Univalve Shell ID Guide: Conchs, Whelks, Cones, Helmets & More

Beautiful Seashells

If you have ever walked the beaches along the U.S. Atlantic or the Gulf of Mexico coasts, south to the Caribbean and Central America, and let's not forget the Indo-Pacific regions, all of which are subtropical to tropical, you have likely come across various seashells—lovely and irresistible to pick up!

Univalve Photo Essay

The following photo essay features univalves, otherwise called gastropods or sea snails, which are characterized by a single shell, typically spiraled. I have provided easy-to-follow descriptions for identification as well as some interesting facts and beautiful photographs from a variety of shells in my personal collection of 40+ varieties.

Note: When identifying shells, location is important along with the obvious features such as shape, textures, markings, and color. Size is important as well, but keep in mind that sometimes you may have found a juvenile that hasn't reached full size.

1. Queen Conch Snail

The Queen Conch (pronounced "conk") is a tropical marine mollusk sea snail with a spiral shell that may bear numerous knobs, a long spire, and a flared lip. Conchs, as with all sea snails, have a well-developed head with eyes, tentacles, and a mouth; a broad muscular foot for crawling, and a soft body mass that is protected by their shell.

Big, heavy, and impressive shells house a tasty animal known as the Queen Conch, which may find itself loved out of existence. They are eagerly collected by shell enthusiasts and fisheries alike, but it is a protected species in the U.S. state of Florida. Whether dead or alive, collectors are warned to keep their hands off. Their slow growth rate, occurrence in shallow waters, and late maturation make the Queen Conch particularly susceptible to over-fishing.

How to ID a Queen Conch Snail

Much has been written about this species with its beauty, size, many uses, and popularity. They are the ones you see in the movies of native islanders blowing into to call on the gods, or little kids putting them up to their ears to listen to the call of the ocean.

Look for a sharp apex and thick triangular knobs on the whorls. The outside is brownish yellow with a bright pink opening and lip. Only as adults, the lips of the shell are thick and flared. But their large size may be the best identifying feature.

They feed on algae and other plant material distinguishing them from the carnivorous whelks or helmet sea snails.

• Size: Up to 8-12 in, 15-31 cm; living up to 40 years
• Habitat: Sandy, shallow, warm waters in coral reefs or seagrass beds
• Range: Atlantic coast from Florida, west throughout the entire Gulf of Mexico zone and greater Caribbean tropical zone, and as far south as Venezuela
• Latin name: Strombus gigas

2. Florida Fighting Conch

The Florida Fighting Conch is another favorite among collectors and one of the more common finds along the Atlantic and Gulf of Mexico coastlines.

Look for an attractive thick orange-brown conch with darker brown blotches, sometimes light tan blotches over creamy white. Knobs may be present on larger whorls. The interior is darker brown with a wide, thick lip bearing a distinct indentation near the posterior end and slight ribs.

They eat algae and other tiny marine plants.

• Size: Up to 3-4 in
• Habitat: Sandy and muddy bottoms in shallow water
• Range: North Carolina to Florida, west to Texas
• Latin name: Strombus alatus

3. Dog Conch or Yellow Conch

The Dog Conch or Yellow Conch is from the family Strombidae, the true conchs. Colored golden brown to yellow sometimes with a darker-brown zig-zag pattern. The body is inflated especially at the shoulder, topped with a few spiral grooves and a pointy spire. Has a thick flared outer lip. The interior is white, mature specimens present a metallic gray on the margin of the outer lip.

Although valued as a collectible, is also used as bait because of its heavy "sinkable" weight for fishing nets.

It grazes on algae and detritus (gravel, sand, silt).

Is commonly fished for human consumption.

• Size: Up to 4 in, 10 cm
• Habitat: Sandy bottoms
• Range: Indo-Pacific from India, Australia, north to Japan
• Latin name: Laevistrombus canarium, better known as Strombus canarium

4. Spider Conch

The Spider Conch is in the Strombidae family, the true conchs. It is a very ornamented species with its flared-out lip decorated further with six or seven spiked digits. Males and females differ here with the male showing the three innermost digits shorter and bent towards the posterior, whereas the female demonstrates longer and laterally curved digits. The spikes improve the snail's stability and prevent it from toppling over as it hops. Juveniles lack the spikes.

Like many other sea snails, it has large eyes on long stalks, a thick siphon, and a curved "operculum," meaning "little lid," attached to a strong foot. This is used by the animal to hop along the surface and as a trap door concealing it into its shell.

