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'
Wall spider called "O. annulipes"). One species of interest is Oecobius civitas. When a spider enters the home of another spider, rather than defend itself, the resident leaves to find another one. Wall spider Wall spider is the common name for members of the genus Oecobius. The members of these several species are all very small spiders that make small flat webs over crevices in walls and in similar spaces. They possess an organ called a cribellum, which is a kind of comb-like device used to separate fibers of silk drawn from its spinnerets into many extremely fine fibers. Those fibers are