| Common Name | Scientific Name | Notes |
| Class Gastropoda – Limpets, Snails and Nudibranchs | | |
| Family Acmaeidae – Plate Limpets | | |
| Atlantic Plate Limpet | Testudinalia testudinalis | |
| Family Trochidae – Top Shells | | |
| Obscure Solarelle | Solariella obscura | very rare; one found in 1958. |
| Family Lacunidae – Lacuna Shells | | |
| Common Northern Lacuna | Lacuna vincta | |
| Family Calyptraeidae – Cup-and-Saucer Limpets | | |
| Common Atlantic Slipper | Crepidula fornicata | on Nomans Land |
| Convex Slipper | Crepidula convexa | |
| Eastern White Slipper | Crepidula plana | also on Nomans Land |
| Striate Cup-and-Saucer Limpet | Crucibulum striatum | very rare |
| Family Rissoidae – Cingulas | | |
| Pointed Cingula | Cingula aculeus | uncommon to rare |
| Chestnut Alvania | Alvania castanea | |
| Carinate Alvania | Alvania pelagica | |
| Family Littorinidae - Periwinkles | | |
| Smooth Periwinkle | Littorina obtusata | also on Nomans Land |
| Northern Rough Periwinkle | Littorina saxatilis | |
| Common Periwinkle | Littorina littorea | also on Nomans Land |
| Marsh Periwinkle | Littorina irrorata | uncommon |
| Family Triforidae - Triforas | | |
| Black-lined Trifora | Trifora nigrocincta | uncommon |
| Family Janthinidae – Purple Snails | | |
| Common Purple Sea Snail | Janthina janthina | rare |
| Globe Purple Sea Snail | Janthina globosa | very rare; two found in 1959 |
| Family Aporrhaidae – Pelican’s Foot | | |
| American Pelican’s Foot | Aporrhais occidentalis | very rare; one found in 1960 |
| Family Naticidae – Moon Shells | | |
| Common Northern Moon Shell | Lunatia heros | also on Nomans Land |
| Shark Eye | Polinices duplicatus | |
| Immaculate Moon Shell | Polinices immaculatus | rare |
| Spotted Northern Moon Shell | Lunatia triseriata | uncommon; on Nomans Land |
| Southern Miniature Natica | Natica pusilla | uncommon |
| Arctic Natica | Natica clausa | very rare; found 1873 |
| Family Buccinidae - Whelks | | |
| Waved Whelk | Buccinum undatum | uncommon; on Nomans Land |
| Pygmy Colus | Colus pygmaea | very local and rare |
| Northern Colus | Colus islandicus | rare |
| Brown-corded Neptune | Neptunea decemcostata | uncommon |
| Family Melongenidae – Crown Conchs | | |
| Knobbed Whelk | Busycon carica | on Nomans Land |
| Channeled Whelk | Busycon canaliculatum | |
| Family Muricidae – Drills and Rock Shells | | |
| Atlantic Oyster Drill | Urosalpinx cinereal | also on Nomans Land |
| Thick-lipped Drill | Eupleura caudata | |
| Atlantic Dogwinkle | Nucella lapillus | on Nomans Land |
| Family Nassariidae – Mud Snails | | |
| New England Nassa | Nassarius trivittatus | on Nomans Land |
| Common Eastern Nassa | Nassarius vibex | rare |
| Eastern Mud Nassa | Nassarius obsoletus | |
| Family Columbellidae – Dove Shells | | |
| Well-ribbed Dove Shell | Anachis translirata | also on Nomans Land |
| Greedy Dove Shell | Anachis avara | |
| Lunar Dove Shell | Mitrella lunata | |
| Family Epitoniidae - Wentletraps | | |
| Greenland Wentletrap | Epitonium greenlandicum | uncommon |
| Brown-banded Wentletrap | Epitonium rupicola | rare |
| Champion’s Wentletrap | Epitonium championi | |
| Family Turritellidae – Worm Shells | | |
| Spiral Worm Shell | Vermicularia spirata | |
| Alternate Bittium | Bittium alternatum | |
| Family Cerithiidae – Cerith Shells | | |
| Adam’s Miniature Cerith | Seila adamsi | rare |
| Awl Miniature Cerith | Cerithiopsis subulata | rare |
