''Ratabulus'' is a genus of

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

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 ...

ray-finned fish belonging to the family

Platycephalidae The Platycephalidae are a family of marine fish, most commonly referred to as flatheads. They are relatives of the popular lionfish, belonging to the order Scorpaeniformes. Taxonomy Platycephalidae was first proposed as a family in 1839 by the E ...

. These fishes are native to the eastern Indian Ocean and the western Pacific Ocean.

Taxonomy

''Ratabulus'' was first formally proposed as a monotypic genus in 1924 by the American ichthyologists

David Starr Jordan David Starr Jordan (January 19, 1851 – September 19, 1931) was the founding president of Stanford University, serving from 1891 to 1913. He was an ichthyologist during his research career. Prior to serving as president of Stanford Univer ...

and

Carl Leavitt Hubbs Carl Leavitt Hubbs (October 19, 1894 – June 30, 1979) was an American ichthyologist. Biography Youth He was born in Williams, Arizona. He was the son of Charles Leavitt and Elizabeth (née Goss) Hubbs. His father had a wide variety of jobs (f ...

with ''Thysanophrys megacephalus'', which had been described in 1917 by Shigeho Tanaka from a type specimen obtained at a fish market in Tokyo, designated as its type species. This genus is

classified Classified may refer to: General *Classified information, material that a government body deems to be sensitive *Classified advertising or "classifieds" Music *Classified (rapper) (born 1977), Canadian rapper *The Classified, a 1980s American roc ...

within the family Playtcephalidae, the flatheads which the 5th edition of ''

Fishes of the World ''Fishes of the World'' by the American ichthyologist Joseph S. Nelson (1937–2011) is a standard reference for fish systematics. Now in its fifth edition (2016), the work is a comprehensive overview of the diversity and classification of the ...

'' classifies within the

suborder Order ( la, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and ...

Platycephaloidei in the

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...

Scorpaeniformes.

Etymology

''Ratabulus'' did not have its etymology explained by Jordan and Hubbs, however, the name was also spelled as ''Rutabulus'' by them, likely to derive from ''rutabulum'', which is a Latin word meaning shovel, an allusion to the shovel-nosed head of ''R. megacephalus''.

Species

''Ratabulus'' contains 10 species:

Characteristics

''Ratabulus'' flatheads have two or more preopercular spines have at least 2 spines on the

preoperculum This glossary of ichthyology is a list of definitions of terms and concepts used in ichthyology, the study of fishes. A B C ...

, with the upper spine being the longest. There is no elongation of the upper lobe of the caudal fin with no elongated filament extending out from that fin. The first dorsal fin has between 8 or 9 spines. the second being equal in height to the third, while the second dorsal fin has no more than 12 soft rays. There are 2 separate patches of vomerine teeth. There are between 48 and 56 pored scales, each with 2 pores, on the

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...

with spines on the scales in the anterior portion of that line. The diagonal rows of scales run downwards and backwards over lateral line and the number of these rows is roughly about equal to the number of scales in the lateral line, typically with a difference of only 1 or 2 scales. The canine-like teeth in the jaws are depressible. There are 3 or more spines below the eye on a suborbital ridge and the lappet on the iris is pointed. The maximum length attained by these fishes varies from a

standard length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish m ...

of in ''R. humerosus'' to in ''R. diversidens''.

Distribution

''Ratabulus'' flatheads are found in the far east of the Indian Ocean and the western Pacific Ocean. One species, ''R. prionotus'', has moved through the

Suez Canal The Suez Canal ( arz, قَنَاةُ ٱلسُّوَيْسِ, ') is an artificial sea-level waterway in Egypt, connecting the Mediterranean Sea to the Red Sea through the Isthmus of Suez and dividing Africa and Asia. The long canal is a popular ...

to be recorded as a

Lessepsian migrant The Lessepsian migration (also called Erythrean invasion) is the migration of marine species across the Suez Canal, usually from the Red Sea to the Mediterranean Sea, and more rarely in the opposite direction. When the canal was completed in 18 ...

in the eastern Mediterranean Sea.

References

{{Taxonbar, from=Q2796409 Platycephalidae Marine fish genera Taxa named by David Starr Jordan Taxa named by Carl Leavitt Hubbs