Osteichthyes

Source: Wikipedia, the free encyclopedia.

Osteichthyes
Temporal range:
Ma[1]
Example of Osteichthyes:
Queensland lungfish and West Indian Ocean coelacanth (two Sarcopterygii), iridescent shark and American black sturgeon (two Actinopterygii
)
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Clade: Eugnathostomata
Clade: Teleostomi
Superclass: Osteichthyes
Huxley, 1880
Classes

Osteichthyes (

semi-aquatic and terrestrial
vertebrates.

The group is divided into two main

lobe-finned fish (Sarcopterygii, which gave rise to all land vertebrates, i.e. tetrapods). The oldest known fossils of bony fish are about 425 million years old from the late Silurian,[1] which are also transitional fossils showing a tooth pattern that is in between the tooth rows of sharks and true bony fishes.[3] Despite the name, these early basal bony fish had not yet evolved ossification and their skeletons were still mostly cartilaginous, and the main distinguishing feature that set them apart from other fish clades were the development of foregut pouchs that eventually evolved into the swim bladders and lungs
, respectively.

Osteichthyes can be compared to

paraphyletic and include only fishes.[4] However, since 2013 widely cited ichthyology papers have been published with phylogenetic trees that treat the Osteichthyes as a clade including tetrapods.[5][6][7][4]

Characteristics

Late Silurian, 425 million years ago.[1] It has a combination of both ray-finned and lobe-finned
features.

Bony fish are characterized by a relatively stable pattern of

fissure
.

Early bony fish had simple

paired fins, which gave rise to tetrapods' limbs. They also evolved a pair of opercula (gill covers), which can actively draw water across the gills
so they can breathe without having to swim.

Bony fish do not have

placoid scales
like cartilaginous fish, instead they consist of three types of scales that do not penetrate the epidermis in the process. The three categories of scales for Osteichthyes which are cosmoid scales, ganoid scales, teleost scales. The teleost scales are also then divided into two subgroups which are the cycloid scales, and the ctenoid scales. All these scales have a base of bone that they all originate from, the only difference is that the teleost scales only have one layer of bone. Ganoid scales have lamellar bone, and vascular bone that lies on top of the lamellar bone, then enamel lies on top of both layers of bone. Cosmoid scales have the same two layers of bone that ganoid scales have expect they gave dentin in-between the enamel and vascular bone and lamellar (vascular and lamellar two subcategories for bone found in scales). All these scales are found underneath the epidermis and do not break the epidermis of the fish. Unlike the placoid scales that poke through the epidermis of the fish.

Classification

See also: Evolution of fish and List of prehistoric bony fish genera

...it is increasingly widely accepted that tetrapods, including ourselves, are simply modified bony fishes, and so we are comfortable with using the taxon Osteichthyes as a clade, which now includes all tetrapods...

Fishes of the World (5th ed) [4]

Traditionally, Osteichthyes was considered a

land vertebrates, as the common ancestor of all osteichthyans includes tetrapods
amongst its descendants. While the largest subclass, Actinopterygii (ray-finned fish), is monophyletic, with the inclusion of the smaller sub-class Sarcopterygii, Osteichthyes was regarded as paraphyletic.

This has led to the current cladistic classification which splits the Osteichthyes into two full classes. Under this scheme Osteichthyes is monophyletic, as it includes the tetrapods making it a synonym of the clade Euteleostomi. Most bony fish belong to the ray-finned fish (Actinopterygii).

Actinopterygii

ray-finned fish
freshwater and marine environments from the deep sea to the highest mountain streams. Extant species can range in size from Paedocypris, at 8 mm (0.3 in), to the massive ocean sunfish, at 2,300 kg (5,070 lb), and the long-bodied oarfish
, to at least 11 m (36 ft).
Sarcopterygii

lobe-finned fish
cladistic classification schemes, Sarcopterygii is a clade that includes the tetrapods. The living sarcopterygians are the coelacanths, lungfish, and the tetrapods. Early lobe-finned fishes had fleshy, lobed, paired fins, joined to the body by a single bone.[12] Their fins differ from those of all other fish in that each is borne on a fleshy, lobelike, scaly stalk extending from the body. Pectoral and pelvic fins have articulations resembling those of tetrapod limbs. These fins evolved into legs of the first tetrapod land vertebrates, amphibians. They also possess two dorsal fins with separate bases, as opposed to the single dorsal fin of actinopterygians (ray-finned fish). The braincase of sarcoptergygians primitively has a hinge line, but this is lost in tetrapods and lungfish. Many early lobe-finned fishes have a symmetrical tail. All lobe-finned fishes possess teeth covered with true enamel
.

