Acanthodii
E413361
Acanthodii are an extinct class of early jawed fishes, often called "spiny sharks," that played a key role in the evolution of vertebrate jaws and fins.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Acanthodii canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T4111925 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Acanthodii Context triple: [Gnathostomata, subdivision, Acanthodii]
-
A.
Neopterygii
Neopterygii is a major clade of ray-finned fishes that includes most modern fish species, characterized by more advanced jaw mechanics and fin structures compared to more primitive actinopterygians.
-
B.
Sarcopterygii
Sarcopterygii is the class of lobe-finned fishes that includes the evolutionary ancestors of all tetrapods (amphibians, reptiles, birds, and mammals).
-
C.
Polypteriformes
Polypteriformes is an ancient order of ray-finned fishes that includes bichirs and reedfish, known for their elongated bodies, ganoid scales, and ability to breathe air.
-
D.
Erpetoichthys
Erpetoichthys is a genus of elongated, eel-like bichir fishes native to African freshwater habitats, best known for the ropefish (Erpetoichthys calabaricus).
-
E.
Chondrichthyes
Chondrichthyes is a class of cartilaginous fishes, including sharks, rays, and skates, characterized by skeletons made primarily of cartilage rather than bone.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Acanthodii Target entity description: Acanthodii are an extinct class of early jawed fishes, often called "spiny sharks," that played a key role in the evolution of vertebrate jaws and fins.
-
A.
Neopterygii
Neopterygii is a major clade of ray-finned fishes that includes most modern fish species, characterized by more advanced jaw mechanics and fin structures compared to more primitive actinopterygians.
-
B.
Sarcopterygii
Sarcopterygii is the class of lobe-finned fishes that includes the evolutionary ancestors of all tetrapods (amphibians, reptiles, birds, and mammals).
-
C.
Polypteriformes
Polypteriformes is an ancient order of ray-finned fishes that includes bichirs and reedfish, known for their elongated bodies, ganoid scales, and ability to breathe air.
-
D.
Erpetoichthys
Erpetoichthys is a genus of elongated, eel-like bichir fishes native to African freshwater habitats, best known for the ropefish (Erpetoichthys calabaricus).
-
E.
Chondrichthyes
Chondrichthyes is a class of cartilaginous fishes, including sharks, rays, and skates, characterized by skeletons made primarily of cartilage rather than bone.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
extinct class of jawed fishes
ⓘ
gnathostome ⓘ prehistoric vertebrate group ⓘ |
| bodyCovering |
small scales
ⓘ
sometimes reduced or absent scales on parts of body ⓘ |
| characterizedBy |
ganoid-like scales in some forms
ⓘ
large eyes ⓘ multiple paired fin spines ⓘ numerous fin spines ⓘ slender bodies ⓘ |
| clade | Gnathostomata ⓘ |
| commonName | spiny sharks ⓘ |
| controversialPlacement |
sometimes considered close to osteichthyan stem
ⓘ
sometimes considered stem-chondrichthyans ⓘ |
| diet | mostly small planktonic or nektonic organisms ⓘ |
| ecologicalRole |
planktivores
ⓘ
small to medium-sized nektonic predators ⓘ |
| extinction | became extinct by the end of the Permian ⓘ |
| finStructure | spines supporting all or most fins ⓘ |
| firstAppearance |
Silurian
ⓘ
surface form:
Silurian period
early Silurian ⓘ |
| fossilsFoundIn |
Asia
ⓘ
Australia ⓘ Europe ⓘ North America ⓘ South America ⓘ |
| had | jaws with small teeth or toothless margins ⓘ |
| kingdom | Animalia ⓘ |
| lastAppearance |
Permian Period
ⓘ
surface form:
Permian period
|
| livedIn |
freshwater environments
ⓘ
marine environments ⓘ |
| nameEtymology | derived from Greek "akantha" meaning spine ⓘ |
| notableGenus |
Acanthodes
ⓘ
Climatius ⓘ Ischnacanthus ⓘ |
| notCloselyRelatedTo | modern sharks ⓘ |
| phylum | Chordata ⓘ |
| playedRoleIn |
evolution of paired fins
ⓘ
evolution of vertebrate jaws ⓘ |
| resembles | sharks in overall body shape ⓘ |
| scientificSignificance |
important for understanding early evolution of jawed vertebrates
ⓘ
show mixture of bony fish and cartilaginous fish features ⓘ |
| skeletonType |
primarily cartilaginous
ⓘ
with some ossified elements ⓘ |
| status | extinct ⓘ |
| subphylum | Vertebrata ⓘ |
| temporalRange | Silurian–Permian ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Acanthodii Description of subject: Acanthodii are an extinct class of early jawed fishes, often called "spiny sharks," that played a key role in the evolution of vertebrate jaws and fins.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.