A Lobster by any other name
Our lobster, Homarus americanus, the American lobster, can be found from the Canadian Maritimes down to North Carolina, about 1300 miles to the south, but it is most abundant in Maine waters. (In fact it is so closely identified with Maine that Canadian lobsters being transported by truck through Maine are frequently passed off as "Maine lobsters" by the time they've crossed into New Hampshire.) The "Maine" or "American" lobster is a crustacean with two strong claws: a big-toothed crusher claw for pulverizing shells and a finer-edged ripper claw resembling a steak knife, for tearing soft flesh. (A lobster which carries its crusher claw on the right is a "right-handed" lobster.)
Of the 30 or so types of clawed lobsters worldwide, the American lobster most closely resembles its European cousin, Homarus gammarus, though the western Atlantic crustacean has more robust tearing and crushing claws. In France this lobster is called homard; in Germany, Denmark, Sweden, and Norway, it is a hummer.
The clawless spiny lobster, Panulirus argus, of more southerly waters, is a distant relation of the American lobster. "Lobster tail" comes from any of the 45 species of spiny lobsters of the Palinuridae family. Sometimes called crayfish, crawfish, rock lobster, or langouste, this lobster has a spine-studded shell and long antennae but no large front claws. Instead, the heavily-armored antennae can inflict a tearing wound when the lobster thrashes them whip-like against an opponent.
Unlike the American lobster, spiny lobsters seem to enjoy each other's company and often share their dens in coral reefs. They may warn other lobsters of danger with loud rasping sounds they make by rubbing the base of their antennae against serrated ridges below their eyes.
One of the strangest sights reported by fishermen and divers is the "lobster march." Hundreds, sometimes thousands, of spiny lobsters form columns of as many as 60 lobsters to migrate en masse, often after a storm. Are they migrating to their breeding grounds, seeking warmer water, or searching for a new food supply? Why they march is still a mystery.
The slipper or shovel-nose lobster looks like a crustacean with a flattened face. It is sometimes hard to tell the front from the rear of this lobster with its broad, flat body and very short antennae. Slipper lobsters are harvested in shallow, tropical waters from muddy bottoms, but they are not as highly sought after as other lobsters.
The freshwater crayfish, crawfish, or crawdad resembles a miniature lobster. Its color may range from pink to orange to dark blue. In the gluttonous days of the ancient Roman Empire, crayfish were kept well-fed in large earthenware pots in preparation for royal feasts. The ancient Romans knew then what we have come to appreciate over the past 150 years: lobsters, by any name, taste delicious.
Less famous crustaceans
Lobsters are crustaceans and members of the Arthropod phylum. Crustaceans are characterized by hard shells and jointed appendages. Other crustaceans that may be familiar include shrimp, green crabs, rock crabs, spider crabs, and barnacles.