Home / Fishes / Catfish / Knobnose whiptail catfish, Pinocchio whiptail catfish
No federal permit to keepKnobnose whiptail catfish, Pinocchio whiptail catfish
Hemiodontichthys acipenserinus
Fishes › Catfish (Siluriformes) › Loricariidae (Plecos)
Hemiodontichthys is a monotypic genus of freshwater ray-finned fish belonging to the family Loricariidae, the suckermouth armored catfishes, and the subfamily Loricariinae, the mailed catfishes.
Care at a glance
Species-specific aquarium care
- Tank: At least 24 in long and 12 in front to back for one adult (adults commonly reach about 5.3 in / 13.4 cm).
- Water: Freshwater.
- Temperature: 75–82°F (range recorded for this species).
- Layout: Lives on or near the bottom: floor space and hiding places matter more than height.
- Diet: A predator: feed meaty foods sized to its mouth (frozen fish, shrimp, worms); it will eat tankmates that fit in its mouth. FishBase classes it as a carnivore.
- Availability: Rarely or never seen in the aquarium trade; expect to source it from specialists or not at all.
Calculated from this species' own FishBase record: tank size from its typical adult length and swimming zone, water values from its recorded ranges. The group guide below fills in general care.
Care guide
Species care notes
- Tank: a base of at least 30 × 12 in (roughly 18 US gallons); space needed is rated “modest tank”.
- Water: soft, acidic water, 75–82 °F, pH 6–7, 2–12 dGH.
- Difficulty: Moderate (Seriously Fish rating).
Short excerpts from the species profile:
- Setup: “There are two essential elements to a setup for this species.”
- Diet: “Omnivorous but mainly feeds on aquatic invertebrates by nature, so feed plenty of live and frozen foods such as bloodworm, daphnia, chopped earthworm etc.”
- Tankmates: “Very shy and retiring, to the point that it will be out-competed for food by many species.”
- Breeding: “Has been bred in aquaria, though not with any great regularity.”
From the Seriously Fish profile for this species, which has the full habitat, maintenance, diet, behaviour and breeding write-up 167
Plecos (suckermouth catfish)
Applies to most species in this group. Habitat: South American rivers. Individual species can differ, so compare with the species numbers above and the linked sources.
Housing & setup
- Driftwood (some species rasp it for fiber), caves and good flow.
- Common plecos reach 18–24 in; many smaller species stay under 6 in.
Diet
- Algae wafers and vegetables for herbivores; meaty foods for carnivorous species.
Health watch
- Starvation if they're expected to live on algae alone.
Understanding the animal
About this animal
About this animal
The only species in this genus is Hemiodontichthys acipenserinus, also known as the Pinocchio whiptail catfish, Pinocchio catfish, Pinocchio cat or the knob-nosed whiptail. This shy, bottom-dwelling catfish is native to the Guianas, Brazil, Bolivia and Perú in South America.
Quoted from the Wikipedia article “Hemiodontichthys” (CC BY-SA 4.0) 174
In the wild
In the wild
From this species’ own FishBase record (habitat, bottom type, water and breeding data), not its family. Good care copies these conditions.1
| Where it lives | Lives in freshwater. Stays near the bottom. Lives on sandy bottom where it feeds on worms and micro-crustaceans. Mature males develop a huge labial veil and teeth with spoon-shaped crow (versus pointed ones in females and juveniles). Unlike most Loricariidae, they don't have well developed odontodes on the snout and pectoral fins. During reproduction, the males bear a cluster of eggs fixed to their lips, which they provide with ventilation during movement. About one week after hatching, the alevins leave their parent's protection. |
| Water it lives in | Freshwater, 75–82 °F (24–28 °C). |
| Climate | Tropical climate. |
| Wild diet | Hunting macrofauna (predator). |
What this means for care
- Keep water within its wild range, 75–82 °F.
