Gastropods (Snails)

Limpets covering the base of a hydrotherma vent

The most common type of marine snail (Phylum Mollusca, Class Gastropoda) at Axial is a Limpet, one of the primary organisms that inhabits the hydrothermal vent chimneys.  Another snail, the Glob Snail is also very common, though considerably smaller and more difficult to see. 

Juan de Fuca Limpet (Lepetodrilus fucensis)

LimpetsLimpets are a group of marine snails, members of Class Gastropoda.  Lepetodrilus fucensis , often referred to as the Juan de Fuca Limpet is the common limpet found on Axial Seamount, and it is the most abundant macrofaunal organism found on Axial's hydrothermal vents.  However, due to their small size (~10 mm) these limpets rank third in terms of Axial's biomass. They are most abundant on sulfide chimneys, and are often attached to the abundant tube worms.  They are also found occasionally on basalt lava surfaces.
    This limpet species has multiple feeding strategies: grazing, suspension feeding, and obtaining organic material from endosymbiotic bacteria. It is common to see many specimens vertically stacked on one another, allowing them better ability to suspension feed.  This stacking characteristic makes them good competitors for space on a vent. They appear to have no major predator at Axial Seamount. 
Tunnicliffe, Verena, and Maia Tsurumi. "Tubeworm-associated communities at hydrothermal vents on the Juan de Fuca Ridge, northeast Pacific." Deep Sea Research Part I: Oceanographic Research Papers: 611-629.

Glob Snail (Depressigyra globulus)

Globe SnailThe second most dominant species of Gastropod at Axial Seamount is the Glob Snail. It is tiny with a brown high-spiral shell.  It is found living among the limpets and tube worms on hydrothermal vents.