Synodontis macrostoma, known as the largemouth squeaker,[2] is a species of upside-down catfish that is native to Namibia and Zambia where it is found in the Kafue, upper Zambezi, Okavango and Cunene Rivers.[3] It was first described by Paul H. Skelton and Peter N. White in 1990. The original specimens were obtained in Upper Zambezi River at Katima Mulilo, Caprivi, Namibia.[2] The species name macrostoma means "large mouth", which refers to its distinctive large mouth.[4]
| Synodontis macrostoma | |
|---|---|
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Siluriformes |
| Family: | Mochokidae |
| Genus: | Synodontis |
| Species: | S. macrostoma
|
| Binomial name | |
| Synodontis macrostoma P. H. Skelton & White, 1990
| |
Description edit
Like all members of the genus Synodontis, S. macrostoma has a strong, bony head capsule that extends back as far as the first spine of the dorsal fin.[5] The head contains a distinct narrow, bony, external protrusion called a humeral process.[2] The fish has three pairs of barbels. The maxillary barbels are on located on the upper jaw, and two pairs of mandibular barbels are on the lower jaw.[6] The adipose fin is large and the tail, or caudal fin, is forked.[2]
The front edges of the dorsal fins and the pectoral fins are hardened into stiff spines. These spines can be raised into position at right angles to the body and locked into position for defensive purposes.[7][8] The ability to lock the spines into place comes from several small bones attached to the spine, and once raised, the spines cannot be folded down by exerting pressure on the tip.[8]
The fish has a structure called a premaxillary toothpad, which is located on the very front of the upper jaw of the mouth. This structure contains several rows of short, chisel-shaped teeth. On the lower jaw, or mandible, the teeth are attached to flexible, stalk-like structures and described as "s-shaped" or "hooked".[2][5]
The maximum standard length of the species is 9.2 centimeters (3.6 in).[3] Generally, females in the genus Synodontis tend to be slightly larger than males of the same age.[9]
Habitat and behavior edit
In the wild, the species favors fast-flowing, rocky stretches of river, where it is fairly common.[1] As a whole, species of Synodontis are omnivores, consuming insect larvae, algae, gastropods, bivalves, sponges, crustaceans, and the eggs of other fishes.[10] The reproductive habits of most of the species of Synodontis are not known, beyond some instances of obtaining egg counts from gravid females.[10] Spawning likely occurs during the flooding season between July and October, and pairs swim in unison during spawning.[11] The growth rate is rapid in the first year, then slows down as the fish age.[9]
References edit
- ^ a b Marshall, B.E. & Tweddle, D. (2007). "Synodontis macrostoma". The IUCN Red List of Threatened Species. 2007. IUCN: e.T63374A12651702. doi:10.2305/IUCN.UK.2007.RLTS.T63374A12651702.en. Retrieved 15 January 2018.
- ^ a b c d e "Synodontis macrostoma Skelton & White, 1990". Planet Catfish. 31 Jan 2013. Retrieved 7 November 2016.
- ^ a b Froese, Rainer; Pauly, Daniel (eds.) (2016). "Synodontis macrostoma" in FishBase. June 2016 version.
- ^ Scharpf, Christopher & Kenneth Lazara (12 Sep 2016). "Order SILURIFORMES: Families MALAPTERURIDAE, MOCHOKIDAE, SCHILBEIDAE, AUCHENOGLANIDIDAE, CLAROTEIDAE and LACANTUNIIDAE". The ETYFish Project. Retrieved 7 November 2016.
- ^ a b Cuvier, Georges (1934). The Animal Kingdom Arranged in Conformity with its Organization, Volume 10. Translated by Griffith, Edward. London: Whittaker and Co. p. 406.
- ^ Boulenger, George Albert (1909). Catalogue of the fresh-water fishes of Africa in the British museum (Natural history). London: British Museum. p. 391.
- ^ Nelson, Joseph; T. Grande & M. Wilson (2016). Fishes of the World (Fifth ed.). John Wiley and Sons. p. 227.
- ^ a b Scherge, M.; S. Gorb & S. Gorb. Biological Micro- and Nanotribology. Springer Science & Business Media. pp. 97–98.
- ^ a b H. M. Bishai & Y. B. Abu Gideiri (1965). "Studies on the biology of genus Synodontis at Khartoum". Hydrobiologia. 26 (1–2): 85–97. doi:10.1007/BF00142257.
- ^ a b Wright, J.J. & L.M. Page (2006). "Taxonomic Revision of Lake Tanganyikan Synodontis (Siluriformes: Mochokidae)". Florida Mus. Nat. Hist. Bull. 46 (4): 99–154.
- ^ John P. Friel & Thomas R. Vigliotta (March 2, 2009). "Mochokidae Jordan 1923: African squeaker and suckermouth catfishes". Tree of Life Web Project. Retrieved 19 October 2016.
External links edit
Data related to Synodontis macrostoma at Wikispecies