Silk ducks
| Silk ducks | ||||||||||
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Giant Silk Cuckoo ( Coua gigas ) |
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| Scientific name | ||||||||||
| Coua | ||||||||||
| Schinz , 1821 |
The coua ( Coua ) are a genus in Madagascar endemic cuckoos (Cuculidae). They resemble the African turacos (Musophagidae) and like them have a zone of bare skin around the eyes. Like all cuckoos, they can turn their third toe both forward and backward. Three of the nine species live in the rainforests of the eastern lowlands, while the other six live in the arid regions of Madagascar's west and south. The smallest silk cuckoo, the yellow-throated silk cuckoo ( Coua cursor ), weighs 120 grams, while the giant silk cuckoo (Coua gigas ) up to 400 grams, becomes heavy.
nutrition
Silkworms are omnivores and feed on fruits, seeds, leaves, tree sap, insects , spiders , amphibians and small reptiles . Coua caerulea seems to feed mainly on small lizards.
Enemies
The fossa ( Cryptoprocta ferox ), the Madagascar harrier ( Polyboroides radiatus ) and the Madagascar goshawk ( Accipiter henstii ) are among the proven natural enemies of the silkworms . Most of the birds are killed by humans, who hunt down silky cuckoos with snares and traps for consumption.
Reproduction
Silkworms are not breeding parasites.
Systematics
Traditionally, the silk cuckoos were classified as a separate subfamily Couinae. Since 1997, however, they are together with Asian cuckoo species in the subfamily colored beak cuckoos asked (Phaenicophaeinae) that the tribes is divided Couini for coua and Phaenicophaeini for Asian relatives. Phylogenetic studies have confirmed this relationship. They also showed that the silkworms are a monophyletic group, which in turn consists of two clades : one that includes the tree-dwelling species Coua caerulea and Coua cristata , and another that includes the large, ground-dwelling species Coua cursor , Coua serriana , Coua reynaudii and Coua ruficeps count. (Only six out of nine species were examined).
Today there are nine species left alive. One species became extinct in the 19th century and a subspecies at the end of the 20th century. There are also two known species that became extinct in prehistoric times.
- Blue silk cuckoo ( Coua caerulea ( Linnaeus , 1766))
- Coquerel's silk cuckoo ( Coua coquereli Grandidier A. , 1867)
- Pointed-head silk cuckoo ( Coua cristata ( Linnaeus , 1766))
- Yellow-throated silk cuckoo ( Coua cursor Grandidier A. , 1867)
- † Delalande silk cuckoo ( Coua delalandei Temminck , 1827) (extinct in the 19th century)
- Giant silk cuckoo ( Coua gigas ( Boddaert , 1783))
- Red-forehead silk cuckoo ( Coua reynaudii Pucheran , 1845)
- White-throated silk cuckoo ( Coua ruficeps Gray, GR , 1846)
- Red-breasted cuckoo ( Coua serriana Pucheran , 1845)
- Broad-headed silk cuckoo ( Coua verreauxi Grandidier A. , 1867)
- † Coua primaeva Milne-Edwards & Grandidier , 1895
- † Coua berthae Goodman & Ravoavy , 1993
literature
- SM Goodman, L. Wilmé: Cuculiformes Coua spp., Ccouas. In: Steven M. Goodman, Jonathan P. Benstead, Harald Schütz: The Natural History of Madagascar. University of Chicago Press, ISBN 022-630307-1 .
