The Wallcreeper is intermediate in its morphology between the nuthatches and the treecreepers, but its appearance, the texture of its plumage, and the shape and pattern of its tail suggest that it is closer to the former taxon. It is occasionally placed in a separate family, the Tichodromadidae.
The Nuthatch Vanga of Madagascar and the sitellas from Australia and New Guinea were once placed in the family Sittidae, because of similarities in appearance and lifestyle to the nuthatches, but they are not closely related, the resemblances arising from convergent evolution to fill an ecological niche.
The Wallcreeper is an insectivore, which feeds on invertebrates, primarily insects and spiders gleaned from the rock face. Invertebrates are also a major part of the diet for nuthatches, especially during the breeding season, but most species also eat seeds at least during the winter, when invertebrates are less readily available. Larger food items, such as big insects, snails, acorns or seeds may be wedged into cracks and hacked with the nuthatches's strong bill, this of course being the behaviour which gives that subfamily group its name. The nuthatches all store food, usually seeds, which may be pushed into crevices or into the ground, hidden under small stones, or tucked behind bark flakes; the rock nuthatches will also wedge snails into suitable crevices for consumption in times of need. Caches are recovered by memory, and can be retrieved as long as 98 days after being stored. In one study of European Nuthatches birds refrained from using their caches during benign conditions in order to save them for harsher conditions.
The Wallcreeper and most nuthatches have large populations and extensive geographical ranges, and present few conservation problems,
A few of the more restricted nuthatch species are threatened by deforestation.
Orthoskrjabinia rostellata (Cestoidea: Dilepididae), from the brown-headed nuthatch, Sitta pusilla (Passeriformes: Sittidae), from Northeastern Texas. (General Notes).
May 01, 2003; The dilepidid tapeworm, Anonchotaenia rostellata (Rodgers 1941) was described from 13 specimens taken from the small intestine of...