There are two types of hermit crabs (marine and terrestrial), but they can’t live together. Terrestrial hermit crabs can’t breathe underwater, and aquatic hermit crabs can’t breathe on dry land.
The Caribbean hermit crab is the most popular terrestrial hermit crab, often known as the Purple Pincher or the Ecuadorian hermit crab. Dwarf hermit crabs, especially the Blue-Legged species, are the most common pet marine hermit crabs.
Hermit crabs make rewarding pets, but you must understand the differences between species to care for them. Only pair different hermit crab species if you’re familiar with their unique needs.
With over 800 known species of hermit crabs worldwide, you’d think pet owners would have their pick. In reality, only a small number of hermit crab species are kept as pets in captivity.
How Many Different Types of Pet Hermit Crabs are There?
According to Current Biology, there are over 800 species of hermit crabs.
There are likely many more. New species are constantly discovered, and as most hermit crabs live underwater, many have evaded human detection.
We must divide them into marine or terrestrial categories. As these identities suggest, marine hermit crabs live underwater in an aquarium, while terrestrial hermit crabs live on dry land.
Although so many species of hermit crab exist in the world, comparatively few are kept in homes as domesticated pets. Hermit crabs often struggle with life in captivity, and only a handful of species have been known to successfully make the transition.
Should I Get Terrestrial or Marine Hermit Crabs?
Forget anything you have heard about hermit crabs being disposable pets with a short life expectancy, as they can live up to 30 years in captivity under the right conditions.
Land-based hermit crabs are easily stressed, so you’ll need to work to provide the right living environment. If you do, you’ll be rewarded with pets with lots of personality and entertainment value.
Marine hermit crabs remain underwater all day, so they could be considered higher maintenance. However, they make good additions to an existing aquarium.
Pros and Cons of Terrestrial Hermit Crabs
If you’re considering bringing land-based hermit crabs into your home, consider these pros and cons:
| Advantages | Disadvantages |
| Lots of fun to observe – terrestrial hermit crabs love to play, climb and burrow. | Terrestrial hermit crabs have very particular needs and die in inappropriate conditions. |
| Quiet pets – hermit crabs barely make a noise apart from the occasional chirp. | Primarily nocturnal. If you have children, they’re unlikely to see their pets much. |
| You’ll need to spot-clean a habitat daily, but hermit crabs are relatively hygienic. | Tend to be quite shy around humans, as it takes a while to earn a hermit crab’s trust. |
| Cheap and easy to feed. As natural scavengers, hermit crabs will eat anything. | Can occasionally come into conflict over shells, territory, or colony alpha status. |
Only adopt terrestrial hermit crabs if you have the time and patience to care for them appropriately. These small animals are easily stressed and require a careful, empathetic owner.
Pros and Cons of Marine Hermit Crabs
Some people prefer to focus on water-dwelling hermit crabs. As with terrestrial hermit crabs, there are pros and cons to caring for these species:
| Advantages | Disadvantages |
| Marine hermit crabs like to eat algae, so they’ll keep a fish tank clean. | They can’t leave water for long, as you’ll need to permanently keep them in an aquarium. |
| No smell to worry about as long as you periodically change the aquarium water. | Maintaining an aquarium can be costly, as you’ll use much more energy. |
| They’re more docile than terrestrial crabs and will get along with each other. | May bully and eat sea snails to steal their shells. |
| According to Crustaceana, marine hermit crabs are less fussy about shell changes. | Prone to clumsiness, so you may need to regularly clean or change the water. |
Marine hermit crabs can be a nice addition to a tank if you already have aquatic pets, such as fish or turtles. Ensure the water conditions these animals need match those of your pets.
What are the Most Popular Species of Terrestrial Hermit Crab?
Hermit crabs are rarely sold in pet stores, almost exclusively purchased from seafront gift stores on vacation or over the internet.
If you’re buying a hermit crab from a gift shop, ensure it has not been mistreated. Sadly, many hermit crabs live in substandard conditions in these shopfronts. Look for a hermit crab that meets these criteria.
- Has all 10 legs intact, including the large and small claws.
- Displays an active, bright-eyed, and curious demeanor – inactive hermit crabs may be deeply stressed and unlikely to survive captivity.
- Housed in a pure, unpainted shell. Decorated shells can kill hermit crabs.
- Doesn’t smell, especially a fishy aroma.
If you’re keeping terrestrial hermit crabs, your pets will be one of the following species.
Caribbean Hermit Crab, aka the Purple Pincher (Coenobita clypeatus)
The Purple Pincher, nicknamed for its distinctive large cheliped, is the most popular pet hermit crab worldwide. Growing to around 3.5cm and displaying comparatively hardy characteristics, this is the ideal pet hermit crab for a first-time owner.
Ecuadorian Hermit Crab (Coenobita compressus)
Ecuadorian hermit crabs are usually tiny, rarely exceeding 12mm in size, and look slightly different from other hermit crabs. You can identify an Ecuadorian by its wider body and long eye stalks.