The color of the shell is highly variable, with the base being white or cream and often presenting, tan, brown, purplish, or bluish-black patches. The interior appears polished and may be pink, orange, or purple.

The Spider Conch is another favorite for crafters and collectors.

It thrives on red algae.

• Size: Up to 11.5 in (29 cm), average 7 in (18 cm)
• Habitat: Mangrove areas, reef flats, and coral-rubble in shallow water from low tide levels to depths of 5 m
• Range: Widespread in Indo-Pacific from Africa to Australia, including India, Persian Gulf, Southeast Asia, north to Southern Japan
• Latin name: Lambis lambis

5. Queen (Emperor) Helmet Snail

The Queen Helmet, also known as the Emperor Helmet, may be one of the larger sea snail species. However, today they are not easy to find due to over-collecting.

Heavy, large, triangular, thick-lipped, and varied, Helmet shells are used in making cameos. The thick shell and variable colors suit them well for this purpose.

Queen Helmet shells may vary from whitish color to light yellowish brown. Their undersides are darker and have a wide opening with markings that resemble teeth. They feed on sea urchins and sand dollars.

• Size: Up to 12-14 in 3-5 cm
• Habitat: Sandy shallow warm water in coral reefs up to 30 feet deep
• Range: Atlantic coast, the Gulf of Mexico, and the Caribbean Sea regions. The specific name madagascarensis literally means "of Madagascar," but this was a misunderstanding of the locality by the original author.
• Latin name: Cassis madagascariensis

6. Cameo Helmet

The Cameo Helmet, also called Bull Mouth, Grinning Mouth, or Red Helmet, are characterized by thick, heavy shells that are used in making cameos. Colors may vary from light pinkish to deeper pink with dark striped markings. The helmet snails are distinguished from the conchs by their flipped-up rims along their openings, and short spires. Usually, their knobs along the whorls are blunt. The undersides have markings that resemble teeth and a wide lid bears faint wide stripes. They feed on sea urchins and other echinoderms at night.

• Size: Up to 7.5 in, 19 cm
• Habitat: Tropical sandy coastlines as deep as 40 ft or 12 m
• Range: Indo-Pacific Southeast Africa coastline to Northern Australia and New Guinea
• Latin name: Cypraecassis rufa

7. Lightning Whelk

The Lightning Whelk is one of the loveliest. This particular species acquired the name Lightning Whelk because the white shells of the juveniles have chestnut brown stripes with a zig-zag pattern reminiscent of lightning bolts. Colors fade on older, larger shells. Texas Lightning Whelks are darker brown than Lightning Whelks from other locations.

The opening is always on the left holding it so that the spire is at the top. This sets them apart from other univalves. Their shells are elongated with triangular knobs and the opening extends along their entire length.

• Size: Up to 10-15 in, 25- 38 cm
• Habitat: Sandy bottoms in shallow water
• Range: Atlantic coast as far north as Cape Cod, south to Florida, and west to the Gulf of Mexico
• Latin name: Busycon contrarium (previously Sinistrofulgur perversum)

More About the Lightning Whelk

The elegant big whelks that wash up on the U.S. Atlantic and Gulf Coast beaches are yet another favorite of collectors. When alive, they are edible, especially on European menus. All whelks are predators with a rasping tongue-like structure to siphon into mostly clams or scavenged carrion. Near the base of the siphon is a taste/smell receptor that can detect and locate food at a considerable distance.

8. Knobbed Whelk Snail

The Knobbed Whelk is the second largest species of the "Busycon" Whelks. Distinguishing features, of course, are the protruding knobs or spines along the shoulder of its wide whorl, but they can become worn down by sand and surf, as seen in the example above the video. Their shell opening is right-sided and elongated.

As with other whelks, the shell color varies depending on geographic locations: the outer shell ranges from grayish white to tan, while the inner shell ranges from pale yellow to orange.

This animal feeds on clams, oysters, mussels, and other bivalves. To feed, the snail uses its foot to hold prey while the lip of its shell chips and pries at the bivalve. Once a big enough hole has opened, the snail inserts its foot and begins to feed.

Historically, Native Americans used the Knobbed Whelk to make their beaded wampum belts in exchange for trade.

They are edible and have lived on Mother Earth for 30 million years!

• Size: Up to 12 in, 30 cm
• Habitat: Sandy tidal zones, but can be found offshore up to 150 ft, 45 m.
• Range: Massachusetts to Florida, west to the Gulf Coast of Georgia
• Latin name: Busycon carica

9. Common Northern Whelk Snail

The Common Northern Whelk has a stout pale shell that is white, yellowish, or reddish-brown in tone. In life, the outer shell is covered in a bright, yellowish-brown protective cover called periostracum, as with many other marine bivalves and univalves. The spire contains seven to eight whorls. There are wavy folds crossed by numerous prominent spiral lines. The opening is white and broad.

