Thaumeledone gunteri is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of small, benthic

Benthos

Benthos is the community of organisms which live on, in, or near the seabed, also known as the benthic zone. This community lives in or near marine sedimentary environments, from tidal pools along the foreshore, out to the continental shelf, and then down to the abyssal depths.Many organisms...

, deep-sea octopus

Octopus

The octopus is a cephalopod mollusc of the order Octopoda. Octopuses have two eyes and four pairs of arms, and like other cephalopods they are bilaterally symmetric. An octopus has a hard beak, with its mouth at the center point of the arms...

 found in the bathyal zone

Bathyal zone

The bathyal zone or bathypelagic – from Greek βαθύς , deep – is that part of the pelagic zone that extends from a depth of 1000 to 4000 metres below the ocean surface. It lies between the mesopelagic above, and the abyssopelagic below. The average temperature hovers at about 39°F...

 in the Southern Ocean

Southern Ocean

The Southern Ocean comprises the southernmost waters of the World Ocean, generally taken to be south of 60°S latitude and encircling Antarctica. It is usually regarded as the fourth-largest of the five principal oceanic divisions...

 near South Georgia.

Description

The mantle

Mantle (mollusc)

The mantle is a significant part of the anatomy of molluscs: it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself.In many, but by no means all, species of molluscs, the epidermis of the mantle secretes...

 length of Thaumeledone gunteri is typically about 5cm (2in) and the total length 10cm (4in), the arms being relatively short at 5cm (2in). The background colour is whitish but the dorsal and ventral surfaces are covered by large, irregular, deep purple tubercle

Tubercle

A tubercle is generally a wart-like projection, but it has slightly different meaning depending on which family of plants or animals it is used to refer to....

s. The web that links the arms is uniformly pale. The head is narrower than the mantle and there are several large tubercles above the eye. The eight arms are joined by a deep web and there are about 35 small suckers on each arm. The funnel organ is "VV" shaped and there are 5 elements in the radula

Radula

The radula is an anatomical structure that is used by molluscs for feeding, sometimes compared rather inaccurately to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus...

. The posterior salivary gland

Salivary gland

The salivary glands in mammals are exocrine glands, glands with ducts, that produce saliva. They also secrete amylase, an enzyme that breaks down starch into maltose...

, a diagnostic feature in this genus, has a diameter of 11mm.

Phylogenetic relationships

The funnel organ in T. gunteri is similar to that in Thaumeledone peninsulae and they both share a characteristic loop in the rectum. Thaumeledone rotunda is a circumpolar species found at greater depths and has several morphological

Morphology (biology)

In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....

 features that are different from the other two species. Despite this, a phylogenetic

Phylogenetics

In biology, phylogenetics is the study of evolutionary relatedness among groups of organisms , which is discovered through molecular sequencing data and morphological data matrices...

 study undertaken in 2008 of the molecular relationships in the genus, determined that T. gunteri and T. rotunda are sister taxa

Taxon

|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...

 and that T. peninsulae is more distantly related.

Distribution

Thaumeledone gunteri is found in the far south Atlantic Ocean in an area around South Georgia including the Shag Rocks

Shag Rocks

Shag Rocks may refer to the following:* Shag Rocks * Shag Rocks, South Georgia* Shag Rocks * Shag Rocks...

, ranging from 53°S to 55°S and 39°W to 35°W. It has been caught by trawling

Trawling

Trawling is a method of fishing that involves pulling a fishing net through the water behind one or more boats. The net that is used for trawling is called a trawl....

at depths of 364-964m (1100-3000ft) but may well occur at greater depths as these waters are relatively under-explored.