Creature 236: Riftia pachyptila

An animal which can't eat

Riftia pachyptila is commonly known as a giant tube worm.

These worms can grow up to two and a half meters long, but several parts of their morphology have been highly modified or reduced to vestigial. Instead of a mouth and digestive system Riftia pachyptila relies on a symbiotic relationship with various microbes. The red tip is a feather-like structure called a plume. It is similar to some gills, except it is used to provide more than just Oxygen, it absorbs various dissolved gases which the microbes need to grow and reproduce. In return the microbes provide the nutrients which the giant tube worm needs to survive. As a result of this the giant tube worm is highly tolerant to certain chemicals such as Hydrogen Sulfide, which its dependent bacteria can metabolize. The plume can be retracted back into a hardened tube for protection.

Distribution:
Riftia pachyptila are found living near hydrothermal vents in the Pacific ocean.

Classification:
Riftia pachyptila is in the same phylum as Earthworms.
Kingdom: Animalia
Phylum: Annelida
Class: Polychaeta
Order: Canalipalpata
Family: Siboglinidae
Genus: Riftia
Species: Riftia pachyptila

Image Links:
http://en.wikipedia.org/wiki/Giant_tube_worm
http://bioweb.uwlax.edu/bio203/s2007/rossing_jaco/introduction__the_worm_under_inv.htm

Creature 87: Sabellidae

A worm that looks like a feather duster

Description:
Sabellidae are a family of segmented worms which look a little something like this:

Those long feathery protrusions called branchiae are actually coming out of their head. Their purpose is to trap small particles of food which they eat. They also serve a respiratory function. Unlike most filter feeders Sabellid worms are remarkable fussy eaters and their branchiae are highly specialized for catching the right type of food. Sabellidae protect their body with tubes of hardened material like sand and bits of shells cemented together by Calcium Carbonate. They spend most of their time with only their head protruding. They can retract their head when they are threatened.

Distribution:
Sabellid are found in the inter-tidal zones all over the world but are more common in warm waters.

Classification:
Kingdom: Animalia
Phylum: Polychaeta
Class:
Order: Canalipalpata
Family: Sabellidae

Image Links:
http://www.redditian.com/r/WTF/28jpwm
http://en.wikipedia.org/wiki/Sabellidae#mediaviewer/File:Feather_duster_worm.jpg

Creature 34: Chaetopterus pugaporcinus

A worm that looks like a pig butt

Description:
Today we have another recently described (2007) bizarre creature from the ocean depths; Chaetopterus pugaporcinus. Chaetopterus pugaporcinus is commonly called the pigbutt worm or the flying buttocks and it does not take an overactive imagination to work out why:

This unusual looking animal is a segmented worm, just like earthworms or leeches. Two of the middle segments are inflated giving the pig butt worm the ability to float around deep in the pelagic zone of the ocean. The other segments form a sort of layering you can see around the middle. In their natural state they have been observed floating around in a cloud of their own mucous several times the size of their body. It is assumed that this is how the capture their food.
The creature is capable of bioluminescence and can be coaxed to emit a bright blue light:

They also emit bioluminescent spots in their mucous.

Distribution:
The Pigbutt worm is found lower in the Mesopelagic and in the Bathyalpelagic zones of the ocean. The original specimens were found in off Monterey Bay, California but it is unlikely that they are restricted to the area.

Classification:
Kingdom: Animalia
Phylum: Annelida
Class: Polychaeta
Order: Canalipalpata
Family: Chaetopteridae
Genus: Chaetopterus
Species Chaetopterus pugaporcinus


Image Links:
http://www.wired.com/2013/10/strange-deep-sea-creatures/#slideid-592111
http://www.biolbull.org/content/212/1/40.full