''Evermannichthys bicolor'' (bicolored sponge goby) is a perciform

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 ...

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Gobiidae.Thacker, C. E. 2001 (19 Apr)
''Evermannichthys bicolor'', a new goby (Teleostei: Perciformes: Gobioidei) from Navassa Island
Contributions in Science (Los Angeles) No. 490: 1-5. As their name suggests, fishes in this species live inside sponges and can be found in the

Caribbean Sea The Caribbean Sea ( es, Mar Caribe; french: Mer des Caraïbes; ht, Lanmè Karayib; jam, Kiaribiyan Sii; nl, Caraïbische Zee; pap, Laman Karibe) is a sea of the Atlantic Ocean in the tropics of the Western Hemisphere. It is bounded by Mexico ...

. The size of their populations are unknown, meaning it is not currently clear whether the bicolored sponge goby is in need of conservation.

Description

Overall, the body of the bicolored sponge goby is elongate and thin. The scale-covering and the number pores on the head is reduced, and generally measures 2 mm dorso-ventrally.Patzner, R.A., J.L. Van Tassell, M. Kovačić and B.G. Kapoor, 2011. The biology of gobies. Enfield, NH : Science Publishers ; Boca Raton, FL : Distributed by CRC Press, 685 p. . Their color is dark across the dorsal-most third of their bodies, the lower two thirds are pale, and the fins are generally clear. The

frenum A frenulum (or frenum, plural: frenula or frena, from the Latin ''frēnulum'', "little bridle", the diminutive of ''frēnum'') is a small fold of tissue that secures the motion of a mobile organ in the body. In human anatomy Frenula on the hu ...

, which connects the upper lip to the snout is reduced in size, though the upper lip and snout are separated. The

tongue The tongue is a muscular organ (anatomy), organ in the mouth of a typical tetrapod. It manipulates food for mastication and swallowing as part of the digestive system, digestive process, and is the primary organ of taste. The tongue's upper surfa ...

has a notched edge.

Distribution and habitat

This species is

demersal The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer of ...

living between 27 and 30 m below the surface of tropical oceans. It can be found in the western

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

, especially near the

island An island (or isle) is an isolated piece of habitat that is surrounded by a dramatically different habitat, such as water. Very small islands such as emergent land features on atolls can be called islets, skerries, cays or keys. An island ...

Navassa Navassa Island (; ht, Lanavaz; french: l'île de la Navasse, sometimes ) is a small uninhabited island in the Caribbean Sea. Located northeast of Jamaica, south of Cuba, and west of Jérémie on the Tiburon Peninsula of Haiti, it is subject to ...

Jamaica Jamaica (; ) is an island country situated in the Caribbean Sea. Spanning in area, it is the third-largest island of the Greater Antilles and the Caribbean (after Cuba and Hispaniola). Jamaica lies about south of Cuba, and west of His ...

, and

Curaçao Curaçao ( ; ; pap, Kòrsou, ), officially the Country of Curaçao ( nl, Land Curaçao; pap, Pais Kòrsou), is a Lesser Antilles island country in the southern Caribbean Sea and the Dutch Caribbean region, about north of the Venezuela coast ...

Very little is known about the population numbers and conservation of this species, and it is considered

data deficient A data deficient (DD) species is one which has been categorized by the International Union for Conservation of Nature (IUCN) as offering insufficient information for a proper assessment of conservation status to be made. This does not necessaril ...

by the

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

Aplysina archeri (Stove-pipe Sponge-pink variation)

The bicolored sponge goby, as its name implies, lives inside

sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through t ...

s. Specifically, it lives deep within the sponge, near the openings of the in-current canals. The sponges provide protection for the bicolored sponge goby, as well as food, which is transported into the sponge via the in-current canals. It is thought that this species spends its entire life in sponges, and that its eggs either drift into a sponge from open water or are laid directly within a sponge.

Conservation

Bicolored sponge gobies are considered

by the

, meaning that estimations of the total number of individuals and the trend of the population through time is unknown. The species is not used by humans in any way, and no threats to them have been identified. While no specific actions have been taken to conserve this species, many portions of their native range (including their type locality) are protected areas.

References

External links

AQUATAB
{{Taxonbar, from=Q3290631 Gobiidae Fish described in 2001 Fish of the Caribbean Data deficient species