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Hermit Crab Hydroid Research
Cn-110 PINK HYDROID, Eudendrium carneum
A handsome plumed hydroid with orange gonophores. It grows explosively over floating docks and wharf pilings in the spring and begins to die off in cold weather. By the dead of winter, only small tufts with a few polyps can be found. Under the dissecting scope, you can watch the feeding polyps stretch out and slowly grasp at bits of food. Nudibranchs glide over the stems along with flexing, bobbing skeleton shrimp, also snails, flatworms, etc., which are protected by the stinging polyp forests. Eudendrium is excellent for demonstrating tissue differentiation of polyps and stolons. Specimens will produce planula larvae if kept overnight in a dish of seawater. Size: 10-20 cm or larger.
Small Collection: $20.00
Medium Collection: $38.00
Large Collection: $65.00
Cn-120 HERMIT CRAB HYDROID, Hydractinia synbiolongicarus
A small pink hydroid that encrusts living hermit crabs and the gastropod, Cantharus cancellarius. Polyps display an elaborate variety of growth forms, including nutritive, generative, and defensive zooids. A similar hydroid, Podocoryne carnea, may also be present. Both species take advantage of their mobile substrates by feeding on floating remnants of food or catching food particles stirred up by the host’s passage. Size of shell: 1-3 cm.
Cn-140 FERN HYDROID, Pennaria tiarella
It is a bright pink hydroid with fern-like branchings that prefers higher salinity waters. Medusa buds develop along sides of hydranths. The knobby tentacles of Pennaria possess highly developed nematocysts that make them sting like fire when handled. Yet under a dissecting scope, their beauty is unsurpassed. Available June through October.
Cn-150 CROSS JELLY HYDROMEDUSA, Nemopsis bachei
Of the family Bougainvillidae, it exhibits rapid pulsating movements across the aquarium. Crystal clear except for the white gonad cross on its umbrella, it’s hard to believe that an insignificant hydroid parent gives rise to such a relatively large, delightful medusa. Available December through April. Size: 0.5 cm.