the midwater near International District vent field on Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1662, V24.

A red Aeginura jelly seen in the midwater near International District vent field on Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1662, V24.

Close-up of a red Aeginura jelly seen in the midwater near International District vent field on Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1662, V24.

A deep-sea skate egg case (or mermaid's purse) sitting on the basalt rock seafloor at the International District vent field on Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1662, V24.

A red Aeginura jelly escaping the ROV near International District vent field on Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1662, V24.

Underside of a red Aeginura jelly near International District vent field on Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1662, V24.

A blob sculpin resting amid a clump of tube worms at the International District vent field on Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1663, V24.

A blob sculpin facing the camera at the International District vent field on Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1663, V24.

A coronate jelly (possibly Periphyllopsis sp.) seen near Dymond vent field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1668, V24.

A coronate jelly (possibly Periphyllopsis sp.) with one protruding tentacle seen near Dymond vent field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1668, V24.

A coronate jelly (possibly Periphyllopsis sp.) floating above Dymond vent field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1668, V24.

Close-up of a coronate jelly (possibly Periphyllopsis sp.) above Dymond vent field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1668, V24.

Credit: UW/NSF-OOI/WHOI; J2-1668, V24.

A pink enteropneust (aka Acorn Worm) at Dymond Vent Field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1668, V24.

Close-up of a pink enteropneust (aka Acorn Worm) at Dymond Vent Field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1668, V24.

An unknown species of eelpout pokes its head out of a crevice at Dymond Vent Field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1668, V24.

An unknown species of eelpout at Dymond Vent Field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1668, V24.

Credit: UW/NSF-OOI/WHOI; J2-1668, V24.

Credit: UW/NSF-OOI/WHOI; J2-1668, V24.

An unknown white crinoid seen at Dymond Vent Field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1669, V24.

A light purple, translucent sea cucumber crawling up a rock at Dymond Vent Field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1669, V24.

A white carnivorous sponge (possibly in the family Cladorhizidae), seen at Dymond Vent Field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1669, V24.

Unknown pink cucumber on a rock at Dymond Vent Field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1669, V24.

A spiky, light pink King crab (family Lithodidae) crawling on a rock face at the Dymond Vent Field on the SE flank of Axial Seamount. Credit: UW/NSF-OOI/WHOI; J2-1669, V24.