浅蜊 (あさり, asari) – Manila clam (Ruditapes philippinarum)

赤貝 (あかがい, akagai) – blood clam (Scapharca broughtonii); ark shell

蛸 (たこ, tako) – octopus

海獺 (らっこ, rakko) – sea otter (Enhydra lutris)

鰻 (うなぎ, unagi) – eel (esp. the Japanese eel, Anguilla japonica)

平目 (ひらめ, hirame)
1. flounder (esp. the large-tooth flounders of family Paralichthyidae, but also lefteye flounders of family Bothidae)
2. bastard halibut; olive flounder (Paralichthys olivaceus)

鰈 (かれい, karei) – righteye flounder (any fish of family Pleuronectidae)

A mnemonic used in Japanese to differentiate between 平目 and 鰈 is 左ヒラメに右カレイ or ‘hidari hirami ni migi karei’, meaning left for hirame and right for karei. It kind of rhythms and may help you remember which is which. You’ll also notice that the number of syllabus for hidari and hirame is the same, as with migi and karei. Now all you have to do is remember whether ‘hidari’ and ‘migi’ is left or right. 😛

鯰 (なまず, namazu) – catfish (esp. the Amur catfish, Silurus asotus)

Interestingly, a giant catfish is believed to be the cause of earthquakes in Japanese myths.

真鯛 (まだい, madai) – tai (species of red Pacific sea bream, Pagrus major)

伊勢海老 (いせえび, iseebi) – spiny lobster (esp. Japanese spiny lobster, Panulirus japonicus)