Monday,26 July 2021, 4 : 54 PM

Aequidens tubicen

Aequidens tubicen
Image Credit: wikipedia


Aequidens tubicen is a moderate size fish of about 4.5 " found in Amazon River basin.
It is restricted to Trombetas River close to Cachoeira Porteira, Brazil.


(Click for details of Cichlid taxonomy)

Aequidens tubicen was first described by Kullander in 1991 and is placed in Genus Aequidens and subfamily Cichlasomatinae.
The Genus "Aequidens" is derived from Latin words, aequus+equal+dens(teeth), which roughly translates to "Fish with equal teeth".
The species name is derived from Latin noun meaning trumpeter, alluding to the name of the river drainage, the Trombetas, to which the species seems to be restricted.
In Portuguese trombetas means trumpets.


Aequidens tubicen is a omnivorous in nature, and eats small fish, deitrus.
It is a medium size fish with standard length about 6.5 ".
A. tubicen has a typical tri serial pre dorsal arrangement of scales of Aequidens with E1 scales 25 or 26.

The fish shows following characterstics:

  • The pectoral fin is large nearly 35% of Standard Length.
  • It has a enhanced, wide, light spot anterior to the caudal spot.
  • Lateral band is high on side.
  • Mid lateral spot is placed backwards on body
  • Vertebral number is high (usually 14 + 13 = 27)

These traits are also shown by A. pallidus, however it differs from it in following respects :
  • The cheek spot common to this genus is missing and there is an irregularly rounded blackish spot at the corner of the preopercle and adjacent cheek;
  • Lateral band which runs from head to dorsal margin of caudal peduncle,is interrupted by a large, elongate mid lateral spot and subdivided into 2 or 3 elongate spots posteriorly
  • Mid lateral spot is contiguous with or only narrowly separated from a wide dark bar running dorsally to the base of the dorsal fin.
    The spot and the bar together forming a strongly oblique, backwards slanting vertical marking.

It is known to live for 8-10 years.

Distribution & Habitat

Aequidens tubicen is restricted to Trombetas River close to Cachoeira Porteira, Brazil.
It prefers small, fast running creeks and rapids.
It is benthopelagic or swims above river/stream bed at depths of about 1-3 m in black water rivers.

Keeping in Aquarium

This fish has a very restricted distribution and is found in small, fast running creeks and rapids of Trombetas River close to Cachoeira Porteira, Brazil. with a ph of 4.5-6 and dh range 3-9.

Tank Size and setup:

Aequidens tubicen is a moderate sized fish and should be kept in a aquarium of about 300 liters with good filtration.
A sand bed of fine sand and many shelters with rocks and driftwood are ideal for this fish.
They are aggressive towards other species as well towards their own species.
At breeding time the aggression increases. Small fish should not be kept with them as it will be eaten.


Aequidens tubicen is dimorphic, and reach sexual maturity in about 9-11 months.
They lay eggs on flat surfaces and practice brood care.
Both parents take care of eggs and larvae.
The females are smaller and will clean a piece of flat rock and lay 300 eggs.
The eggs will hatch after 2-3 days and fry will be free swimming within a week.
Fry can be fed brine shrimp.
The pair will be ready to breed again if the fry are removed early.

Species Snapshot

Species Card

Particulars Details
Scientific Name Aequidens tubicen
Common Name Aequidens tubicen
Genus Aequidens
Subfamily Cichlasomatinae
Geographical Origin Amazon River basin, restricted to Trombetas River close to Cachoeira Porteira, Brazil.
Diet omnivore
Gender Differences Dimorphic
Breeding Substrate Spawner
Temperament Aggressive
Con Specific Temperament Aggressive
Water hardness Medium Soft, dh range 1-13
Difficulty Level in Aquariums 3

Morphometric Data

Particulars Details
Total Length(inches)
Standard Length(inches)

Measurements as % of Total Length

Particulars Details
Body Depth  %
Head length  %
Pre Dorsal length  %
Pre Pectoral length  %
Pre Anal length  %
Pre Pelvic length  %
Caudal Peduncle Depth  %
Caudal Peduncle Length  %
Fork length  %
Length of Last Dorsal Fin Spine  %
Pectoral Fin Length  %
Pelvic Fin Length  %

Measurements as % of Head Length

Particulars Details
Head Width  %
Snout length  %
Eye diameter  %
Pre Orbital Length  %
Inter Orbital Width  %
Pre Orbital Depth  %

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