Creature 296: Lybia edmondsoni

Is it a cheerleader or a boxer?
Lybia edmondsoni is a crab which can either be called the pom pom crab or the boxer crab.

The confusion over its identity as a cheerleader or a boxer comes from the fact that it likes to pick up sea anemones in its claws. These can resemble pom poms, but the stinging cells on the anemones can come in very handy when warding off predators.

Without this unusual defensive strategy they would be pretty vulnerable as they have a much softer carapace than most crabs.

Distribution:
Lybia edmondsoni is endemic to the Hawaiian island chain.

Classification:
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda
Family: Xanthidae
Genus: Lybia
Species: Lybia edmondsoni

Image Links:

https://en.wikipedia.org/wiki/Lybia_edmondsoni

https://www.pinterest.com/pin/262686590737924542/

Creature 239: Cymothoa exigua

A crustacean which becomes a tongue

Description:
Cymothoa exigua is an isopod crustacean, which is sometimes called the tongue eating louse.

Some of my regular readers may remember Macrocheles rettenmeyeri, the parasitic mite which replaces the foot of other arthropods. In a similar way this parasitic isopod eats and then replaces the tongue of fish. They enter the fish through the gills and then eat the tongue off. They latch on to where the tongue was and then live off the blood of the fish they have latched on to.

The first member of the species to enter the fish will mature into a male. When a second parasite infects the same fish the first on then becomes female.

Distribution:
Cymothoa exigua is found in tropical waters near coastal areas of the Eastern Pacific Ocean.

Classification:
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Isopoda
Family: Cymothoidae
Genus: Cymothoa 
Species: Cymothoa exigua 

Image Links:
http://www.buzzfeed.com/awesomer/there-is-a-parasite-that-eats-tongues-and-replaces-them-with#.grJbQ0w4D1
http://animalus.blog.pl/2013/12/30/cymothoa-exigua/

Creature 225: Dinochelus ausubeli

A mean looking claw

Dinochelus ausubeli is a recently discovered (2007) lobster which is sometimes called the terrible claw lobster.

It has several long, narrow tooth-like spikes on the inside of margin of their claws.  The right claw is grossly elongated and is several times larger than the left claw. We don't know what they use this freaky looking claw for.

Distribution:

The terrible claw lobster was found off the Phillipine Island of Luzon at a depth of about 250 m.

Classification:
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda
Family: Nephropidae
Genus: Dinochelus
Species: Dinochelus ausubeli

Image links:

https://www.tumblr.com/search/dinochelus%20ausubeli

Creature 93: Macrocheira kaempferi

This Crab has arms the length of a person

Happy New Year.

Description:
Another oversized animal today, this time it is a deep sea crustacean Macrocheira kaempferi commonly known as the Japanese spider crab.

Their body size may be only around 40 cm long, but the length of their claws from tip to tip can be up to 3.8 m long in males. This gives it the longest leg span of any arthropod. Females have much shorter limbs. Japanese spider crabs can weigh up to 19kg. The Japanese spider crab can live up to 100 years old.

I took this photo of a specimen from the Bernice P. Bishop Museum in Hawaii.

Distribution:
The Japanese Spider crab is found off the coast of the Japanese islands, most commonly off the coast of Honshu. The Japanese Spider crab usually lives at depths of around 150-300 m. During breeding season they migrate up to depths of around 50 m and the freshly hatched nauplius live as plankton near the surface of the ocean. They migrate to the ocean depths when they reach adulthood.

Classification:
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda
Family: Inachidae
Genus: Macrocheira
Species: Macrocheira kaempferi

Image Links:
http://en.wikipedia.org/wiki/Japanese_spider_crab#mediaviewer/File:Macrocheira_kaempferi.jpg

Creature 51: Bathynomus

Not your garden variety slater

Description:
I'm sure you've all see those little arthropods, in pretty much every garden in the world, which roll up into a hard ball when you pick them up. They go by many common names including slaters, rolly pollies, pillbugs and woodlice. Many people don't realize they are actually an order of crustaceans called isopoda and the majority of them live in the ocean. Bathynomus is a genus of about 20 of these marine isopods. They live in the deep ocean,  and like many species down there they have undergone deep sea gigantism.

Yes they can grow up to 76 cm long and weigh up to 1.7kg. They do have the ability to roll themselves up into balls when threatened, albeit very slowly.  They don't eat very often due to the fact that they are very rarely fully active metabolically. Most will only eat a few time per year with some individuals recorded spending years at a time without eating. When they do eat they eat so much that they can scarcely move afterwards. They are predominantly scavengers and feed off dead organisms that fall from the pelagic zone.

Distribution:
Bathynomus are benthic organisms usually found between 200 and 2000 meters in depth  and are found in all the major oceans of the world.

