''Callianassa subterranea'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of burrowing ghost shrimp. This species is known by such generic

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...

s as "mud shrimp" and "ghost shrimp".

Description

''Callianassa subterranea'' has an elongated body, a short small

carapace A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...

, and a short rostrum. Its pale, translucent

exoskeleton An exoskeleton (from Greek ''éxō'' "outer" and ''skeletós'' "skeleton") is an external skeleton that supports and protects an animal's body, in contrast to an internal skeleton (endoskeleton) in for example, a human. In usage, some of the ...

is not heavily calcified and remains relatively soft and flexible. Its large claws are unequal in size and are larger in males than in females. ''C. subterranea'' has very small eyes and grows up to in length. Like many similar

thalassinidea Thalassinidea is a former infraorder of decapod crustaceans that live in burrows in muddy bottoms of the world's oceans. In Australian English, the littoral thalassinidean ''Trypaea australiensis'' is referred to as the ''yabby'' (a term which al ...

n decapods, ''C. subterranea'' is a deposit-feeder that ingests

sediment Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand an ...

particles in order to scrape off and digest the organic coating called

biofilm A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular ...

that sticks to them. To facilitate this type of foraging, its

mouthparts Mouthparts may refer to: * The parts of a mouth ** Arthropod mouthparts *** Insect mouthparts {{disambig ...

, except for the

mandible In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower tooth, teeth in place. The mandible sits beneath the maxilla. It is the only movabl ...

, are covered with a variety of

seta In biology, setae (singular seta ; from the Latin word for "bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. Th ...

e designed for sediment denitrification. Its

pereiopod The decapod (crustaceans such as a crab, lobster, shrimp or prawn) is made up of 20 body segments grouped into two main body parts: the cephalothorax and the pleon (abdomen). Each segment may possess one pair of appendages, although in various g ...

s are highly specialized for the digging activity of a deposit feeder and are not used for grooming.

Range and habitat

''C. subterranea'' has a widespread marine distribution from

Norway Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and t ...

to the

Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ea ...

. It has been recorded in large numbers in the southern

North Sea The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian S ...

and the north-eastern

Irish Sea The Irish Sea or , gv, Y Keayn Yernagh, sco, Erse Sie, gd, Muir Èireann , Ulster-Scots: ''Airish Sea'', cy, Môr Iwerddon . is an extensive body of water that separates the islands of Ireland and Great Britain. It is linked to the Ce ...

. Its presence has been recorded on the south coast of Britain and the west coast of

Scotland Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to the ...

. In

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

it has been recorded at a single site in the

Kenmare River Kenmare () is a small town in the south of County Kerry, Ireland. The name Kenmare is the Anglicisation, anglicised form of ''Ceann Mara'', meaning "head of the sea", referring to the head of Kenmare Bay. Location Kenmare is located at the hea ...

area. However, as it is a subterranean species, it likely has a more widespread range that has been recorded. As its

scientific name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

implies, this species has a burrowing

habit A habit (or wont as a humorous and formal term) is a routine of behavior that is repeated regularly and tends to occur subconsciously.

and lives underneath the wet, sandy sediment of its

benthic zone The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning " ...

habitat. ''C. subterranea'' creates complex, multi-branched tunnel systems up to 81 cm deep from the lower shore to the shallow sublittoral. Each tunnel complex has several inhalant shafts which terminate on the surface with a funnel-shaped opening in the center of a conical mound of ejected sediment. Its burrows often interconnect in complex patterns with those inhabited by other species of burrowing fish and crabs such as ''

Goneplax rhomboides ''Goneplax rhomboides'' is a species of crab. It is known by the common name angular crab because of its angular carapace. Although it is also called the ''square crab'', its shell is in fact more trapezoidal than square (or rhomboidal, as its sc ...

'', ''

Cepola macrophthalma ''Cepola macrophthalma'' is a species of marine ray-finned fish belonging to the family Cepolidae, the bandfishes. It is found in the eastern Atlantic and Mediterranean from Senegal north to the British Isles. This species is known as the red ba ...

'', '' Lesueurigobius friesii'', and '' Nephrops norvegicus''. The construction of the burrows varies according to the characteristics of the sediment in which the individuals dwell and reach their maximum depth and complexity in Scottish

sea loch ''Loch'' () is the Scottish Gaelic, Scots and Irish word for a lake or sea inlet. It is cognate with the Manx lough, Cornish logh, and one of the Welsh words for lake, llwch. In English English and Hiberno-English, the anglicised spelling ...

s and other areas with fine-grained mud.

References

{{Taxonbar, from=Q5021928 Thalassinidea Crustaceans of the Atlantic Ocean Crustaceans described in 1808