About the Adolfo's Cory
Species Type: Freshwater Fish
Care Level: Moderate. May tolerate only a narrow range of water parameters, have specific dietary requirements including frozen or even live foods, may have behaviors that severely limit potential tankmates or may require a specialized aquarium setup.
Origin: Endemic to a small north-side tributary of the upper Rio Negro near Sao Gabriel da Cachoeira, Brazil. The stream is slow-flowing with a sandy substrate littered with branches; the fish reside along the banks.
Compatibility/Temperament: Peaceful, typical Cory species that should be kept in a group of at least three but preferably five or more of its own species. Perfect for a community aquarium of non-aggressive fish with similar water requirements.
This species was the first of several species that share a similar colour pattern to be discovered [see below]; it was described and named by Burgess in 1982 in honour of the fish collector Adolfo Schwartz. A sympatric species having an identical colour pattern but with a longer snout was subsequently discovered, and described and named C. imitator [= to imitate] by Nijssen & Isbrucker, 1983. In the above photos, C. adolfoi is the left photo and C. imitator the right photo.
Some 12 new species were discovered during the 1980's and 1990's, all endemic to specific southerly-flowing tributaries of the upper Rio Negro, and having very similar cryptic (camouflaging) colour patterns. When viewed from above in the habitat, the colour pattern of all these fish cause them to blend in with the twigs and branches that litter the buff-coloured streambeds. The patterns include a buff-coloured body with a black dorsolateral band (that may only be partial on some species), a black eye band, and an orange post orbital fleck in the shape of a "V" when viewed from above, the intensity of which varies between the species.
A well-planted tank containing some pieces of bogwood and some open substrate (small gravel or sand, provided it is smooth-edged) will suit this fish. As with all Cory's, mature females are rounder when viewed from above. C. adolfoi is not as common in the hobby now, having been replaced by the more colourful False Adolfo Cory, Corydoras duplicareus.
The Corydoras are quite sensitive to water parameters and quality, and highly intolerant of salt, chemicals and medications. Signs of stress usually begin with rapid respiration, then lethargy (often just "sitting" on plant leaves, wood or the substrate respirating heavily, sometimes near the surface) and sometimes rolling onto one side. At such signs, a partial water change of at least 50% with a good water conditioner should immediately be made, and appropriate steps taken to remove the cause. Any sudden fluctuation in water chemistry or temperature often induces shock, causing the fish to "faint" and fall over on its side. Corydoras introduced to new aquaria will settle in better if the tank is established; Cory's do not adjust well to a new aquarium with still-unstable water conditions and fluctuations.
The dorsal, pectoral and adipose fins are each preceded by a spine which is actually a hardened and modified ray; the pectoral fin spine can be "locked" into position by the fish; care must be taken when netting Cory's not to entangle these spines, which can also give the aquarist a nasty jab. They are believed to be a defense adaptation, to lodge the fish in the throat of a predator.
All species in the genus will periodically and fairly regularly swim quickly to the surface for a gulp of air. The fish swallows the air and blood vessels in the hind gut extract oxygen from the air; it is then expelled through the vent the next time the fish breaks the surface for another gulp of air. This adaptation is believed to have evolved so that the fish can survive in poorly-oxygenated water such as drying pools during the dry season. It is however essential to the fish's well-being that it regularly swallows air.
The genus name is derived from the Greek "Cory" meaning helmet, and "doras" meaning skin, incorrectly used here for "armour"; it refers to the dual row of overlapping plates (instead of scales) along the body, comparable to a suit of armour.
Adolfo's Cory Diet
Feeds on worms and insect larvae in its habit; will readily accept prepared sinking foods like tablets and pellets, and frozen bloodworms and live worms will be relished as treats.
Grows to 2.5 inches.
Minimum Tank Suggestion
24 inches in length.
Ideal water parameters for Adolfo's Cory
Soft (hardness below 10 dGH) acidic (pH below 7.0) water, temperature 20-26C/68-79F. Tank-raised fish may adapt to slightly basic water, pH up to 7.6 and moderate hardness to 20 dGH. The parameters of the habitat creek are pH 6.2-6.5 with a temperature around 23C.