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'
Nephilengys upon by the spider-eating jumping spider "Portia". At least some species shake their bodies vigorously when touched. Nephilengys Nephilengys is a genus of tropical spiders of the family Araneidae, consisting of two currently described species. (The genus was formerly placed in the Nephilidae and Tetragnathidae.) The genus "Nephilingis" has been split off from this genus. Both genera have been called hermit spiders from the habit staying in their retreats during the day; the name eunuch spiders has been used for "Nephilengys" alone. Males may sever parts of their palpal bulbs after copulation. Females are from 10 mm to 28 mm