The arrow goby (''Clevelandia ios'') 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), ...

goby The Gobioidei are a suborder of percomorph fish. Many of these fishes are called gobies. It is by far the largest and most diverse order within the order Gobiiformes, and one of the most diverse groups of ray-finned fish in general. The subord ...

native to marine and

brackish Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuari ...

waters of the

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the cont ...

coast of

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

from

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ...

. This species grows to a length of SL, though most do not exceed TL. This fish can also be found displayed in public aquaria. This species is the only known member of its

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

Description

The arrow goby is a small, pale grey,

translucent In the field of optics, transparency (also called pellucidity or diaphaneity) is the physical property of allowing light to pass through the material without appreciable light scattering by particles, scattering of light. On a macroscopic scale ...

fish which grows to in length. It has two

dorsal fin A dorsal fin is a fin on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

s; the first is the shorter and has 4-5 spines while the dorsal fin has 15-17 soft fin rays. The

anal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...

is about equal in length to the second dorsal fin and has 14-17 fin rays. Like other gobies, the

caudal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported only ...

is rounded and the

pectoral fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish aquatic locomotion, swim. Apart from the tail or caudal fin, fish fins have no direct connection with the vertebral column ...

s form a cone which the goby uses to prop the anterior part of its body above the substrate. Its scales are minute, and the mouth extends beyond to the eye. The dorsal fins have short horizontal stripes and the body is pale brownish-grey in colour with darker mottling.

Distribution

Arrow gobies are found along the Pacific Coast of North America, from the

Rivers Inlet Rivers Inlet is a fjord in the Central Coast region of the Canadian province of British Columbia, its entrance off Fitz Hugh Sound, about southwest of the community of Bella Coola and about north of the northern tip of Vancouver Island and th ...

in British Columbia to

Habitat and biology

The arrow goby occurs in sand or mud substrates, where it uses burrows created by

invertebrate Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate s ...

s as shelters when it is threatened and as a refuge at low tide. Some of the species which make burrows used by arrow gobies include the shrimps '' Neotrypaea californiensis'' and '' Upogebia pugettensis'' and the fat innkeeper worm ''

Urechis caupo ''Urechis caupo'' is a species of Echiura, spoon worm in the family Urechidae, commonly known as the innkeeper echiuran, the fat innkeeper worm (because their tunnels often contain other animals), the innkeeper worm, or the penis fish. It is fou ...

''. It is a common species of estuaries, lagoons and tidal sloughs, and it has been reported in freshwater. The adults feed on

diatom A diatom (Neo-Latin ''diatoma'') is any member of a large group comprising several Genus, genera of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of Earth's B ...

green algae The green algae (: green alga) are a group of chlorophyll-containing autotrophic eukaryotes consisting of the phylum Prasinodermophyta and its unnamed sister group that contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ...

tintinnid Tintinnids are ciliates of the choreotrich order Tintinnida, the name deriving from a Latin source meaning a small tinkling bell. They are distinguished by vase-shaped shells called '' loricae'', which are mostly protein but may incorporate min ...

s, and the eggs and young of the host shrimp or prawn. This species will place large food items close to crabs so that the crab will tear it into smaller pieces. Arrow gobies are prey for ''

Sebastes ''Sebastes'' is a genus of marine ray-finned fish belonging to the subfamily Sebastinae part of the family Scorpaenidae, most of which have the common name of rockfish. A few are called ocean perch, sea perch or redfish instead. They are found ...

'', staghorn sculpin, whitespot greenling and

tern Terns are seabirds in the family Laridae, subfamily Sterninae, that have a worldwide distribution and are normally found near the sea, rivers, or wetlands. Terns are treated in eleven genera in a subgroup of the family Laridae, which also ...

s. This species does not build a nest or provide any care for its offspring, and the eggs are dispersed into the water column. The underside of this goby is silvery, and when threatened, they use this to make a brief signal to other gobies before quickly taking refuge in the burrow. This is also used to signal for mates. The individuals of this species are

protogynous hermaphrodite Sequential hermaphroditism (called dichogamy in botany) is one of the two types of hermaphroditism, the other type being simultaneous hermaphroditism. It occurs when the organism's sex changes at some point in its life. A sequential hermaphrodite ...

s; young adults are females and as they mature they become male.

Etymology

The generic name ''Clevelandia'' honours the lawyer Daniel Cleveland (1838–1929), who was a founder and president of the San Diego Natural History Society and who made significant contributions to the knowledge of the flora and fauna of

southern California Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural List of regions of California, region that generally comprises the southern portion of the U.S. state of California. Its densely populated coastal reg ...

. Over a dozen plants – including the Cleveland sage and another genus '' Clevelandia'' – were also named after him. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

''ios'' is an Ancient Greek word for an arrow: . It refers to the slender fish's long body that is reminiscent of an arrow.

References

{{Taxonbar, from=Q2657665 Gobionellinae Fish described in 1882 Taxa named by David Starr Jordan Taxa named by Charles Henry Gilbert