Classification
It is firmly established that hermit crabs are more closely related to squat lobsters and porcelain crabs than they are to true crabs (Brachyura). However, the relationship of king crabs to the rest of Paguroidea is a highly contentious topic. Many studies based 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 Lithodidae (king crabs) should be placed with Hapalogastridae in a separate superfamily Lithodoidea. Six families are formally recognized in the superfamily Paguroidea, containing around 1100 species in total in 120 genera.
- Coenobitidae – 2 genera: terrestrial hermit crabs and the coconut crab
- Diogenidae – 20 genera of "left-handed hermit crabs"
- Paguridae – 76 genera
- Parapaguridae – 10 genera
- Parapylochelidae – 2 genera
- Pylochelidae – 9 genera of "symmetrical hermit crabs"
- Pylojacquesidae – 2 genera
Read more about this topic: Hermit Crab