Phylogeny

A phylogeny of living Osteichthyes, including the tetrapods, is shown in the

Whole-genome duplication took place in the ancestral Osteichthyes.[16]

Osteichthyes/
Euteleostomi

Biology

All bony fish possess

gills. For the majority this is their sole or main means of respiration. Lungfish and other osteichthyan species are capable of respiration through lungs or vascularized swim bladders. Other species can respire through their skin, intestines, and/or stomach.[17]

Osteichthyes are primitively

filter-feeder or detritivore
are documented.

Some bony fish are

sea horses
being notable in that the males undergo a form of "pregnancy", brooding eggs deposited in a ventral pouch by a female.

Examples

The ocean sunfish is one of the heaviest bony fish in the world.

The ocean sunfish is the heaviest bony fish in the world,[23] in late 2021, Portuguese fishermen found a dead sunfish near the coast of Faial Island, Azores, with a weight of 2,744 kilograms (6,049 lb) and 3.6 metres (12 ft) tall and 3.5 metres (11 ft) long established the biggest ocean sunfish ever captured.[24]

The longest is the

stout infantfish can measure less than 8 millimetres (0.31 in).[25][26]
The beluga sturgeon is the largest species of freshwater bony fish extant today, and Arapaima gigas is among the largest of the freshwater fish. The largest bony fish ever was Leedsichthys, which dwarfed the beluga sturgeon as well as the ocean sunfish, giant grouper and all the other giant bony fishes alive today.[27]

Comparison with cartilaginous fishes

Comparison of
cartilaginous and bony fishes [28]
Characteristic Sharks (cartilaginous) Bony fishes
Habitat Mainly marine Marine and freshwater
Shape Usually dorso-ventrally flattened Usually
bilaterally
flattened
Exoskeleton Separate dermal
placoid scales
 Overlapping dermal
ctenoid scales
Endoskeleton Cartilaginous Mostly bony
Caudal fin
Heterocercal
 Heterocercal or
diphycercal
Pelvic fins Usually posterior. Mostly anterior, occasionally posterior.
Intromittent organ Males use pelvic fins as claspers for transferring sperm to a female Do not use claspers, though some species use their
gonopodium
for the same purpose
Mouth Large, crescent shaped on the ventral side of the head Variable shape and size at the tip or terminal part of the head
Jaw suspension Hyostylic Hyostylic and autostylic
Gill openings Usually five pairs of gill slits which are not protected by an operculum. Five pairs of gill slits protected by an operculum (a lateral flap of skin).
Type of gills Larnellibranch with long interbranchial septum
Filiform
with reduced interbranchial septum
Spiracles The first gill slit usually becomes spiracles opening behind the eyes. No spiracles
Afferent branchial vessels Five pairs from
ventral aorta
to gills 		Only four pairs
Efferent branchial vessels Nine pairs Four pairs
Conus arteriosus
 Present in heart Absent
Cloaca A true cloaca is present only in cartilaginous fishes and
lobe-finned fishes
. 		In most bony fishes, the cloaca is absent, and the anus, urinary and genital apertures open separately [29]
Stomach Typically J-shaped Shape variable. Absent in some.
Intestine
 Short with spiral valve in lumen Long with no spiral valve
Rectal gland Present Absent
Liver Usually has two
lobes
 Usually has three lobes
Swim bladder Absent Usually present
Brain Has large olfactory lobes and cerebrum with small optic lobes and cerebellum Has small olfactory lobes and cerebrum and large optic lobes and cerebellum
Restiform bodies
 Present in brain Absent
Ductus endolymphaticus
 Opens on top of head Does not open to exterior
Retina Lacks cones Most fish have
double cones
, a pair of cone cells joined to each other.
Accommodation
of eye 		Accommodate for near vision by moving the lens closer to the retina Accommodate for distance vision by moving the lens further from the retina [30]
Ampullae of Lorenzini Present Absent
Male genital duct Connects to the anterior part of the genital kidney No connection to kidney
Oviducts Not connected to ovaries Connected to ovaries
Urinary and genital apertures United and
urinogenital apertures lead into common cloaca
 Separate and open independently to exterior
Eggs A small number of large eggs with plenty of yolk A large number of small eggs with little yolk
Fertilisation Internal Usually external
Development
Oviparous types develop externally using egg cases
 Normally develop externally without an egg case

