Homarus is a genus of lobsters, which include the common and commercially significant species Homarus americanus (the American lobster) and Homarus gammarus (the European lobster). The Cape lobster, which was formerly in this genus as H. capensis, was moved in 1995 to the new genus Homarinus.
Description
Homarus is one of three extant genera of clawed lobsters to show dimorphism between claws – a specialisation into a crushing claw and a cutting claw. The other similar genera are Nephrops, which is much more slender, and has grooves along the claws and the abdomen, and Homarinus, the Cape lobster from South Africa, which is even smaller, and has hairy claws.
While analyses of morphology suggest a close relationship between Homarinus and Homarus, molecular analyses using mitochondrial DNA reveal that they are not sister taxa. Both genera lack ornamentation such as spines and carinae, but are thought to have reached that state independently, through convergent evolution. which stretches back to the Cretaceous, but only two species survive. These two species, the American lobster and the European lobster, are very similar and may have speciated as recently as the Pleistocene, during climatic fluctuations.
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! Image !! Scientific name !! Common name!! Description!! Distribution
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|150px || Homarus gammarus || European lobster or common lobster || may grow to a length of and a mass of , and bears a conspicuous pair of claws. Homarus gammarus is a highly esteemed food, and is widely caught using lobster pots,
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|150px || Homarus americanus || Atlantic lobster, Canadian lobster, true lobster, northern lobster, Canadian Reds, or Maine lobster. || commonly ranges from in length and in weight, but have been known to reach lengths of and weigh as much as or more, making this the heaviest marine crustacean in the world. An average adult is about long and weighs . They are:
- Homarus brittonestris <small>Stenzel, 1945</small> – lower Turonian
- Homarus davisi <small>Stenzel, 1945</small> – lower Turonian
- Homarus fami <small>Garassino, Pasini, Nyborg, Haggart, 2021</small> – Albian
- Homarus lehmanni <small>Haas, 1889</small> – Rupelian
- Homarus mickelsoni <small>(Bishop, 1985)</small> – lower Campanian
- Homarus morrisi <small>Quayle, 1987</small> – Eocene
- Homarus neptunianus <small>Polkowsky, 2004</small> – Oligocene
- Homarus travisensis <small>Stenzel, 1945</small> – middle Albian
Distribution
The two extant species of Homarus are both found in the North Atlantic Ocean. H. americanus is found from Labrador to North Carolina in the western North Atlantic, while H. gammarus is found from Arctic Norway to Morocco, including the British Isles and the Mediterranean Sea.