Iduna aedon (Pallas, 1776)

Scientific Naming

The thick-billed warbler, previously known by the scientific name Arundinax aedon, currently has the scientific name Iduna aedon (Pallas, 1776).

Breeding Range

This species breeds in the temperate east Palearctic, ranging from south Siberia to west Mongolia.

Migratory Patterns

It is a migratory bird, and it winters in tropical South Asia and South-east Asia. It is a very rare vagrant in western Europe.

Habitat

This passerine bird lives in dense vegetation including reeds, bushes, and thick undergrowth.

Reproduction

Females lay five or six eggs in a nest built in a low tree.

Size

This is a large warbler, measuring 16–17.5 cm (6.3–6.9 in) in length, which is nearly as big as the great reed warbler.

Adult Plumage

Adult thick-billed warblers have an unstreaked brown back, buff underparts, and few obvious distinctive plumage features.

Head and Bill Morphology

They have a rounded forehead and a short, pointed bill.

Sexual Dimorphism

As with most warblers, the sexes look identical.

Juvenile Plumage

Young birds are a richer buff color on their underparts than adults.

Diet

Like most warblers, the thick-billed warbler is primarily insectivorous, but it will also eat other small prey items.

Vocalization

Its song is fast and loud, similar to the song of the marsh warbler; it includes extensive mimicry, plus the acrocephaline whistles typical of this group of warblers.

Historical Taxonomy

This species has had multiple taxonomic placements over time. It was sometimes placed in the monotypic genus Phragmaticola (or misspelled Phragamaticola), and was classified within the genus Acrocephalus for a long time.

2009 Taxonomic Proposal

In 2009, researchers suggested it belonged to the Iduna clade.

2014 Phylogenetic Study Findings

However, a 2014 phylogenetic study using a larger set of genetic loci found that the species did not actually fit within the Iduna clade. That study therefore recommended resurrecting either the genus Phragamaticola or Arundinax.

Genus Name Priority

Arundinax is the older available genus name, so it has taxonomic priority.

Genus Name Etymology

The genus name Arundinax comes from Latin arundo, arundinis meaning "reed", and Ancient Greek anax meaning "master".

Specific Epithet Etymology

The specific epithet aedon comes from Ancient Greek aedon, which means nightingale. In Greek mythology, Queen Aëdon was transformed into a nightingale after she accidentally killed her own son Itylus, when she intended to murder one of the sons of her sister-in-law Niobe.