See also

References

  1. ^
    S2CID 236438229
    .
  2. ^ Bony fishes Archived 2013-06-06 at the Wayback Machine SeaWorld. Retrieved 2 February 2013.
  3. ^ "Jaws, Teeth of Earliest Bony Fish Discovered". Archived from the original on November 14, 2007.
  4. ^
    ISBN 978-1-118-34233-6
    .
  5. ^
    PMID 23653398
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  6. doi:10.1186/s12862-017-0958-3
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  7. doi:10.1073/pnas.1719358115
    .
  8. ISBN 978-0-253-00537-3
    . Retrieved 12 May 2015.
  9. ISBN 978-0-520-94798-6
    . Retrieved 14 May 2015.
  10. ISBN 978-1-118-40764-6
    . Retrieved 22 May 2015.
  11. ISBN 978-0-03-910754-3
    .
  12. ^ Clack, J. A. (2002) Gaining Ground. Indiana University
  13. ^ Betancur-R; et al. (2013). "Complete tree classification (supplemental figure)" (PDF). PLOS Currents Tree of Life (Edition 1). Archived from the original (PDF) on 2013-10-21.
  14. ^ Betancur-R; et al. (2013). "Appendix 2 – Revised Classification for Bony Fishes" (PDF). PLOS Currents Tree of Life (Edition 1).
  15. PMID 28683774
    .
  16. PMID 16128622
    .
  17. ^ Helfman & Facey 1997.
  18. ^ Wegner, Nicholas C., Snodgrass, Owen E., Dewar, Heidi, John, Hyde R. Science. "Whole-body endothermy in a mesopelagic fish, the opah, Lampris guttatus". pp. 786–789. Retrieved May 14, 2015.
  19. ^ "Warm Blood Makes Opah an Agile Predator". Fisheries Resources Division of the Southwest Fisheries Science Center of the National Oceanic and Atmospheric Administration. May 12, 2015. Retrieved May 15, 2015. "New research by NOAA Fisheries has revealed the opah, or moonfish, as the first fully warm-blooded fish that circulates heated blood throughout its body..."
  20. ^ Fritsches, K.A., Brill, R.W., and Warrant, E.J. 2005. Warm Eyes Provide Superior Vision in Swordfishes. Archived 2006-07-09 at the Wayback Machine Current Biology 15: 55−58
  21. ^ Hopkin, M. (2005). Swordfish heat their eyes for better vision. Nature, 10 January 2005
  22. doi:10.1111/j.1095-8649.2008.01931.x. Archived from the original
    (PDF) on February 7, 2013. Retrieved 2 November 2012.
  23. ^ "Mola (Sunfish)". National Geographic. 2010-11-11. Archived from the original on February 4, 2010. Retrieved 28 October 2016.
  24. ^ Stan, Joshua (17 October 2022). "Discovered Remains of Sunfish in the Azores Set World Record as Largest Bony Fish". Science Times. Journal of Fish Biology. Retrieved 23 October 2022.
  25. ^ Busson, Frédéric; Froese, Rainer (15 November 2011). "Paedocypris progenetica". FishBase. Retrieved 13 January 2012.
  26. ^ Froese, Rainer; Pauly, Daniel (eds.) (2017). "Schindleria brevipinguis" in FishBase. September 2017 version.
  27. ISBN 9783899371598.{{cite book}}: CS1 maint: multiple names: authors list (link) CS1 maint: numeric names: authors list (link
    )
  28. ISBN 9788171338917
    .
  29. ISBN 978-0-03-910284-5
    .
  30. PMID 16572506
    .

Sources

Wikimedia Commons has media related to Osteichthyes.
Wikispecies has information related to Osteichthyes.
  • Helfman, G.S.; Facey, D.E. (1997). The Diversity of Fishes. Blackwell Sciences.
    ISBN 978-0-86542-256-8
    .
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