Freshwater





Insects are almost completely lacking in the marine environment. I recall something about saltwater having a very bad effect on their lungless respiratory system ( although this does not affect spiders. ) Insects are quite common in freshwater environments though, both as larvae and adults. A little digging can turn up myriad types, but be careful, some of them can bite very painfully.






Hydroids

Masses of hydroids adorn many of the offshore wrecks, mixed in with anemones, sponges, mussels, coral, and algae. Hydroids are the most primitive Cnidarians, closely related to Hydromedusae, and display the most even split between the sessile polyp stages and free-swimming medusa stages, which are quite small and common.

The common Pink-Hearted Hydroid Tubularia spp generally grows in rounded tufts up to 6" across. Siphonophores are free-living hydroids that are often highly venomous, although most attached forms are harmless to humans.