''Equulites klunzingeri'', or Klunzinger's ponyfish, is a marine, demersal species of

ponyfish Leiognathidae, the ponyfishes, slipmouths or slimys / slimies, are a small family of fishes in the order Perciformes. They inhabit marine and brackish waters in the Indian and West Pacific Oceans. They can be used in the preparation of ''bagoong' ...

from the family

Leiognathidae Leiognathidae, the ponyfishes, slipmouths or slimys / slimies, are a small family of fishes in the order Perciformes. They inhabit marine and brackish waters in the Indian and West Pacific Oceans. They can be used in the preparation of ''bagoong' ...

which was originally found only in the

Red Sea The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; T ...

. It is colonizing the

Mediterranean The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the e ...

as part of the

Lessepsian migration 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 ...

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 ...

Description

''Equulites klunzingeri'' has a laterally compressed, oblong body, large eyes and a downward pointing, protractile mouth, which can project to the same length as the head and with jaws line with villiform teeth. It has a long

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ...

, starting above the

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two en ...

s, which has seven spines, the second of which is very long, and 15-16 soft rays. The

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

has three spines and 15-16 soft rays. The dorsal and anal fin rays are sheathed in a scaly membrane. The tail is forked and the lateral lines continues on to the

caudal peduncle Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

. The skin is covered in small

cycloid In geometry, a cycloid is the curve traced by a point on a circle as it rolls along a straight line without slipping. A cycloid is a specific form of trochoid and is an example of a roulette, a curve generated by a curve rolling on another curve ...

scales. The upper part of the body is mottled grey marked with pink blotches while the belly is silvery white and there is a black line along either side of the base of the dorsal fin. There is another black line immediately anterior to the eye and the iris is golden. It grows to 11 cm

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 ...

Distribution

''Equulites klunzingeri'' is native to the Red Sea and it has been recorded in the

Sea of Oman The Gulf of Oman or Sea of Oman ( ar, خليج عمان ''khalīj ʿumān''; fa, دریای عمان ''daryâ-ye omân''), also known as Gulf of Makran or Sea of Makran ( ar, خلیج مکران ''khalīj makrān''; fa, دریای مکرا� ...

but not yet off the southern coast of the

Arabian Peninsula The Arabian Peninsula, (; ar, شِبْهُ الْجَزِيرَةِ الْعَرَبِيَّة, , "Arabian Peninsula" or , , "Island of the Arabs") or Arabia, is a peninsula of Western Asia, situated northeast of Africa on the Arabian Plate ...

. First recorded in the Mediterranean Sea off

Syria Syria ( ar, سُورِيَا or سُورِيَة, translit=Sūriyā), officially the Syrian Arab Republic ( ar, الجمهورية العربية السورية, al-Jumhūrīyah al-ʻArabīyah as-Sūrīyah), is a Western Asian country loc ...

in 1931 it has since invaded the eastern basin of the Mediterranean Sea by migrating through the

and now reaches up to the coast of

Croatia , image_flag = Flag of Croatia.svg , image_coat = Coat of arms of Croatia.svg , anthem = "Lijepa naša domovino"("Our Beautiful Homeland") , image_map = , map_caption = , capit ...

Atlas of Exotic Fishes in the Mediterranean Sea (Equulites klunzingeri). 2nd Edition. 2021. 366p. CIESM Publishers, Paris, Monaco.https://ciesm.org/atlas/fishes_2nd_edition/Equulites_klunzingeri.pdf

Biology

''Equulites klunzingeri'' is a demersal species, inhabiting inshore waters over sandy or muddy substrates and occurs down to a depth of 70m where it feeds on benthic invertebrates which are caught with the protruding mouth. It is

euryhaline Euryhaline organisms are able to adapt to a wide range of salinities. An example of a euryhaline fish is the molly (''Poecilia sphenops'') which can live in fresh water, brackish water, or salt water. The green crab (''Carcinus maenas'') is an e ...

and can enter estuarine environments. It spawns in the summer months, the eggs and larvae are

plankton Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...

ic. The females attain sexual maturity at 5.5 cm and the males at 5.8 cm, this equates to an age of about 2–3 years, the normal lifespan is 6 years. It is gregarious and forms schools, which can be large or small. ''E. klunzeringii'', like other members of the family Leiognathidae, uses a

bioluminescent Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some Fungus, fungi, microorganisms including ...

organ situated around its

oesophagus The esophagus (American English) or oesophagus (British English; both ), non-technically known also as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the ...

to camouflage the fish from below by

counter-illumination Counter-illumination is a method of active camouflage seen in marine animals such as firefly squid and midshipman fish, and in military prototypes, producing light to match their backgrounds in both brightness and wavelength. Marine animals of ...

, the bioluminescence is produced by symbiotic bacteria '' Photobacterium leiognathi''.

Fisheries

''Equulites klunzingeri'' is not a quarry species for fisheries but it is taken as a bycatch in fisheries using trawls and seines.

Taxonomy

''Equulites klunzingeri'' w was first formally described as ''Equula klunzingeri'' in 1898 by the

Austrian Austrian may refer to: * Austrians, someone from Austria or of Austrian descent ** Someone who is considered an Austrian citizen, see Austrian nationality law * Austrian German dialect * Something associated with the country Austria, for example: ...

ichthyologist Ichthyology is the branch of zoology devoted to the study of fish, including bony fish ( Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 33,400 species of fish had been described as of Octobe ...

Franz Steindachner with the type locality given as the

Gulf of Suez The Gulf of Suez ( ar, خليج السويس, khalīǧ as-suwais; formerly , ', "Sea of Calm") is a gulf at the northern end of the Red Sea, to the west of the Sinai Peninsula. Situated to the east of the Sinai Peninsula is the smaller Gulf of ...

in Egypt. Steindachner did not specify the identity of the person honoured in its specific name but it is clearly the

German German(s) may refer to: * Germany (of or related to) **Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ger ...

physician A physician (American English), medical practitioner (Commonwealth English), medical doctor, or simply doctor, is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through th ...

and

zoologist Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the Animal, animal kingdom, including the anatomy, structure, embryology, evolution, Biological clas ...

Carl Benjamin Klunzinger Carl Benjamin Klunzinger (18 November 1834, in Güglingen – 21 June 1914, in Stuttgart) was a German physician and zoologist. He studied medicine at the Universities of Tübingen and Würzburg, afterwards attending lectures on geology and ...

(1834-1914).

References

{{Taxonbar, from=Q926339 Klunzinger's ponyfish Fish of the Red Sea Klunzinger's ponyfish Taxa named by Franz Steindachner