Heteroconger

Heteroconger
Spotted garden eel, Heteroconger hassi
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Anguilliformes
Family:	Congridae
Subfamily:	Heterocongrinae
Genus:	Heteroconger Bleeker, 1868
Species
See text.

Heteroconger is a genus of marine congrid eels. These small, slender garden eels live in groups where each individual has its own burrow. Usually only the head and frontal half of the body is visible, but if disturbed they retreat entirely into their burrow. The greatest species richness is in the Indo-Pacific, but there are also species in the warmer parts of the Atlantic (including the Caribbean) and the eastern Pacific Its name relates to how a huge colony of the eels looks swaying in the current.

The garden eel is roughly 16 inches long, but very skinny. The eel has large eyes compared to its body, and a weak sense of smell because of its tiny nostrils. It is timid around other animals and people, but slightly aggressive towards other males of its species. If it feels threatened, it retreats into its burrow and closes it with a mucus block so the predator cannot dig into its home. It has a gland in its tail that secretes a sticky substance that keeps the burrow from falling in on itself and burying the garden eel in sand. Scientists have yet to figure out the garden eels lifespan in the wild.

The garden eel is a carnivore, and eats plankton. Because of the garden eel's large eyes it relies mostly on sight to find its food. It catches the plankton by staying in its burrow and swaying its head about to catch the plankton drifting by in the current.

Garden eels are sexual reproducers and sexually dimorphic. When mating season comes the eels move their burrows closer together, until they are within reaching distance. Then the male picks which female he wants to mate with and defends her viciously, biting at the head and even the eyes of any other suitors. The couple mates and the female releases the fertilized eggs, letting them float away and gather around the epipelagic zone. The garden eels develop and hatch out of their eggs while floating in the water and, when they are large enough, swim down to a sand bed and dig a burrow of their own.

One of its top predators, the Pacific snake eel, or Ophicthus triserialis, burrows into the sand near a colony, then digs under a garden eel’s burrow and grabs its tail. This all happens underground, where the unsuspecting garden eel can’t see what’s happening. Trigger fish scare the garden eels into retreating into their burrows, then dig them up and devour them.

Species

There are currently 21 recognized species in this genus:^[1]

• Heteroconger balteatus Castle & J. E. Randall, 1999
• Heteroconger camelopardalis (Lubbock, 1980)
• Heteroconger canabus (G. I. McT. Cowan & Rosenblatt, 1974) (White-ring garden eel)
• Heteroconger chapmani (Herre, 1923)
• Heteroconger cobra J. E. Böhlke & J. E. Randall, 1981 (Cobra garden eel)
• Heteroconger congroides (D'Ancona, 1928)
• Heteroconger digueti (Pellegrin, 1923) (Pale green eel)
• Heteroconger enigmaticus Castle & J. E. Randall, 1999
• Heteroconger hassi (Klausewitz & Eibl-Eibesfeldt, 1959) (Spotted garden eel)
• Heteroconger klausewitzi (Eibl-Eibesfeldt & Köster, 1983) (Galapagos garden eel)
• Heteroconger lentiginosus J. E. Böhlke & J. E. Randall, 1981 (Masked garden eel)
• Heteroconger longissimus Günther, 1870 (Brown garden eel)
• Heteroconger luteolus D. G. Smith, 1989 (Yellow garden eel)
• Heteroconger mercyae G. R. Allen & Erdmann, 2009
• Heteroconger obscurus (Klausewitz & Eibl-Eibesfeldt, 1959)
• Heteroconger pellegrini Castle, 1999 (Speckled garden eel)
• Heteroconger perissodon J. E. Böhlke & J. E. Randall, 1981
• Heteroconger polyzona Bleeker, 1868
• Heteroconger taylori Castle & J. E. Randall, 1995
• Heteroconger tomberua Castle & J. E. Randall, 1999
• Heteroconger tricia Castle & J. E. Randall, 1999

References

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