Sand bubbler crabs (or sand-bubblers) are

crab Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) ( el, βραχύς , translit=brachys = short, / = tail), usually hidden entirely under the thorax. They live in all the ...

s of the

genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

''Scopimera'' and ''Dotilla'' in the family

Dotillidae The Dotillidae are a family of crabs with 59 species, nearly half of which are in the genus '' Ilyoplax''. The two genera ''Scopimera'' and ''Dotilla'' are collectively the sand bubbler crab Sand bubbler crabs (or sand-bubblers) are crabs of ...

. They are small crabs that live on sandy beaches in the tropical

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

. They feed by filtering sand through their mouthparts, leaving behind balls of sand that are disintegrated by the incoming high tide.

Description

Sand bubbler crabs are small crabs, around across the

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 they are characterised by the presence of "gas windows" on the merus of the

legs A leg is a weight-bearing and locomotive anatomical structure, usually having a columnar shape. During locomotion, legs function as "extensible struts". The combination of movements at all joints can be modeled as a single, linear element ...

; in ''Dotilla'', these windows are also present on the

thoracic The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the crea ...

sternite The sternum (pl. "sterna") is the ventral portion of a segment of an arthropod thorax or abdomen. In insects, the sterna are usually single, large sclerites, and external. However, they can sometimes be divided in two or more, in which case the ...

s. A similar system has evolved in parallel in the porcelain crab genus ''

Petrolisthes ''Petrolisthes'' is a genus of marine porcelain crabs, containing these extant species: *'' Petrolisthes aegyptiacus'' Werding & Hiller, 2007 *'' Petrolisthes agassizii'' Faxon, 1893 *''Petrolisthes amoenus'' (Guérin-Méneville, 1855) *'' Petr ...

''.

Distribution

Sand bubbler crabs are widespread across the

region, where they occur abundantly on sandy beaches in the tropics and sub-tropics.

Ecology and behaviour

Sand bubbler crabs live in

burrow 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 sh ...

s in the sand, where they remain during high tide. When the tide is out, they emerge on to the surface of the sand, and pass the sand through their mouthparts, eating detritus and plankton, and discarding the processed sand as pellets, which cover the beach. The crabs work radially from the entrance to their burrows, which they re-enter as the tide rises and disintegrates the pellets. In each burrow, the crab waits out the high tide in a bubble of air. The material consumed by sand bubbler crabs has a very low concentration of organic matter, which is concentrated by egestion of indigestible material.

Taxonomy

Taxonomic history

The first sand bubbler crab to be described was ''Cancer sulcatus'' (now ''

Dotilla sulcata Sand bubbler crabs (or sand-bubblers) are crabs of the genera ''Scopimera'' and ''Dotilla'' in the family Dotillidae. They are small crabs that live on sandy beaches in the tropical Indo-Pacific. They feed by filtering sand through their mout ...

'') by Peter Forsskål in 1775. The genus ''Scopimera'' was originally described as a

subgenus In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...

of ''

Ocypode ''Ocypode'' is a genus of ghost crabs found in the sandy shores of tropical and subtropical regions throughout the world. They have a box-like body, thick and elongated eyestalks, and one claw is larger than the other in both males and female ...

'' by Wilhem de Haan in 1833, although the first species, ''Scopimera globosa'' was not validly described until 1835. At the same time, De Haan tried to erect the genus ''Doto'' for Forskål's ''Cancer sulcatus'', not realising that the name was

preoccupied The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linn ...

by the

mollusc Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...

genus '' Doto''. The first available name for that genus was published by

William Stimpson William Stimpson (February 14, 1832 – May 26, 1872) was a noted American scientist. He was interested particularly in marine biology. Stimpson became an important early contributor to the work of the Smithsonian Institution and later, direc ...

in 1858, who called it ''Dotilla''. Ongoing

revisions Revision is the process of revising. More specifically, it may refer to: * Update, a modification of software or a database * Revision control, the management of changes to sets of computer files * '' ReVisions'', a 2004 anthology of alternate h ...

are likely to split the current genus ''Scopimera'' into at least two genera.

Species

Eight species of ''Dotilla'' and fifteen of ''Scopimera'' are currently recognised: * ''Dotilla'' **'' Dotilla blanfordi'' Alcock, 1900 **'' Dotilla fenestrata'' Hilgendorf, 1869 **'' Dotilla intermedia'' De Man, 1888 **'' Dotilla malabarica'' Nobili, 1903 **'' Dotilla myctiroides'' (H. Milne-Edwards, 1852) **'' Dotilla pertinax'' Kemp, 1915 **''

'' (Forskål, 1775) **'' Dotilla wichmani'' De Man, 1892 *''Scopimera'' **'' Scopimera bitympana'' Shen, 1930 **'' Scopimera crabicauda'' Alcock, 1900 **'' Scopimera curtelsoma'' Shen, 1936 **''

Scopimera globosa Sand bubbler crabs (or sand-bubblers) are crabs of the genera ''Scopimera'' and ''Dotilla'' in the family Dotillidae. They are small crabs that live on sandy beaches in the tropical Indo-Pacific. They feed by filtering sand through their mouthpar ...

'' (De Haan, 1835) **'' Scopimera gordonae'' Serène & Moosa, 1981 **'' Scopimera inflata'' A. Milne-Edwards, 1873 **'' Scopimera intermedia'' Balss, 1934 **'' Scopimera investigatoris'' Alcock, 1900 **''

Scopimera kochi Sand bubbler crabs (or sand-bubblers) are crabs of the genera ''Scopimera'' and ''Dotilla'' in the family Dotillidae. They are small crabs that live on sandy beaches in the tropical Indo-Pacific. They feed by filtering sand through their mout ...

'' Roux, 1917 **'' Scopimera longidactyla'' Shen, 1932 **''

Scopimera philippinensis Sand bubbler crabs (or sand-bubblers) are crabs of the genera ''Scopimera'' and ''Dotilla'' in the family Dotillidae. They are small crabs that live on sandy beaches in the tropical Indo-Pacific. They feed by filtering sand through their mout ...

'' Wong, Shih & Chan, 2011 **'' Scopimera pilula'' Kemp, 1919 **'' Scopimera proxima'' Kemp, 1919 **'' Scopimera sheni'' Wong, Shih & Chan, 2011 **'' Scopimera sigillorum'' (Rathbun, 1914)

References

External links

* {{Taxonbar, from=Q1227769 Ocypodoidea Arthropod common names