Doras is a small genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of catfish

Catfish

Catfishes are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the heaviest and longest, the Mekong giant catfish from Southeast Asia and the second longest, the wels catfish of Eurasia, to detritivores...

es (order

Order (biology)

In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 Siluriformes) of the family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Doradidae

Doradidae

Doradidae is a family of catfishes also known as thorny catfishes or talking catfishes. These fish are native to South America, primarily in Brazil, Peru, and the Guianas.Doradids are omnivorous.-Taxonomy:...

. This genus contains two extant species, D. carinatus and D. micropoeus.

Distribution

Doras species are distributed in South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

. D. carinatus inhabits the Essequibo River

Essequibo River

The Esequibo River is the largest river in Guyana, and the largest river between the Orinoco and Amazon. Rising in the Acarai Mountains near the Brazil-Guyana border, the Essequibo flows to the north for 1,010 km through forest and savanna into the Atlantic Ocean.-Geography:There are countless...

 basin and other coastal drainages east to the mouth of the Amazon River

Amazon River

The Amazon of South America is the second longest river in the world and by far the largest by waterflow with an average discharge greater than the next seven largest rivers combined...

, and is possibly in lower Amazon and lower Orinoco River basins. D. micropoeus is found in the Essequibo, Demerara

Demerara River

The Demerara River is a river in eastern Guyana that rises in the central rainforests of the country and flows to the north for 346 kilometres until it reaches the Atlantic Ocean. Georgetown, Guyana's largest seaport and capital, is situated on the east bank of the river's mouth. The Demerara's...

 and Courantyne River

Courantyne River

The Corentyne / Courantyne / Corantijn River is a river in northern South America in the country of Suriname, it is the longest river in the state. The river originates in the Acarai Mountains and flows northward for approximately between Guyana and Suriname, emptying into the Atlantic Ocean near...

 basins and possibly other coastal drainages east to mouth of Amazon River.

Description

D. carinatus grows to a length of 30 centimetres (12 in) SL

Fish measurement

Fish measurement refers to the measuring of the length of individual fish and of various parts of their anatomy. These data are used in many areas of ichthyology, including taxonomy and fisheries biology.-Overall length:...

. D. micropoeus reaches a maximum size of 35 cm (14 in) SL.

D. carinatus can emit sounds by moving its pectoral spines. Every basic unit of sound emitted lasts for 60–70 millisecond

Millisecond

A millisecond is a thousandth of a second.10 milliseconds are called a centisecond....

s, with a frequency

Frequency

Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...

 of 60–90 hertz

Hertz

The hertz is the SI unit of frequency defined as the number of cycles per second of a periodic phenomenon. One of its most common uses is the description of the sine wave, particularly those used in radio and audio applications....

 corresponding to the reply frequency of the muscle

Muscle

Muscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...

s utilized.