Epimachus

Epimachus is a genus of birds-of-paradise (Paradisaeidae) that includes two species, found in the highland forests of New Guinea. They are the largest members of the family. The common name "sicklebill" refers to their long, decurved, sickle-shaped bill.[1]

Epimachus
Brown sicklebill, Epimachus meyeri
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Family:	Paradisaeidae
Genus:	Epimachus Cuvier, 1816

Sicklebills often associate with astrapias, which are superficially similar but have a short, straight bill and blunt-tipped tail, and the male’s wings hiss in flight.[1]

The Epimachus birds are often referred to as "long-tailed" sicklebills, when describing them collectively as a genus. The other sicklebills, genus Drepanornis, are referred to as the "short-tailed" sicklebills. Ironically, the two genera are not closely related. There may also be confusion with the birds of the same name that belong to the hummingbird family, found in the Americas.

Taxonomy

Etymology

Epi comes from the Greek, meaning over or upon, and machaira, a curved sword, referring to the scimitar-like bill.[2]

In 1972, the genus was merged with the genus Drepanornis,[3] but separated again in 1998.[4] A phylogenetic study placed Epimachus in a clade that includes Paradigalla and Astrapia, implying that the long, curved bill has been acquired independently in Epimachus. According to the same study, the Drepanornis species are closely related to the Twelve-wired bird-of-paradise, Standardwing bird-of-paradise, superb birds-of-paradise, and the riflebirds.[5]

The two species of Drepanornis as well as the two species of Epimachus separated about 10 and 7 mya, respectively.[5] While the two species of Drepanornis occupy different elevations in low- and mid-montane forests, the two species of Epimachus are altitudinal replacements in mountain forests; these two cases could represent old cases of altitudinal speciation.[5]

Species

Image	Common Name	Scientific name	Distribution
	Black sicklebill	Epimachus fastosus	Found in the Vogelkop region, Wandammen peninsula, and central New Guinea at altitudes of 1500-2000 m.
	Brown sicklebill	Epimachus meyeri	Found across central New Guinea to the Bird's Tail region (Papuan Peninsula) to the southeast at altitudes from 2000 to 3000 m.

Description

Both species of Epimachus are sexually dimorphic. The males of these birds are highly eccentric, with hyperbolically long, saber-like, black tails that reach around 18 inches (46 cm) alone. They also feature two pectoral fan-like plumes on each side of the breast,[4] which they bring up over their heads during their displays.

There is extensive green/purple iridescent highlights found on the head and back of the adult male;[1][4] additionally, blue gloss is present on the tail. The females of both species both have barred underparts, olive-brown upperparts and relatively long tails, though not as extensive as the males' tails.

Distribution and habitat

Sicklebills are endemic to New Guinea, sympathetically inhabiting areas of montane rainforest and cloud forest along the central mountainous axis of the island.

Brown sicklebills are more common,[2] inhabiting mid and upper-mountain forests,[6] including mossy cloud forest, above the elevations of other sicklebills. Black sicklebills are more rare and inhabit the transition from mid-mountain to cloud forest, occasionally forest edges.[1][7]

References

1. Pratt, Thane K. (26 October 2014). Birds of New Guinea. Beehler, Bruce McP,, Bishop, K. David,, Coates, Brian J.,, Diamond, Jared M.,, Lecroy, Mary,, Anderton, John (Second ed.). Princeton, New Jersey. ISBN 978-1-4008-6511-6. OCLC 894139572.
2. Gregory, Phil (2020). Birds of Paradise and Bowerbirds. Bloomsbury Publishing. p. 248. ISBN 9781472975843.
3. Diamon, Jared M. (1972). Avifauna of the eastern highlands of new guinea. [Place of publication not identified]: Harvard Univ Nuttall Orni. ISBN 1-877973-22-X. OCLC 948758073.
4. Frith, Clifford B.; Beehler, Bruce M. (1998). Birds of Paradise. New York: Oxford University Press. ISBN 9780198548539.
5. Irestedt, Martin; Jønsson, Knud A.; Fjeldså, Jon; Christidis, Les; Ericson, Per GP (2009-09-16). "An unexpectedly long history of sexual selection in birds-of-paradise". BMC Evolutionary Biology. 9 (1): 235. doi:10.1186/1471-2148-9-235. ISSN 1471-2148. PMC 2755009. PMID 19758445.
6. "Black Sicklebill". The Australian Museum. Retrieved 21 September 2020.
7. "Black Sicklebill". The Australian Museum. 4 August 2019. ABN 85 407 224 698. Retrieved 21 September 2020.