Centromochlus reticulatus (MEES, 1974)

Reticulated Driftwood Catfish

SynonymsTop ↑

Tatia reticulata Mees, 1974

Etymology

Centromochlus: from the Ancient Greek κεντέω (kentéo), meaning ‘sting, prick’ and μοχλός (mochlós), meaning ‘lever’, in reference to the prominent pectoral-fin spines in members of this genus.

reticulatus: from the Latin reticulatus, meaning ‘net-like, reticulated’, in reference to the colour pattern.

Classification

Order: Siluriformes Family: Auchenipteridae

Distribution

Initially known only from the upper Rupununi River basin in Guyana but it may have been overlooked elsewhere due to its secretive, mostly nocturnal behaviour.

For example, it’s been recorded in the rio Preto da Eva, a tributary of the Amazon a little downstream of Manaus in Amazonas state, Brazil and an identical-looking fish is sometimes exported from Peru.

Type locality is ‘Karanambo, Rupununi, Guyana’.

Habitat

In nature it takes refuge among submerged woody structures during the day, emerging to forage at night, and this habit gives rise to the common names of ‘wood’ or ‘driftwood’ catfishes for the family Auchenipteridae in general.

Maximum Standard Length

The largest officially-recorded specimen measured 27 mm.

Aquarium SizeTop ↑

An aquarium with base dimensions of 60 ∗ 30 cm or equivalent should be the smallest considered for general care.

Maintenance

Not difficult to maintain under the correct conditions; we recommend keeping it in a tank designed to simulate a flowing stream with a substrate of variably-sized rocks, sand, fine gravel, and some water-worn boulders.

This can be further furnished with driftwood branches, terracotta pipes, plant pots, etc., arranged to form a network of nooks, crannies, and shaded spots.

Centromochlus species also enjoy sheltering among surface vegetation such as Ceratopteris spp.

Water Conditions

Temperature: 22 – 28 °C

pH: 5.0 – 7.5

Hardness: 18 – 215 ppm

Diet

Centromochlus species will accept most sinking dried foods, but particularly relish small live and frozen varieties such as bloodworm, Tubifex, etc.

Once acclimatised they readily leave their hiding places when food is introduced and unlike most catfishes tend to actively feed at the surface.

Behaviour and CompatibilityTop ↑

A peaceful species which can be maintained in a well-chosen community alongside other small, quiet fishes.

It’s highly gregarious and ideally should be maintained in numbers of no less than 8.

Sexual Dimorphism

Adult males possess an elongated, relatively pointed anal-fin while that of the female is rounded, and the urogenital papilla in males emerges from a small flap of skin at the anal-fin origin.

Reproduction

All members of the family Auchenipteridae are thought to practise internal insemination and females can carry mature, unfertilised eggs and sperm packets inside the body for unspecified periods of time.

When conditions are satisfactory fertilisation is triggered and the eggs deposited, and there is no subsequent parental care.

NotesTop ↑

This species is sometimes traded as ‘purple oil catfish’ and is considered desirable in the aquarium hobby.

The genus Centromochlus is diagnosable by members having the proximal anal-fin radials enlarged and fused to each other at the base, forming a single ossified structure.

It’s sometimes included in the putative subfamily Centromochlinae which also includes Gelanoglanis, Glanidium, and Tatia.

This grouping is told apart from other auchenipterids by having modified anal-fin rays and proximal pterygiophores orientated posteriorly, a male urogenital papilla emerging from a flap of skin at the anal-fin origin,and the proximal anal-fin radials at least partially joined to each other.

The family Auchenipteridae is endemic to the neotropics and members are told apart from other catfishes by the following combination of characters: absence of bony plates on body; predorsal area covered in sutured bony plates clearly visible beneath a thin epidermis; absence of nasal barbels; adipose-fin small, occasionally absent; eye without a distinct orbital rim and covered by adipose tissue.

References

1. Ferraris, C. J., Jr., 2007 - Zootaxa 1418: 1-628
   Checklist of catfishes, recent and fossil (Osteichthyes: Siluriformes), and catalogue of siluriform primary types.
2. Reis, R. E., S. O. Kullander and C. J. Ferraris, Jr. (eds) , 2003 - EDIPUCRS, Porto Alegre: i-xi + 1-729
   Check list of the freshwater fishes of South and Central America. CLOFFSCA.
3. Soares-Porto, L. M. in Malabarba, L. R. et al.: Phylogeny and classification of Neotropical fishes, 1998 - EDIPUCRS, Porto Alegre: 331-350
   Monophyly and interrelationships of the Centromochlinae (Siluriformes: Auchenipteridae).