Classification:
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Isopoda
Suborder: Cymothoida
Family: Cirolanidae
Genus: Bathynomus

Image Links:
http://commons.wikimedia.org/wiki/Category:Bathynomus_giganteus#mediaviewer/File:Giant_isopod.jpg
http://trawlerphotos.co.uk/gallery/data/634/medium/bathynomus-giganteus-sideview.jpg

Creature 40: Odontodactylus scyllarus

A cructecean with super powers

Description: Odontodactylus scyllarus is commonly known as a Peacock mantis shrimp or clown mantis shrimp, but it is not a Peacock, or a clown, or a mantis or even a shrimp.

 Not only is this a bizarre looking creature with its stalked eyes and it brightly coloured exoskeleton, but it is widely known for having the fastest punch in the animal kingdom. Some fisherman have been known to call them thumb splitters because of what they do to your thumb. The Peacock clown mantis shrimp can punch at over 80km/h (50mph) with an acceleration of over 10,000 g, the action is so fast that it literally boils the water in a small area which creates a minute vacuum for an instant. The heat and light created when this vacuum implodes is large enough to be measured.

The Clown mantis shrimp moves its eyes around on its stalks roughly ever 300ms. The eyes are moves independently and in independent directions. As far as we can tell these movements are random (within certain parameters) and are made up of three independent unpredictable components: a tilt in the angle of the eye stalk axis, a vertical-horizontal tilt and a rotational component.

Distribution:

The Clown Mantis shrimp is very widespread occurring in shallow (3-40m) benthic ecosystems throughout the Indo-Pacific region.

Classification:
If you are wondering how these guys got their eclectic common name here is the explanation: Order Stromatpoda is commonly called the mantis shrimps in order to differentiate them from other shrimp like Orders. The peacock or clown at the front is a reference to the particular species.

Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Stomatopoda
Family: Odontodactylidae
Genus: Odontodactylus
Species: Odontodactylus scyllarus

Image Links:
http://commons.wikimedia.org/wiki/File:Odontodactylus_scyllarus1.jpg
http://upload.wikimedia.org/wikipedia/commons/3/39/OdontodactylusScyllarus2.jpg

Creature 32: Kiwa

A crustacean that grows its food on its own body

Description:

Kiwa hirsuta, commonly called  the Yeti crab or the furry lobster, is a recently (2005) discovered deep ocean crab which lives in Antarctic hydrothermal vents. They are usually lack pigment over their body and in their eyes which are greatly reduced to the extent that it seems that they may be completely blind. These are common adaptation in stygofauna rather than in deep ocean animals. They get their common name from the long fine setae which densely cover their underside and their legs.

Kiwa hirsuta

A second species, K. puravida was described in 2011, this time found in hydrothermal vents off the coast of Costa Rica. Both species feed off the bacteria that derive their energy from the heat around the hydrothermal vents. The thermophilic bacteria will be discussed in later posts. The using their long setae to trap them as they are taken with the currents. Their long fine setae capture the bacteria and provide an environment in which bacteria colonies can thrive. The yeti crabs then harvest these colonies for food.

Kiwa puravida

They tend to gather in swarms around the bacteria rich areas close to the opening of the hydrothermal vents.

Kiwa colony

The hydrothermal vents they occupy provide similar water temperatures to tropical water which is interesting because tropical water crabs often possess very hairy undersides. 

Distribution:

The Kiwa is only known from the hydrothermal vents on the Pacific Antarctic ridge and off the coast of Costa Rica, however there has been very reasonable speculation that there may be more species inhabiting hydrothermal vents of the deep ocean across the globe.

Classification:

The yeti crabs have their own family and technically speaking are neither a crab nor a lobster. They are in the Decapod order, a group which included the crabs, lobsters, hermit crabs, shrimp etc...  

Also note here that the class Malacostraca is used instead of the old class Crustecea because recent phylogenetic analyses have suggested that the class Crustecea is paraphyletic or possibly polyphyletic. This last point is aimed more at the botanists, Herpetologists and Ornithologists who refuse to give up on classifications which they know are archaic.

Kingdom: Animalia

Phylum: Arthropoda

Class: Malacostraca

Order: Decapoda

Family: Kiwaidae

Genus: Kiwa

Image Links:
http://en.wikipedia.org/wiki/Kiwa_hirsuta#mediaviewer/File:Fish14_yati_crap.jpg

http://www.nature.com/news/yeti-crab-grows-its-own-food-1.9537

http://en.wikipedia.org/wiki/Kiwaidae#mediaviewer/File:Dense_mass_of_anomuran_crab_Kiwa_around_deep-sea_hydrothermal_vent.jpg