Genus · Plecos

Ancistrus

Ancistrus is a genus with 77 species in this atlas, catalogued in the Plecos section, recorded from Brazil, Peru, Venezuela and 12 more countries. Adult sizes run from 2 in to 8 in. Every species below links to a full researched profile.

Species in atlas: 77
Adult sizes: 2–8 in
IUCN assessed: 77 of 77 · 9 threatened
Recorded from: 15 countries

About the genus

Ancistrus is a genus of suckermouth armored catfish in the family Loricariidae, widespread across tropical South America and into Central America, with atlas records from Brazil, Peru, Venezuela, Colombia, Guyana, Paraguay, Argentina, and Bolivia. The 77 species in the atlas range from about 2–8 in and share the loricariid body plan: a flattened, bony-plated body and a ventral sucker-mouth used to graze algae and biofilm from submerged wood and rock. The genus's defining trait is the fleshy, branching tentacles that mature males grow across the snout, the bristles that give the group its common name of bristlenose pleco.

Ancistrus is one of the most widely kept catfish genera in the freshwater hobby: bristlenose plecos are valued as effective, peaceful algae grazers that stay smaller and more manageable than many other plecos, and species such as Ancistrus cirrhosus and A. dolichopterus (the starlight bristlenose) are commonly bred in home aquaria. Males use their snout tentacles in courtship and territorial display, then guard a clutch of eggs inside a cave or piece of wood until they hatch, a straightforward breeding project that has made the genus a staple of the aquarium trade for generations.

A handful of Ancistrus species, including Ancistrus cryptophthalmus and A. formoso, have adapted to life in Brazilian limestone caves and lost functional eyes entirely, an unusual case of cave-adapted evolution within a genus that is otherwise a sighted, surface-water group. Most assessed species are Least Concern, but several are Endangered or Vulnerable, and many, reflected in the large Not Evaluated and Data Deficient counts, are still too poorly studied for a confident status.

IUCN Red List: Endangered · 6 Vulnerable · 3 Near Threatened · 4 Least Concern · 38 Data Deficient · 10 Not Evaluated · 16

The 77 species

Every Ancistrus recorded in this atlas. Each card links to a full researched profile — distribution, water parameters, and aquarium care, cited to primary sources. 4 have hobbyist breeding reports (◉).

L032 · 2.5 in SL · LC

Ancistrus amaris

de Souza, Taphorn & Armbruster, 2019

4 in SL · NT

Ancistrus brevifilis

Eigenmann, 1920

Corroncho, Cucha, Guacuco

4.5 in SL · VU

Ancistrus brevipinnis

(Regan, 1904)

4 in SL · LC

Ancistrus bufonius

(Valenciennes, 1840)

Toad Bristlenose, Apurímac Bristlenose

4.5 in SL · LC

Ancistrus caucanus

Fowler, 1943

Cauca Bristlenose

2 in SL · LC

Ancistrus centrolepis

Regan, 1913

Northern Bristlenose, Colombian Bristlenose

7 in SL · LC

Ancistrus chagresi

Eigenmann & Eigenmann, 1889

Bristlenose Catfish, Chagres Bristlenose

7.5 in SL · LC

Ancistrus cirrhosus

◉

(Valenciennes, 1836)

Bristlenose pleco, Bristlenose catfish, Bushynose pleco

5 in TL · LC

Ancistrus claro

◉

Knaack, 1999

LDA008, LDA8, Gold Marble Bristlenose

LDA008 · 2.5 in SL · LC

Ancistrus clementinae

Rendahl, 1937

4 in SL · LC

Ancistrus cryptophthalmus

Reis, 1987

Blind Cave Bristlenose, Cave Bristlenose Catfish

2.5 in SL · EN

Ancistrus cuiabae

Knaack, 1999

Cuiabá Bristlenose

4.5 in SL · LC

Ancistrus damasceni

(Steindachner, 1907)

Parnaíba Bristlenose

2.5 in SL · LC

Ancistrus dolichopterus

◉

Kner, 1854

Starlight bristlenose pleco, Snowflake bristlenose, White-seam bristlenose

L183 · 5.5 in SL · LC

Ancistrus dubius

Eigenmann & Eigenmann, 1889

Dubious Bristlenose, Amazon Bristlenose

5 in SL · LC

3.5 in SL · NE

Ancistrus formoso

Sabino & Trajano, 1997

Blind Cave Bristlenose

3 in SL · VU

5.5 in SL · NE

Ancistrus hoplogenys

(Günther, 1864)

Orange Spotted Bristlenose, L059, Spotted Bristlenose Pleco

L059 · 6 in SL · LC

Ancistrus jataiensis

Fisch-Muller, Cardoso, da Silva & Bertaco, 2005

2 in SL · DD

Ancistrus jelskii

(Steindachner, 1876)

