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
Hermit (hummingbird) notably SACC, which consider both "T. niger" and "T. leucurus" as valid species. Additionally, Mallet-Rodrigues (2006) suggested the taxon "loehkeni" should be considered a valid species, the bronze-tailed barbthroat. Three additional species, the tooth-billed hummingbird ("Androdon aequatorialis"), the green-fronted lancebill ("Doryfera ludovicae") and the blue-fronted lancebill ("D. johannae"), have been included in this subfamily in the past, but are now placed in "Trochilinae". Hermit (hummingbird) The hermits are tropical and subtropical hummingbirds in the subfamily Phaethornithinae, comprising 30–40 species in six genera. They occur from southern Mexico, through Central America, to South America as far south as northern Argentina. Their