Hermit crab on physical characteristics, genetic information, and combined data, support the longstanding hypothesis that the king crabs in the family Lithodidae are derived hermit crabs and should be classified as a family within Paguroidea. Other researchers have challenged this, asserting that the Lithodidae (king crabs) should be placed with the Hapalogastridae in a separate superfamily Lithodoidea. Six families are formally recognized in the superfamily Paguroidea, containing around 1100 species in total in 120 genera. The fossil record of "in situ" hermit crabs using gastropod shells stretches back to the Late Cretaceous. Before that time, at least some hermit crabs used ammonites'
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.