Sword-Tail Checkerboard Care Guide
Dicrossus gladicauda is a Colombian dwarf cichlid named for the sword-shaped caudal extension in males, a sensitive soft-acidic blackwater species.
Compiled by Aquairi from published sources · Published · Updated
Overview
Dicrossus gladicauda is a dwarf cichlid of the family Cichlidae described from the lower Rio Atabapo drainage in Colombia. The species name derives from the Latin gladius (sword) and cauda (tail), referring to the sword-like streamer formed by extended caudal-fin rays in adult males. It is a sensitive blackwater species.
Taxonomy
- Family: Cichlidae
- Genus: Dicrossus
- Scientific name: Dicrossus gladicauda
Habitat
The species inhabits clear, acidic and very soft, tea-coloured blackwater with dense vegetation and leaf litter on the bottom, in the Atabapo drainage of the Inirida system. FishBase records that it occurs at roughly 10-50 cm depth with total and temporary hardness below 1 degree dH.
Tank requirements
- Minimum tank volume: 80 L
- Temperature: 25-29 °C (77-84 °F)
- pH: 4.0-6.0
- GH: 1-3 °dGH
- Water flow: low
- Lifespan: 3-5 years
FishBase reports water from pH 4.4 upward and temperatures from 24 °C; a soft, acidic, heavily planted blackwater layout with leaf litter best matches the natural habitat.
Diet
A carnivore in the aquarium, taking small live and frozen foods, fed about twice daily. Soft acidic conditions are important for conditioning this species.
Compatibility
A peaceful, mid-water dwarf cichlid suited to soft-water community tanks with small tetras and corydoras. Large tetras and aggressive cichlids should be avoided.
Conservation status
IUCN Red List: Endangered, assessed in 2020 under criterion B1ab(iii). Its restricted range in the Atabapo drainage makes it vulnerable to habitat change.
Dicrossus gladicauda Breeding Guide
Overview
Dicrossus gladicauda is a checkerboard dwarf cichlid from the lower Río Atabapo drainage in Colombia (FishBase). FishBase records a maximum standard length of 4.2 cm, and the species name derives from Latin gladius (sword) and cauda (tail), referring to the sword-like streamer of the dorsal lobe of the caudal fin in adult males. No species-specific spawning account was found in the consulted whitelisted sources, so breeding is described following the biology of its congener Dicrossus filamentosus.
Sexing
FishBase notes the diagnostic male sword-shaped caudal extension. In the closely related D. filamentosus, males are slightly larger and develop an attractive elongated caudal fin, while females are smaller with rounded fins (Seriously Fish). Definitive species-specific dimorphism beyond the male caudal streamer is not detailed in the consulted sources.
Conditioning
For the genus, live foods are highly recommended to bring fish into breeding condition (Seriously Fish, for D. filamentosus). The KB record classifies D. gladicauda as a carnivore fed twice daily.
Breeding Setup
Dicrossus are demanding regarding water chemistry: in D. filamentosus, breeding succeeds only in premium soft, acidic conditions, with reverse-osmosis water nearly mandatory, hardness of 1 dGH or lower, and temperatures of 27-30 °C (Seriously Fish). The KB record for D. gladicauda lists a minimum volume of 80 L with temperatures of 25-29 °C, pH 4-6 and GH 1-3.
Spawning Behavior & Trigger
Genus members spawn on solid surfaces, and live foods are used as a conditioning trigger (Seriously Fish, for D. filamentosus). A species-specific spawning sequence for D. gladicauda was not documented in the consulted sources.
Egg & Fry Care
Across Dicrossus, eggs will not hatch above roughly pH 5.8, so eggs require very soft, acidic water to develop (Seriously Fish, for D. filamentosus). Detailed clutch size and fry-rearing data specific to D. gladicauda are not available in the consulted sources.
Common Challenges
The KB record rates breeding difficulty as advanced. The principal challenge is achieving and stabilising the very soft, acidic water the genus requires for eggs to develop, as documented for its congener (Seriously Fish).