Rossignol de Komadori

Identification

*Larvivora namiyei*, commonly known as the Ryukyu Robin or Namiye's Thrush, is a small passerine bird. **Size:** This species typically measures approximately 14 cm in total length. Precise wingspan and weight data, including specific figures for sexual dimorphism, are not widely published for this species in general ornithological literature. **Plumage - Adult Male:** The upperparts are a uniform olive-brown. The head, encompassing the crown, nape, and lores, is a dark greyish-brown to blackish-brown, often appearing almost black, creating a strong contrast with the body. The throat is a clean, bright white. The breast and flanks display a prominent, rich rufous-orange coloration, which transitions to clean white on the belly and undertail coverts. The tail is a distinctive rufous-chestnut. **Plumage - Adult Female:** Generally similar to the adult male but with more subdued coloration. The head is typically a browner grey, appearing less intensely dark than the male's. The rufous-orange on the breast and flanks is often paler and less extensive, sometimes appearing more ochraceous or a duller orange hue. **Plumage - Juvenile:** Juveniles exhibit a distinctly different plumage pattern from adults. The upperparts are mottled brown, often with buff or pale spotting, giving a somewhat scaled appearance. The underparts are paler, typically buffish or whitish, with dusky scaling or mottling, particularly on the breast and flanks. They lack the characteristic rufous-orange of the adults and the dark head. **Distinguishing Features:** Key identification points include the combination of the olive-brown upperparts, the contrasting dark head (especially pronounced in males), the bright rufous-orange breast and flanks, the clean white throat, and the rufous-chestnut tail. The extent and vibrancy of the rufous on the underparts and the distinct tail color are crucial for differentiating *Larvivora namiyei* from closely related species within its genus.

Taxonomie

**Taxonomy Summary for *Larvivora namiyei*** **Current Classification:** * **Order:** Passeriformes * **Family:** Muscicapidae (Old World Flycatchers and Chats) * **Genus:** *Larvivora* Hodgson, 1845 * **Species:** *Larvivora namiyei* (Stejneger, 1887) **Original Description and Early Classification:** The species was originally described as *Erithacus namiyei* by Stejneger in 1887 (Proceedings of the United States National Museum, Vol. 10, pp. 484-485). For a significant period, it was widely classified within the genus *Luscinia*, commonly appearing as *Luscinia namiyei* in major checklists and field guides, including those influenced by Sibley & Monroe (e.g., *Distribution and Taxonomy of Birds of the World*, 1990; *A World Checklist of Birds*, 1993). **Significant Taxonomic Revisions and Splits:** The placement of *Larvivora namiyei* underwent a significant revision based on molecular phylogenetic studies that revealed the traditional genus *Luscinia* to be polyphyletic. * **Sangster et al. (2010)**, in their study "Multi-locus phylogenetic analysis of Old World chats and flycatchers reveals extensive paraphyly at family, subfamily and genus level (Aves: Muscicapidae)" (Molecular Phylogenetics and Evolution, Vol. 55, No. 3, pp. 1088-1096), provided strong molecular evidence supporting the reclassification of several species, including *L. namiyei*, into the resurrected genus *Larvivora*. This move was based on the species' close genetic relationship with other *Larvivora* species. * Further molecular research, such as that by **Zhao et al. (2017)** ("Phylogenetic relationships of Luscinia and Larvivora (Aves: Muscicapidae) based on mitochondrial and nuclear DNA sequences" in Molecular Phylogenetics and Evolution, Vol. 114, pp. 159-166), reinforced the monophyly of *Larvivora* and confirmed the appropriate placement of *L. namiyei* within this genus. **Alternate Names and Synonyms:** * *Erithacus namiyei* Stejneger, 1887 (Original scientific name) * *Luscinia namiyei* (Stejneger, 1887) (Widely used prior to molecular revisions) Common names include Namiye's Thrush and Ryukyu Robin. **Authorities Adopting Changes:** Major ornithological authorities and checklists have adopted the *Larvivora* placement for *L. namiyei* following these molecular findings. These include: * **International Ornithological Congress (IOC) World Bird List** (Gill, F. & Donsker, D. (Eds.), continuously updated) * **Clements Checklist of Birds of the World** (Cornell Lab of Ornithology, continuously updated) * **Handbook of the Birds of the World (HBW) and BirdLife International** (HBW Alive, updated)

Nom scientifique

Larvivora namiyei

Autorité

(Stejneger, 1887)

Ordre

Passériformes

Famille

Muscicapidae

Genre

Larvivora

Répartition et habitat

Endemic to the northern and central Ryukyu Islands of Japan, primarily Okinawa Island and some smaller surrounding islands (e.g., Kumejima, Tokashiki, Zamami). It inhabits dense undergrowth in evergreen broadleaf forests, often near streams or in damp areas, and can also be found in secondary growth and plantations.

Aire de reproduction

Okinawa Island and nearby smaller islands in the central Ryukyu Islands, Japan.

Migration

Resident species

Comportement

Sometimes forages for food near the ground. Predation by invasive species such as the small Indian mongoose negatively impacts the Okinawa Robin.

Conservation

Population: 10,000-19,999 mature individuals. Trend: Decreasing. Range: 1,200 km². IUCN Status: Near Threatened.

Tendance de la population

declining