| Green’s Miniature Cerith | Cerithiopsis greeni | rare |
| Brown Sargassum Snail | Litiopa melanostoma | rare; only on Sargassum weed |
| Family Turridae – Mangelia Shells | | |
| Plicose Mangelia | Mangelia plicosa | uncommon |
| Waxy Mangelia | Mangelia cerina | uncommon |
| Violet Mangelia | Curitoma violacea | uncommon |
| Lora Turret | Propebela lora | |
| Harpshell Turret | Proebela harpularia | very rare; found off Gay Head 1871, 1880, 1881 |
| Family Pyramidellidae – Odostomes and allies | | |
| Fat Odostome | Odostomia gibbosa | |
| Half-smooth Odostome | Odostomia seminuda | |
| Double-sutured Odostome | Odostomia bisuturalis | |
| Bush’s Odostome | Odostomia bushiana | rare |
| Three-lined Odostome | Odostomia trifida | uncommon |
| Snowy Turbonille | Turbonilla nivea | rare |
| Verrill’s Turbonille | Turbonilla verrilli | rare; the type specimen taken at Martha’s Vineyard. |
| Elegant Turbonille | Turbonilla elegantula | very rare |
| Varied Turbonille | Turbonilla stricta | uncommon |
| Carolina Turbonille | Turbonilla caroliniana | uncommon |
| Interrupted Turbonille | Turbonilla interrupta | |
| Mighel’s Turbonille | Turbonilla mighelsi | rare |
| Long Pyram | Sayella producta | rare |
| Stimpson’s Pyram | Stilifer stimpsoni | rare |
| Olive Mellanella | Mellanella oleacea | |
| Conoidal Eulima | Melanella conoidea | rare |
| Family Amnicolidae – River Dwellers | | |
| Totten’s Hydrobia | Hydrobia totteni | |
| Family Caecidae – Tiny Tubular Snails | | |
| Beautiful Little Caecum | Cuecum pulchellum | |
| Cooper’s Atlantic Caecum | Caecum cooperi | rare |
| Family Acteonidae – Baby-Bubbles | | |
| Adam’s Baby-Bubble | Acteon punctostriatus | very rare; one found c. 1960 |
| Family Atydae – Paper-Bubbles | | |
| Eastern Paper-bubble | Haminoea solitaria | |
| Atlantic Paper-bubble | Haminoea succinea | uncommon to rare |
| Quadrate Paper-bubble | Philine quadrata | |
| Family Retusidae – Barrel-Bubbles | | |
| Channeled Barrel Bubble | Retusa canaliculata | rare |
| Arctic Barrel Bubble | Retusa obtusa | |
| Family Acteocinidae – Barrel-Bubbles | | |
| Brown’s Barrel-Bubble | Cylichna alba | |
| Oryza Barrel-Bubble | Acteocina oryza | rare |
| Family Ellobiidae – Salt Marsh Snails | | |
| Common Salt Marsh Snail | Melampus bidentatus | |
| Family Aplysiidae – Sea-hares | | |
| Willcox’s Sea-hare | Aplysia willcoxi | uncommon; one found in 1968 |
| Family Cymbulidae – Pteropods | | |
| Shoe-shaped Pteropod | Corolla calceola | very rare; found once off Gay Head |
| Family Spiratellidae – Pteropods | | |
| Retrovert Pteropod | Spiratella retroversa | rare; found in late 1800’s and in 1964 |
| Family Plakobranchidae - Sea Slugs | | |
| Eastern Emerald Elysia | Elysia chlorotica | Found in Menemsha Pond (iNaturalist) |
| Family Clionidae – Sea Butterflies | | |
| Naked Sea Butterfly | Clione limacina | |
| Family Cavolinidae – Pteropods | | |
| Three-toothed Cavoline | Cavolina tridentata | rare |
| Straight-needle Pteropod | Creseis acicula | very rare; found in 1871 |
| Family Pleurobranchiidae - Nudibranchs | | |
| Atlantic Pleurobranch | Pleurobranchus tarda | found on Sargassum weed in Vineyard Sound |
| Family Corambidae - Nudibranchs | | |
| Obscure Nudibranch | Corambe obscura | |
| Family Dorididae – Nudibranchs | | |
| White Dorid | Lamellidoris muricata | |
| Family Polyceridae – Nudibranchs | | |
| Rim-backed Nudibranch | Polycera dubia | |
| Family Fionidae – Nudibranchs | | |
| Atlantic Blue Fiona | Fiona pinnata | |
