Slender Tetra (Iguanodectes spilurus) Care Guide
Iguanodectes spilurus is an elongated South American tetra from Amazon and Orinoco tributaries, kept in soft-water groups.
Compiled by Aquairi from published sources · Published · Updated
Overview
Iguanodectes spilurus is a small, elongated characiform from northern South America. It is widely distributed across the Amazon, Orinoco, Essequibo and Tocantins river systems. The species has a slender silver body and a red-tipped lower caudal lobe. The largest recorded specimen measured about 10 cm.
Taxonomy
- Family: Characidae
- Genus: Iguanodectes
- Scientific name: Iguanodectes spilurus
- Note: FishBase currently places the genus in the family Iguanodectidae
Habitat
The species occurs in tributaries, smaller rivers, oxbows and flooded forests rather than main river channels. It is found both in transparent waters over sandy substrate and in blackwater and floodplain-lake environments. FishBase also records it from fast-flowing creeks.
Tank requirements
- Minimum tank volume: 100 L (26 gal)
- Temperature: 24-28 °C (75-82 °F)
- pH: 5.5-7.0
- GH: 1-10 °dGH
- School size: at least 6 individuals (8-10 recommended)
- Lifespan: 3-5 years
Diet
Iguanodectes spilurus is omnivorous. In the wild it feeds on small invertebrates and algae. In the aquarium it accepts a varied menu of dried foods alongside live and frozen items such as bloodworm, mosquito larvae, Daphnia and Moina.
Compatibility
This is a peaceful, mid-water schooling species suited to community aquariums. It should be kept in a mixed-sex group of at least eight to ten alongside other peaceful schooling fish, which encourages natural behavior and reduces stress.
Breeding
The species is an egg-scatterer. Nuptial males develop hooks and lappets on the anterior anal-fin rays, a feature used to distinguish breeding condition.
Conservation status
IUCN Red List: Least Concern (assessed 2020). It is used in both local fisheries and the aquarium trade and has low fishing vulnerability.
Slender Tetra Breeding Guide
Overview
The Slender Tetra (Iguanodectes spilurus) is a long, slender characid found in the Amazon, Essequibo, Orinoco and Tocantins river basins of South America, where it occurs in fast-flowing creeks. FishBase records that it spawns in intervals, but Seriously Fish provides no documented account of successful captive breeding, so the points below describe the general egg-scattering approach used for soft-water tetras.
Sexing
Seriously Fish notes that nuptial males develop hooks and lappets on the anterior anal-fin rays, which is the most reliable sexing cue when males are in breeding condition.
Conditioning
As a general egg-scatterer approach, condition the sexes on small live and frozen foods until females are visibly rounded with eggs before moving selected fish to a separate spawning tank.
Breeding Setup
- A dimly lit spawning tank, following the general soft-water tetra approach.
- Soft, slightly acidic water within the species' range: temperature about 23-27 C, pH 5.0-7.5, hardness up to 18 dH (FishBase).
- Fine-leaved plants or spawning mops, or a mesh base, to protect scattered eggs from the adults.
- Gentle filtration via an air-powered sponge filter.
Spawning Behavior & Trigger
Because aquarium spawning is undocumented, behaviour is inferred from related egg-scattering tetras: eggs would be scattered among plants or fall through a mesh base, and the adults should be removed promptly to prevent egg predation. FishBase notes only that the species spawns in intervals.
Egg & Fry Care
No species-specific egg or fry data are documented. Following the general tetra approach, free-swimming fry would be started on infusoria-type foods and moved on to microworm and brine shrimp nauplii as they grow.
Common Challenges
The main limitation is the absence of documented captive breeding, so a confirmed protocol does not exist for this species. Replicating its soft, fast-flowing creek water and conditioning ripe females are the key preliminaries.