Ecuadorians are the best choice if you’re looking for an active and adventurous colony of hermit crabs. This species tends to be curious and excitable, but they can be reluctant to change shells, often retaining the same vessel after molting.
Strawberry Hermit Crab (Coenobita Perlatus)
Named for its bright red coloring, the Strawberry hermit crab is beautiful. Strawberry hermit crabs must enjoy a constant high temperature and need more space and access to water than others.
Ensure you feed a Strawberry hermit crab a diet rich in carotenes. If this hermit crab doesn’t receive enough pigmentation in its food, its exoskeleton will quickly fade and become washed out.
Cavipe Hermit Crab, aka Cavvie (Coenobita cavipes)
Native to Asia and Africa, Cavvies are brown or blue, with deep red or orange eye stalks and feelers.
They rarely grow any larger than 1.5cm, and while they’re often docile, this breed of hermit crab can be prone to cannibalism. Ensure your Cavvies are fed regularly and enjoy a varied diet.
While all hermit crabs love to climb, cavvies are arguably the most inclined to indulge in this behavior. As per Marine Ecology Progress Series, wild cavvies often live in mangrove trees and only put their feet on the ground to scavenge for food.
Rugosus Hermit Crab, aka Ruggie (Coenobita rugosus)
Ruggies look similar to Ecuadorian hermit crabs, although they often grow much bigger, typically peaking at around 6cm. They also have a distinctive large claw that looks like it contains stitches, and these hermit crabs are among the hairiest.
Ruggie hermit crabs are active, so consider this when choosing a habitat. As these hermit crabs are larger, they’ll likely need a bigger tank to ensure that all animals have territory to call their own.
What are the Most Popular Species of Marine Hermit Crab?
Marine hermit crabs are even more specialized than their terrestrial counterparts. You may find them for sale in an exotic pet store specializing in fish and other aquatic pets.
Dwarf Hermit Crab (Clibanarius sp)
Tiny dwarf crabs are available in a range of colors. Hailing from the Caribbean, they peak in size at 2.5cm. They’re docile, getting along with other hermit crabs and keeping out of the way of fish in a tank.
The Blue-Legged hermit crab is the most commonplace breed of this species, but others are available. You should adopt multiple dwarf hermit crabs to keep each other company. Mixing and matching colors will give you some strikingly ornamental pets.
Polka Dot Hermit Crab (Phimochirus operculatus)
This hermit crab can be fascinating to watch, as it’s among the most active and fastest-moving marine hermit crabs. It is common to find the Polka Dot hermit crab zooming around the floor of an aquarium.
Polka Dot hermit crabs rarely grow any larger than 2.5cm, so do not pair them with aggressive or gluttonous fish lest they end up as a snack. This hermit crab can be harder to source in the U.S., and prices vary wildly from $5 to $40.
Electric Orange Hermit Crab (Elassochirus gilli)
This bright and striking hermit crab hails from Hawaii, so it’s among the few American natives on our list. This is a popular hermit crab for fish owners looking for a clean-up crew for an aquarium. No algae will be safe from this breed.
The Electric Orange hermit crab also loves to sift and dig through the substrate at the bottom of a tank. This can ensure that your aquarium is regularly aerated. It is among the more delicate breeds of marine hermit crab, though.
Halloween Hermit Crab (Ciliopagurus strigatus)
Among the largest marine hermit crabs at 5cm, the Halloween hermit crab takes its name from its coloring – the stripy orange-and-black legs will instantly remind you of October. This hermit crab is a little rarer and more expensive, typically costing over $15.
As the Halloween hermit crab is on the bigger side, avoid keeping more than two or three together. Be mindful that this breed can also be a little lumbering and may damage corals or decorations in an aquarium.
Scarlet Reef Hermit Crab (Paguristies cadenati)
Arguably the most docile hermit crab of all, this species takes its name from its striking, fire truck-red coloring. The distinctive yellow eye stalks of the Scarlet Reef Hermit Crab add a little more aesthetic personality.
Many fish owners apply this species to an aquarium as it is one of the most greedy breeds of hermit crab around when it comes to consuming algae. It’s a little bigger than some marine hermit crabs at roughly 3cm, but the Scarlet Reef hermit crab will not get in the way.
Can Different Species of Hermit Crabs Live Together?
Marine hermit crabs can never live on dry land with terrestrial hermit crabs and vice versa. Your land-based hermit crabs will drown within an hour if placed in an aquarium, while the marine hermit crabs suffocate if removed from the water for too long.
You can mix and match land or marine hermit crabs in the same environment, within reason. Be mindful of size differences. While most hermit crabs are docile, larger breeds may injure smaller tankmates.
It’s easier to pair marine hermit crabs with other animals, such as fish or turtles. Terrestrial hermit crabs can live with some reptile species, but overall they’re safest with their own kind.
