''Callianassa subterranea'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

burrowing An eastern chipmunk at the entrance of its burrow A burrow is a hole or tunnel excavated into the ground by an animal to construct a space suitable for habitation or temporary refuge, or as a byproduct of locomotion. Burrows provide a form of s ...

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 con ...

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

Description

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

carapace A carapace is a 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 tortoises, the unde ...

, and a short

rostrum Rostrum may refer to: * Any kind of a platform for a speaker: **dais **pulpit ** podium * Rostrum (anatomy), a beak, or anatomical structure resembling a beak, as in the mouthparts of many sucking insects * Rostrum (ship), a form of bow on naval ...

. Its pale, translucent

exoskeleton An exoskeleton () . is a skeleton that is on the exterior of an animal in the form of hardened integument, which both supports the body's shape and protects the internal organs, in contrast to an internal endoskeleton (e.g. human skeleton, that ...

is not heavily calcified and remains relatively soft and flexible. Its large

claw A claw is a curved, pointed appendage found at the end of a toe or finger in most amniotes (mammals, reptiles, birds). Some invertebrates such as beetles and spiders have somewhat similar fine, hooked structures at the end of the leg or Arthro ...

s 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 the former infraorder classification 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'' ...

decapods The Decapoda or decapods, from Ancient Greek δεκάς (''dekás''), meaning "ten", and πούς (''poús''), meaning "foot", is a large order (biology), order of crustaceans within the class Malacostraca, and includes crabs, lobsters, crayfis ...

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

sediment Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of ...

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

biofilm A biofilm is a Syntrophy, syntrophic Microbial consortium, community of microorganisms in which cell (biology), cells cell adhesion, stick to each other and often also to a surface. These adherent cells become embedded within a slimy ext ...

that sticks to them. To facilitate this type of

foraging Foraging is searching for wild food resources. It affects an animal's fitness because it plays an important role in an animal's ability to survive and reproduce. Foraging theory is a branch of behavioral ecology that studies the foraging behavi ...

, its mouthparts, except for the

mandible In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

, are covered with a variety of

seta In biology, setae (; seta ; ) are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Depending partly on their form and function, protostome setae may be called macrotrichia, chaetae, ...

e designed for sediment denitrification. Its

pereiopod The anatomy of a decapod consists of 20 body segments grouped into two main body parts: the cephalothorax and the pleon (abdomen). Each segment – often called a somite – may possess one pair of appendages, although in various groups these m ...

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

grooming A groom (short for bridegroom) is a male participant in a wedding ceremony. Groom or grooming may also refer to: Occupations * Groom (profession), a person responsible for the feeding and care of horses * One of the competitors in combined drivi ...

Range and habitat

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

Norway Norway, officially the Kingdom of Norway, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. The remote Arctic island of Jan Mayen and the archipelago of Svalbard also form part of the Kingdom of ...

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 east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern Eur ...

. It has been recorded in large numbers in the southern

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

and the north-eastern

Irish Sea The Irish Sea is a body of water that separates the islands of Ireland and Great Britain. It is linked to the Celtic Sea in the south by St George's Channel and to the Inner Seas off the West Coast of Scotland in the north by the North Ch ...

. Its presence has been recorded on the south coast of

Britain Britain most often refers to: * Great Britain, a large island comprising the countries of England, Scotland and Wales * The United Kingdom of Great Britain and Northern Ireland, a sovereign state in Europe comprising Great Britain and the north-eas ...

and the west coast of

Scotland Scotland is a Countries of the United Kingdom, country that is part of the United Kingdom. It contains nearly one-third of the United Kingdom's land area, consisting of the northern part of the island of Great Britain and more than 790 adjac ...

. In

Ireland Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...

it has been recorded at a single site in the

Kenmare River Kenmare River or Kenmare Bay ( or , 'the bay of Neidín') is a long and narrow bay in south-west Ireland. The bay is enclosed by the Iveragh Peninsula on the north side, and the Beara Peninsula on the south, with most of its shores belonging to C ...

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 (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

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. A 1903 paper in the '' American Journal of Psychology'' defined a "habit, from the standpoint of psychology, ...

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 the Ancient Greek word (), meaning "the depths". ...

habitat. ''C. subterranea'' creates complex, multi-branched tunnel systems up to 81 cm deep from the lower shore to the shallow

sublittoral The littoral zone, also called litoral or nearshore, is the part of a sea, lake, or river that is close to the shore. In coastal ecology, the littoral zone includes the intertidal zone extending from the high water mark (which is rarely in ...

. Each tunnel complex has several inhalant shafts which terminate on the surface with a

funnel A funnel is a tube or pipe that is wide at the top and narrow at the bottom, used for guiding liquid or powder into a small opening. Funnels are usually made of stainless steel, aluminium, glass, or plastic. The material used in its constructi ...

-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'', ''

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 ''Nephrops norvegicus'', known variously as the Norway lobster, Dublin Bay prawn, ' (compare langostino) or ''scampi'', is a slim, coral-colored lobster that grows up to long, and is "the most important commercial crustacean in Europe". It is ...

''. 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 a word meaning "lake" or "inlet, sea inlet" in Scottish Gaelic, Scottish and Irish Gaelic, subsequently borrowed into English. In Irish contexts, it often appears in the anglicized form "lough". A small loch is sometimes calle ...

s and other areas with fine-grained mud.

References

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