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alder fly

alder fly

9.9
A dark insect whose young live in water and eat other small animals
  • noun
translation icon : mosca de aliso
  • The larvae of the alder fly are known to be fierce aquatic predators.

Examples

  • Fishermen often use alder fly imitations as bait for trout.

  • We found an alder fly resting on a leaf by the riverbank.

  • The alder fly is often found near rivers.

  • Many alder flies inhabit freshwater streams.

  • The larvae of the alder fly are known to be fierce aquatic predators.

  • Fishermen often use alder fly imitations as bait for trout.

  • The alder fly is often found near rivers.

Synonyms

Sialis lutaria
vsalder fly
  • Specialized
9.9

A dark insect called an alderfly whose young live and hunt in fresh water

is the common family term for the insect rather than a scientific name
alderfly
vsalder fly
  • UK
9.9

A dark insect that lives near water whose young live in water and eat small insects

is the same idea but without geographic distribution detail

Surface Forms

alder fly singular
alder flies plural

Morphology

alder + fly

This is a straightforward noun+noun compound where 'alder' modifies 'fly', so a B1 learner who knows both words will infer it is a type of fly associated with alder trees; although the precise biological details (family Sialidae, aquatic predatory larvae) are not predictable, the basic referent is transparently compositional. Modifier+head animal names are a common, cross-linguistic naming pattern, making the overall meaning accessible from the parts.

Etymology

Alder fly is named for the dark insect you find by rivers: adults sit on alder trees and it is a fly, while the young live in the water. Because those young are fierce water hunters and the adults are common at the river edge, fishermen copy the insect as 'bait', so the name brings to mind the river insect used to catch trout.