Hermit crab wood and stone are used by some species). The tip of the hermit crab's abdomen is adapted to clasp strongly onto the columella of the snail shell. Most hermit crabs are nocturnal. Hermit crabs can be divided into two groups: As hermit crabs grow, they require larger shells. Since suitable intact gastropod shells are sometimes a limited resource, vigorous competition often occurs among hermit crabs for shells. The availability of empty shells at any given place depends on the relative abundance of gastropods and hermit crabs, matched for size. An equally important issue is the population of organisms that prey
Cinnamon-throated hermit analysis by Hinkelmann where it merely is considered the male plumage of "P. nattereri". But as it seems, the Maranhao hermit only occurs in the northern part of the range of "P. nattereri", and as the two have different voices they seem to warrant recognition as distinct species "P. maranhaoensis". It is pending of confirmation by molecular work. Cinnamon-throated hermit The cinnamon-throated hermit ("Phaethornis nattereri") is a species in the hummingbird family, Trochilidae. It is found in a broad dry to semi-humid belt along the southern edge of the Amazon Rainforest from far north-eastern Bolivia north-east to Maranhão in Brazil.