Native climate (measured)
Native climate (measured)
| Warm-season highs | about 90°F (up to 92°F in the hottest sampled areas) |
| Cool-season lows | about 68°F (down to 60°F in the coldest sampled areas) |
| Average temperature | 77–80°F across sampled records |
| Relative humidity | 78–84% on average (driest month about 76%) |
| Rainfall | about 2160 mm a year |
Measured at 179 wild occurrence records sampled against WorldClim 2.1 climate data (1970–2000 averages). Air conditions in the range are ecological context, not enclosure settings: microhabitats such as burrows, leaf litter or basking rocks can be cooler, warmer or more humid.
From the sources
From the sources
Quoted from the matching sections of reputable sources for this exact species. Specialist databases are used first; Wikipedia (community-edited, CC BY-SA 4.0) only fills gaps. Other sources are short credited quotes.
| Overview | Hemiodontichthys is a monotypic genus of freshwater ray-finned fish belonging to the family Loricariidae, the suckermouth armored catfishes, and the subfamily Loricariinae, the mailed catfishes. The only species in this genus is Hemiodontichthys acipenserinus, also known as the Pinocchio whiptail catfish, Pinocchio catfish, Pinocchio cat or the knob-nosed whiptail. This shy, bottom-dwelling catfish is native to the Guianas, Brazil, Bolivia and Perú in South America. — Wikipedia (community-edited) |
| Where it lives | Home ranges Population dynamics Growth parameters Max. ages / sizes Length-weight rel. Length-frequencies Mass conversion Recruitment Abundance Life cycle Reproduction Maturity Maturity/Gills rel. — FishBase |
| Appearance and size | Hemiodontichthys acipenserinus reaches a length of 13.4 cm SL. It has been reported that populations from the Amazonian region tend to be more slender than those from the Paraguay and Guaporé Rivers. — Wikipedia (community-edited) |
| Biology | Facultative air-breathing in the genus; Lives on sandy bottom where it feeds on worms and micro-crustaceans. Mature males develop a huge labial veil and teeth with spoon-shaped crow (versus pointed ones in females and juveniles). Unlike most Loricariidae, they don't have well developed odontodes on the snout and pectoral fins. — FishBase |
| History and naming | As a taxon, Hemiodontichthys is often compared with the morphologically-similar Reganella depressa, to the point that the two have been considered sister genera (on the basis of osteological data), although the similar external morphology of the two taxa may be viewed as evolutionary convergence, as the species occupy a similar ecological niche. — Wikipedia (community-edited) |
Data and studies
The numbers
The numbers
Each bar is what one source reports. Where several sources weigh in, the dashed gold band marks their average.
Adult length
Maximum recorded length. Measured as standard length (snout to the base of the tail, not counting the tail fin). Fish in home aquariums often stay smaller than wild records.
Water temperature
Range the species tolerates in nature; aim for the middle.
pH
Water hardness
Minimum tank footprint
Seriously Fish recommends a tank base of at least 30 × 12 in (about 18 US gallons).
Sources for this sheet
- FishBase (Froese & Pauly, eds.), version 24.07 Peer-reviewed researchThe global scientific database on fishes, maintained by a consortium of research institutions; every value is referenced.
- Seriously Fish species profiles Experienced keeper or breederLong-running aquarium reference written and peer-checked by experienced fishkeepers and ichthyologists; each profile covers habitat, tank size, water, diet, behaviour and breeding.
- Merck Veterinary Manual: Management of aquarium fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Merck Veterinary Manual: Types and features of aquatic systems Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Merck Veterinary Manual: Nutritional diseases of fish Zoo, university or veterinaryThe Merck Veterinary Manual: a standard veterinary reference written and reviewed by veterinary specialists.
- Seriously Fish — Ancistrus sp. “3” / common bristlenose identification Zoo, university or veterinaryAdded in the 2026 source-checked care-guide review.
- Wikipedia (species article) Community referenceFree encyclopedia; useful overviews with their own citations. Intro text is quoted under CC BY-SA 4.0.
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