| Family Dotodae – Nudibranchs | | |
| Coronate Doto | Doto coronata | |
| Family Okeniidae – Okenias | | |
| Modest Okenia | Okenia modesta | uncommon and off Nomans Land |
| Family Dendronotidae – Nudibranchs | | |
| Frond Eolis | Dendronotus frondosus | |
| Family Scyllaeidae – Nudibranchs | | |
| Sargassum Nudibranch | Scyllaea pelagica | found on Sargassum weed in Vineyard Sound |
| Family Aeolidiidae – Nudibranchs | | |
| Papillose Eolis | Aeolidia papillosa | |
| Family Tergipedidae – Nudibranchs | | |
| Johnston’s Balloon Eolis | Tergipes despectus | |
| Balloon Eolis | Tenellia adspersa | rare; found in 1881 |
| Family Glaucidae – Nudibranchs | | |
| Blue Glaucus | Glaucus marinus | in ocean off south coast |
| Crested Glaucis | Cratena pilata | rare; found in 1873 |
| Family Flabellinidae - Nudibranchs | | |
| Red-gilled Nudibranch | Flabellina gracilis | |
| Red-gilled Nudibranch | Coryphella verrucosa | |
| Salmon-gilled Nudibranch | Coryphella salmonacea | |
| Dwarf Balloon Eolis | Eubranchus exiguus | |
| Painted Balloon Eolis | Eubranchus pallidus | |
| Class Amphineura – Chitons | | |
| Family Ischnochitonidae - Chitons | | |
| Common Eastern Chiton | Chaetopleura apiculata | |
| Class Scaphopoda – Dentaliums and Tusk Shells | | |
| Family Dentaliidae - Tusks | | |
| Stimpson’s Tusk | Antalis entalis | very rare; one known specimen found c.1940’s |
| Class Pelecypoda – Clams, Oysters, Scallops, etc. | | |
| Family Solemyacidae – Awning Clams | | |
| Atlantic Awning Clam | Solemya velum | |
| Family Arcidae – Ark Shells | | |
| Transverse Ark | Anadara transversa | |
| Blood Ark | Anadara ovalis | uncommon to rare |
| Ponderous Ark | Noetia ponderosa | |
| Family Mytilidae - Mussels | | |
| Blue Mussel | Mytilus edulis | on Nomans Land |
| Black Mussel | Musculus niger | |
| Smooth Mussel | Musculus laevigata | uncommon |
| Northern Horse Mussel | Modiolus modiolus | uncommon; also on Nomans Land |
| Atlantic Ribbed Mussel | Modiolus demissus | also on Nomans Land |
| Glandular Bean Mussel | Crenella glandula | |
| Family Pectinidae - Scallops | | |
| Atlantic Bay Scallop | Aequipecten irradians | on Nomans Land |
| Atlantic Deep Sea Scallop | Placopecten magellanicus | |
| Iceland Scallop | Chlamys islandica | uncommon |
| Family Anomiidae – Jingle Shells | | |
| Common Jingle | Anomia simplex | also on Nomans Land |
| Prickly Jingle | Anomia aculeate | uncommon |
| Family Ostreidae - Oysters | | |
| Eastern Oyster | Crassostrea virginica | |
| Family Crassatellidae – Triangular Shells | | |
| Lindsley’s Crassinella | Crasinella mactracea | uncommon |
| Family Carditidae - Carditas | | |
| Northern Cardita | Venericardia borealis | uncommon; on Nomans Land |
| Family Diplodontidae – Cleft Clams | | |
| Atlantic Cleft Clam | Thyasira trisinuata | uncommon |
| Family Lucinidae – Lucinas | | |
| Northeast Lucina | Lucinoma filosa | |
| Cross-hatched Lucina | Divaricella quadrisulcata | uncommon |
| Family Cardiidae – Cockle Shells | | |
| Morton’s Egg Cockle | Laevicardium mortoni | |
| Northern Dwarf Cockle | Cerastoderma pinnulatum | |
| Family Nuculidae – Nut Clams | | |
| Atlantic Nut Clam | Nucula proxima | |
| Delphinula Nut Clam | Nucula delphinodonta | rare; found off Gay Head |
| Family Nuculanidae - Yoldias | | |
| File Yoldia | Yoldia limatula | uncommon |
| Short Yoldia | Yoldia sapotilla | |
| Family Astartidae - Astartes | | |
| Chestnut Astarte | Astarte castanea | on Nomans Land |
