Invertebrates
Arrow Crab.
A spindly, spider-like reef crab with a pointed nose and long legs — an oddball scavenger that hunts bristleworms and leftovers. Reef-safe with caution (it may bother small inverts or corals); give it rockwork and a 30-gallon-plus tank.
We keep this species at our Erie store. Come and see it in the tanks, or call (814) 456-9445 and ask what we have in right now.
Sea Cave keeps this species. You will find these in the tanks at 660 East 14th Street in Erie. We never ship live animals.
- Condition
- new
- Fulfillment
- Local pickup — Erie, PA
We never ship fish, coral, or invertebrates — every animal here is one you meet in person. Each one is acclimated and health-checked in-house before it goes out into the display tanks. This is a species we keep, and what is swimming on any given day changes with the deliveries, so please call (814) 456-9445 before you drive in.
Care at a glance
What to know before you take one home.
- Care level
- Intermediate
- Temperament
- Semi aggressive
- Community
- Semi community
- Adult size
- 6"
- Min tank size
- 30 gallons
- Diet
- Carnivore
- Scientific name
- Stenorhynchus seticornis
Good tank mates
A spider-like reef scavenger that is reef-safe with caution and best kept with fast, alert tankmates rather than anything small and slow. It will catch and eat small ornamental shrimp, tiny fish, and sometimes pick at sessile inverts, so avoid housing it with pricey cleaner shrimp, tiny gobies, or anything it can corner. One arrow crab per tank is wise, since they can be aggressive toward each other, and it generally coexists with larger active fish that can stay out of its reach.
Good to know
The arrow crab's body is shaped like a tiny dart with extremely long, jointed legs that can span many times the width of its compact triangular shell, giving it a daddy-longlegs look underwater.
What is in the tanks and each animal's temperament vary — call (814) 456-9445 for pairing advice.
Good tankmates
Plays well with.
Species we’d keep in the same tank, with why each pairing works. What is in the tanks and each animal’s temperament vary — call (814) 456-9445 for advice on pairing.
New to stocking a tank? Read our guide on which fish live together.
Yellow Tang
Yellow Tangs reach 7-8 inches and are fast, active water-column swimmers that a benthic arrow crab cannot realistically threaten. Multiple sources including Aquarium Source and other published care guides confirm tangs are appropriate companions, and the size and speed differential is large enough that the pairing is not contingent on careful feeding management.
- L
Long-spined Sea Urchin
A peer-reviewed study (Virgin Islands, 2002-2003) documented arrow crabs actively sheltering among Diadema antillarum spines in the wild — a true commensal relationship in which the crab gains predation cover and the urchin is unaffected. Neither species has documented aggression toward the other.
Visit the store
660 East 14th Street,
Erie, PA.
Mon–Fri 12–6 · Sat 11–4 · Sun closed. Call ahead on livestock — what's on the floor rotates.