Cat-eLog Right Loricariidae Right Hypostominae Right Aphanotorulus  |  | 

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Scientific Name Aphanotorulus emarginatus  (Valenciennes, 1840)
Common Names L011, Red Fin Thresher Pleco
L035, L108, L116, Tærskesugemalle (Denmark)
Type Locality Probably from Brazil.
Synonym(s) Hypostoma squalinum, Hypostomus annae, Hypostomus emarginatus, Hypostomus squalinus, Plecostomus annae, Squaliforma annae, Squaliforma emarginatus, Squaliforma squalina
Pronunciation ah FAN oh to RULE uss
Etymology Greek, aphanes = hidden + Latin, torulus, -i = muscle, little string. 
Down Species Information
Size 400mm or 15.7" SL. Find near, nearer or same sized spp.
Identification In Aphanotorulus, all species show clear sexual dimorphism and have a generally flatter appearance than other hypostomine genera. The posterior edge of the oral disc is jagged rather than smooth. Aphanotoroulus can be distinguished from Isorineloricaria by having caudal peduncles that do not become greatly lengthened with size and that are oval in cross section (vs. caudal peduncle proportions that get proportionately longer with size and that become round in cross-section), and by having small dark spots (less than half plate diameter) on a light tan background (vs. spots almost as large as lateral plates on a nearly white background.

An elongate species that appears widespread throughout the Amazon and correspondingly has acquired a series of L numbers. We are talking about a very widely distributed, variable species. In terms of distribution and regional variation this species is to the Loricariidae what Corydoras aeneus is to the Callichthyidae. Can be most readily distinguished by its long crescent shaped caudal fin which has a red or orange outer margin.
Sexing Males in breeding condition posses extremely elongate, bristle-like odontodes. These cover the entire back and sides behind the dorsal fin.
General Remarks L108 - DATZ 9/1992 p552 L116 - DATZ 10/1992 pp619-620.
Down Habitat Information
Distribution L011 - Brazil: Rio Xingú at Altamira.
L035 was introduced from Brazil, specifically the Rio Araguaia, just upstream of confluence with the Rio Tocantins.
L108 - Ecuador: Upper Rio Napo.
Brazil, Pará, Rio Trombeta (Oriximiná).
Amazon, Lower Amazon, Xingu (click on these areas to find other species found there)
Amazon, Lower Amazon, Tocantins, Lower Tocantins, Araguaia (click on these areas to find other species found there)
Amazon, Lower Amazon, Trombetas (click on these areas to find other species found there)
Amazon, Upper Amazon, Napo, Upper Napo (click on these areas to find other species found there)
Amazon, Middle Amazon (Solimoes), Negro (click on these areas to find other species found there)
Amazon, Middle Amazon (Solimoes), Negro, Lower Negro, Branco (Roraima) (click on these areas to find other species found there)
Guyana Waters, Coastal Rivers of Guyanas, Essequibo (click on these areas to find other species found there)

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IUCN Red List Category Least Concern, range map and more is available on the IUCN species page. Last assessed 2020.
pH 6.4 - 7.2
Temperature 25.0-28.0°C or 77-82.4°F (Show species within this range)
Other Parameters dH 5-5.8
Down Husbandry Information
Feeding An adaptible omnivore with a preference towards greens. Cucumber or similar should be offered periodically but this fish with do well an most sinking pellet food. User data.
Furniture Open shaded spaces sized appropriately to the fish, this fish likes to swim in and out fast and so space must be given to avoid mistakes when the fish is in flight. Large terracotta pipes are ideal, doesn't appear to have a requirement for bogwood or plants.
Compatibility Requires space as an adult fish as is more flighty than, say, Pterygoplichthys spp. Peaceful with plecos even one third of its size.
Suggested Tankmates Medium to large sized community fish and ideal and pretty addition to a south american cichlid tank, will withstand life in a well oxygenated discus tank and is a good pleco as such as it rarely leaves the bottom.
Breeding Unreported.
Breeding Reports There is but a single breeding report, read it here.
Down Further Information
Reference Histoire naturelle des poissons v. 15, pp 500.
Registered Keepers There are 25 registered keepers, view all "my cats" data.
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There are 8 wishes to keep this species, see who wants what.
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There are 17 records of this fish being seen, view them all.
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Last Update 2022 Jan 13 12:40 (species record created: 2001 Nov 24 00:00)