Derichthyidae
neckeel
Derichthys serpentinus
FISH SPECIES
An eel-shaped fish is not automatically a true eel. The word describes both a familiar silhouette and, in everyday speech, several animals that belong to different groups. A useful first question is therefore not “Which eel is this?” but “What evidence places this fish among the true eels?” Starting with that distinction prevents mistakes that can spread from an image caption into assumptions about habitat, behavior and care.
01 / NATURAL HISTORY
Begin a visual comparison with features that the image actually shows. Can you see the outline of the head, the position of the mouth, a pectoral fin, and the course of the fins along the body? Write down those observations before comparing names. If the fish is partly concealed, record the hidden parts as unknown. A fin outside the frame is not evidence of an absent fin.
02 / LIFESTYLE
The American eel provides a clear example of a life cycle that crosses habitats. NOAA describes its young entering estuaries and occupying fresh or coastal waters as they grow, before mature fish migrate toward the Sargasso Sea to reproduce. “Freshwater eel” therefore describes only part of the ecological story; an observation in a river does not establish that the entire life cycle takes place there.
OBSERVATION INDEX
03 / SPECIES
Discover representative species illustrating the ecological diversity, morphologies and adaptations of this group.
Derichthyidae
Derichthys serpentinus
Congridae
Rhynchoconger nitens
Congridae
Bathycongrus vicinalis
Anguillidae
Anguilla dieffenbachii
Congridae
Conger jordani
Congridae
Conger monganius
Muraenidae
Gymnothorax nuttingi
Muraenidae
Gymnothorax ocellatus
Ophichthidae
Lamnostoma polyophthalmus
Ophichthidae
Ophichthus olivaceus
Ophichthidae
Ophichthus rutidoderma
Muraenidae
Gymnothorax megaspilus
Muraenidae
Gymnothorax monostigma
Ophichthidae
Apterichtus hatookai
Myrocongridae
Myroconger nigrodentatus
Ophichthidae
Apterichtus flavicaudus
Ophichthidae
Scolecenchelys xorae
Ophichthidae
Myrophis microchir
Ophichthidae
Lamnostoma orientale
Ophichthidae
Herpetoichthys regius
Heterenchelyidae
Pythonichthys asodes
Ophichthidae
Paraletharchus pacificus
Anguillidae
Anguilla obscura
Ophichthidae
Ophichthus triserialis
04 / FIELD NOTES
No. These are available published records with images, not an exhaustive inventory or a measure of abundance.
Follow the scientific name and source, check the scope of the evidence, and send a correction with the exact claim if needed.