Jelski's Bristlenose, Andean Bristlenose

3 in TL · DD

6 in SL · LC

Ancistrus leoni

de Souza, Taphorn & Armbruster, 2019

3 in SL · LC

Ancistrus leucostictus

(Günther, 1864)

Bristlenose Catfish, White-Spotted Bristlenose

4 in SL · LC

Ancistrus lineolatus

Regan, 1904

Striped Bristlenose, Lined Bristlenose Pleco

3.5 in SL · NE

Ancistrus lithurgicus

Eigenmann, 1912

5 in SL · LC

Ancistrus luzia

Neuhaus, Britto, Birindelli & Sousa, 2022

L159

L159 · 3.5 in SL · LC

Ancistrus macrophthalmus

(Pellegrin, 1912)

Large-Eyed Bristlenose, Big-Eyed Bristlenose, LDA074

LDA074 · 3 in SL · LC

Ancistrus maculatus

(Steindachner, 1881)

4.5 in SL · DD

Ancistrus malacops

(Cope, 1872)

Carachama

3 in SL · LC

Ancistrus maracasae

Fowler, 1946

Maracas Bristlenose

4 in SL · NE

Ancistrus marcapatae

(Regan, 1904)

5 in TL · EN

Ancistrus martini

Schultz, 1944

Martin's Bristlenose Pleco, Bristlenose Catfish

3.5 in SL · LC

Ancistrus mattogrossensis

Miranda Ribeiro, 1912

Bristlenose Catfish

Ancistrus maximus

de Oliveira, Zuanon, Zawadzki & Rapp Py-Daniel, 2015

Giant Bristlenose, Red Spot Bristlenose, L110

L110 · 8 in SL · NE

3.5 in SL · LC

Ancistrus mullerae

Bifi, Pavanelli & Zawadzki, 2009

Müller's Bristlenose Pleco, Iguaçu Bristlenose

5 in SL · LC

Ancistrus multispinis

(Regan, 1912)

Thorned Bristlenose Catfish, Multi-spined Bristlenose

5.5 in SL · LC

Ancistrus nudiceps

(Müller & Troschel, 1849)

Naked-headed Bristlenose

L304 · 5.5 in TL · LC

Ancistrus occloi

Eigenmann, 1928

Carachama

4.5 in SL · LC

Ancistrus parecis

Fisch-Muller, Cardoso, da Silva & Bertaco, 2005

2.5 in SL · NT

Ancistrus patronus

de Souza, Taphorn & Armbruster, 2019

Patron Bristlenose Pleco

3.5 in SL · LC

Ancistrus pirareta

Fisch-Muller, Moullet & Loizeau, 1989

LDA053

LDA053 · 6 in SL · LC

Ancistrus piriformis

Muller, 1989

Pear-Shaped Bristlenose, Piriform Bristlenose

3.5 in SL · LC

Ancistrus ranunculus

◉

Muller, Rapp Py-Daniel & Zuanon, 1994

Medusa pleco, Monster bristlenose, Monsterantennenwels

L034 · 5.5 in SL · NT

5 in SL · NE

Ancistrus tamboensis

Fowler, 1945

Tambo Bristlenose

4.5 in SL · NE

Ancistrus taunayi

Miranda Ribeiro, 1918

Uruguay Bristlenose

5.5 in TL · LC

Ancistrus temminckii

(Valenciennes, 1840)

Bristlenose Catfish, Bushynose Pleco, Temminck's Bristlenose

4 in SL · NE

Ancistrus tolima

Taphorn, Armbruster, Villa-Navarro & Ray, 2013

3 in SL · EN

Ancistrus tombador

Fisch-Muller, Cardoso, da Silva & Bertaco, 2005

Tombador Bristlenose, Serra do Tombador Bristlenose

2.5 in SL · DD

Ancistrus trinitatis

(Günther, 1864)

Trinidad Bristlenose, Maracas Bristlenose

5 in SL · NT

Ancistrus triradiatus

Eigenmann, 1918

Bristlenose Catfish, Bristlenose Pleco, Three-rayed Bristlenose

3.5 in SL · LC

3 in SL · EN

Ancistrus yanesha

Neuhaus, Meza-Vargas, Herrera & Lujan, 2023

L267 Four-Stripe Ancistrus, Pyjama Bristlenose, Four-Stripe Bristlenose

L267 · 6 in SL · NE

Ancistrus yutajae

de Souza, Taphorn & Armbruster, 2019

Yutajé Bristlenose

3.5 in SL · EN

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How to cite

Aquarist Atlas (2026). Genus Ancistrus. Aquarist Atlas. https://www.aquaristatlas.com/ancistrus/

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