| Waved Astarte | Astarte undata | uncommon |
| Squarish Astarte | Astarte quadrans | |
| Family Pleurophoridae – Black Clams | | |
| Ocean Quahog | Arctica islandica | uncommon on shore |
| Family Veneridae – Venus Clams | | |
| Northern Quahog | Mercenaria mercenaria | on Nomans Land |
| Morrhua Venus | Pitar morrhuana | rare |
| Amethyst Gem Clam | Gemma gemma | |
| Family Leptonidae – Nestler Clams | | |
| Atlantic Flat Lepton | Mysella planulata | |
| Northern Lepton | Mysella bidentata | rare; found in 1875 |
| Eastern Aligena | Aligena elevata | uncommon |
| Family Petricolidae – False Angel Wing | | |
| False Angel Wing | Petricola pholadiformis | |
| Family Pholadidae – Boring Clams and Piddocks | | |
| Fallen Angel Wing | Barnea truncata | uncommon |
| Great Piddock | Zirphaea crispata | rare to very rare |
| Angel Wing | Cyrtopleura costata | uncommon |
| Family Tellinidae - Tellins | | |
| Northern Dwarf Tellin | Tellina agilis | uncommon |
| Delicate Tellin | Tellina tenella | rare |
| Tenta Macoma | Macoma tenta | rare |
| Balthic Macoma | Macoma balthica | uncommon |
| Family Semelidae - Semeles | | |
| Tellin-like Cumingia | Cumingia tellinoides | |
| Family Corbuldae – Basket Clams | | |
| Contracted Corbula | Corbula contracta | rare |
| Family Sanguinolariidae – Long Siphon Clams | | |
| Stout Tagelus | Tagelus plebeius | also on Nomans Land |
| Purplish Tagelus | Tagelus divisus | very rare |
| Family Solenidae – Razor Clams | | |
| Atlantic Razor Clam | Siliqua costata | rare |
| Common Razor Clam | Ensis directus | |
| Green Jackknife Clam | Solen viridis | rare |
| Family Mactridae – Surf Clams | | |
| Stimpson’s Surf Clam | Spisula polynyma | |
| Atlantic Surf Clam | Spisula solidissima | found on Nomans Land |
| Dwarf Surf Clam | Mulinia lateralis | |
| Family Hiatellidae – Saxicaves | | |
| Arctic Saxicave | Hiatella arctica | extremely rare; found once in October 1958 |
| Family Myacidae – Soft-shell Clams | | |
| Soft-shell Clam | Mya arenaria | |
| Family Thraciidae – Thracias | | |
| Conrad’s Thracia | Thracia conradi | |
| Northern Thracia | Thracia septentrionalis | rare |
| Family Periplomatidae – Spoon Clams | | |
| Lea’s Spoon Clam | Periploma leanum | |
| Paper Spoon Clam | Periploma papyratium | |
| Family Mesodesmatidae – Wedge Clams | | |
| Arctic Wedge Clam | Mesodesma arctatum | uncommon |
| Family Teredinidae – Shipworms | | |
| Common Shipworm | Teredo navalis | uncommon; also on Nomans Land |
| Family Lysonidae – Lysonias | | |
| Glassy Lyonsia | Lyonsia hyalina | uncommon |
| Family Pandoridae - Pandoras | | |
| Gould’s Pandora | Pandora gouldiana | uncommon |
| Class Cephalopoda – Squid, Octopus, and Cuttlefish | | |
| Family Spirulidae – Spirulas | | |
| Common Spirula | Spirula spirula | very rare |
| Family Loliginidae – Long-finned Squid | | |
| Atlantic Long-finned Squid | Loligo pealeii | common seasonally |
| Family Ommastrephidae – Short-finned Squid | | |
| Short-finned Squid | Illex illecbrosus | uncommon in Vineyard Sound |
| Family Argonautidae – Nautiluses | | |
| Common Paper Nautilus | Argonauta argo | extremely rare; the northernmost known locality for this tropical species. |
| Family Octopodidae - Octopusses | | |
| Offshore Octopus | Bathypolypus arcticus | uncommon; usually in deep ocean water; a small one found in Menemsha Pond in October 1988. |
| Common Atlantic Octopus | Octopus vulgaris | one taken in Vineyard Sound 1876 |