Meet Hypselodoris Krakatoa, an ocean-dwelling nudibranch or sea slug whose gills resemble an erupting tropical volcano.  

Krakatoa Inspired The Name Of This 'Volcanic' Sea Slug

Krakatoa is in the news again, and as usual it's for all the wrong reasons. To be fair, the original Krakatoa catastrophically blew itself to smithereens in 1883 – those who watched The Time Tunnel on TV back in 1966 know the story well.

The current troublemaker is Anak Krakatoa (“Son of Krakatoa”), a successor volcano that first rose above the waves in 1930 and has been growing at a rate of roughly 22 feet per year since the 1950s. Father, son, whatever – Krakatoa is pretty much the poster child for volcanoes and as such, it's no wonder Hypselodoris Krakatoa was named for the fire-breathing fumarole.   

Krakatoa Inspired The Name Of This 'Volcanic' Sea Slug

Hypselodoris Krakatoa was described and named relatively recently – in 1999 to be exact – by T.M. Gosliner and R.F. Johnson, whose work appeared in the Zoological Journal of the Linnean Society. The creature is a nudibranch or sea slug measuring roughly 55mm (about 2 inches) in length.

It's native to parts of the western Pacific Ocean ranging from near Japan in the north to the warm waters off Papua New Guinea. Thus, it wouldn't be unusual to find specimens near Krakatoa, west of Java. Yes, west: believe the map, not the movie!

Krakatoa Inspired The Name Of This 'Volcanic' Sea Slug

As mentioned, Hypselodoris Krakatoa was named for its “volcanic-looking” gill pocket. This anatomical structure consists of a peak-like mound on the sea creature's dorsal (back) side. Extending upwards from the tip of the gill pocket are the feathery gills themselves, arranged as an expanding fan that superficially resembles an ash cloud spewed from a volcanic eruption.

Volcanic or not, Hypselodoris Krakatoa would be wise to wander anywhere BUT the waters around Anak Krakatoa. Not only is the region regularly rained upon by ash from the ongoing eruptions, a series of recent undersea landslides are thought to have spawned a tsunami that brought devastation, injuries and fatalities to areas nearby. Definitely no place for Man, beast, or slug. (images via {1} Rickard Zerpe and {2}, {3} Jayvee Fernandez)