Diastataxia

Under Diastataxie refers to a gap in the ranking of the secondaries of a bird's wing.

In this case, the gap means that the transverse rows, which are composed of flight feathers and a set of associated upper and lower cover springs, have been supplemented by a row between the arm wings 4 and 5. But since the big swing spring is missing, one speaks of a gap. If this addition to the series is missing, one speaks of eutaxia .

When the wing is folded up, the flight feathers including the cover springs are pushed over one another. Because of the sometimes required more wing folding in some groups of birds, the diastataxic gap developed for relief.

The diastataxic fletching is rather the exception. It affects the goose birds (Anseriformes), the flamingos (Phoenicopteriformes), the birds of prey (Accipiteriformes) and the loons (Gaviiformes) completely. Among the hen birds (Galliformes), the waders (Charadriiformes) and the pigeons (Columbiformes) there are species with both eutaxic and diastataxic fletching.

literature

• Wolf-Dieter Busching: Handbook of the plumage of European birds. AULA-Verlag, Wiesbaden 1997, ISBN 3-89104-570-0 .