Hermit crab shells instead, as shown by a specimen of "Palaeopagurus vandenengeli" from the Speeton Clay, Yorkshire, UK from the Lower Cretaceous. Hermit crab Hermit crabs are decapod crustaceans of the superfamily Paguroidea. Most of the approximately 1,110 species possess an asymmetrical abdomen that is concealed in a scavenged mollusc shell carried around by the hermit crab. Most species have long, spirally curved abdomens, which are soft, unlike the hard, calcified abdomens seen in related crustaceans. The vulnerable abdomen is protected from predators by a salvaged empty seashell carried by the hermit crab, into which its whole body can retract. Most frequently,
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