It does not adapt well to life in the intertidal zones. If exposed to air, it may crawl from its shell, risking desiccation.

They are widely eaten, sometimes referred to by their French name bulot.

• Size: Up to 3 in, 8 cm
• Habitat: Offshore, beyond high watermark in continuous submerges zones
• Range: Preferring colder water widely distributed from North America as far south as New Jersey, west to European Northern Atlantic coastlines as far north as Iceland
• Latin name: Buccinum undatum

10. Giant Eastern Murex

Murex shells and their kin include over a thousand species, counting the Drills, which have become serious pests in oyster beds. All of this group are carnivores, feeding mainly on bivalves. Their outer shells are heavy, ridged, and spiny, and very attractive to collectors.

The Giant Eastern Murex, also known as the Giant Atlantic Murex, is uncommon compared to other species of Murex, so to have one in your collection is very lucky. As the name suggests, they are big sea snails—the biggest of the Murexes. They possess several rows of ridges with glorious protruding spines. Their outer shell may be colored whitish, grayish, or pale brown, the aperture is oval with hollow spiny edges.

• Size: Up to 9 in, 23 cm
• Habitat: Most commonly in deeper waters 250 ft, 80 m.
• Range: North Carolina to Cape Canaveral, Florida, west to Texas and the Gulf of Mexico
• Latin name: Hexaplex fulvescens

11. Lace Murex

The Lace Murex is highly ornamental with up to seven whorls and 10 hollow decorative spines. The colors vary from yellowish, light-brown, or brownish-black in mature specimens, to pink or white in young specimens.

The Lace Murex and Apple Murex are very similar, except the Lace Murex has hollow spines along the outer rim of its aperture or opening, lacking in the Apple Murex. Also, the Lace Murex opening is on the smaller side.

• Habitat: Shallow sand and rubble
• Size: Up to 3 1/2 in, 7 cm
• Range: North Carolina, south to Florida, the Caribbean, and the Bahamas; west through the Gulf of Mexico
• Latin name: Chicoreus florifer

12. Apple Murex

The Apple Murex is mostly tan or light brown with darker brown markings and white highlights. The shell is thick and the surface is rough and ridged with wrinkly columns. The aperture is glossy and either white, tan, or peach.

The samples above are immature, and the spires are not as pronounced as with an adult size. The sample above measures to only about an inch and a half.

• Size: Up to 5 in, 13 cm
• Habitat: Shallow bottoms to deeper waters up to 70 ft, 20 m, burying themselves during low tide
• Range: North Carolina to Florida, as far south as Brazil, west through the Gulf of Mexico
• Latin name: Phyllonotus pomum

13. Pink Throat Murex

The Pink Throat Murex has a light tan shell with yellowish brown patches and a number of blunt spines along several ridges. The aperture is large and round and bends backward over the outer shell. The interior is usually pink and glossy, but sometimes it's white depending on its location and especially maturity level, only adults have the deep pink.

• Size: 3-6 in, 7-15 cm
• Habitat: Moderately shallow water
• Range: Western Mexico, as far south as Peru, and parts of the lower Gulf of Mexico
• Latin name: Hexaplex erythrostomus

14. Atlantic Oyster Drill

The Atlantic Oyster Drill, related to the family of Murexes, has sturdy, longitudinal ribbed shells with prominent spires. The color is grayish, brownish over dull white, sometimes yellow or light brown. The outer lip is slightly thick inside.

A vicious enemy to oysters, it has the ability to bore a hole and suck out the oyster; a serious problem in commercial oyster beds, and it has been accidentally introduced well outside its natural range. Is non-edible.

• Size: 1/2 to 1 in, 1.25 to 2.5 cm
• Habitat: Intertidal rock and oyster beds as far as 25 feet
• Range: Nova Scotia to southern Florida
• Latin name: Urosalpinx cinerea

15. Florida Rock Snail

The Florida Rock Snail is in the Murex family and may also be called an Oyster Drill, Red-Mouthed Rock Shell, or the Florida Dog Winkle. It has a solid elongated shell with a tall spire. It's sculptured with longitudinal ribs sometimes with nodules on the shoulder and weaker concentric growth lines.

Colors variable creamy white with brown, tan, or blue-gray bands sometimes creating a checkered almost plaid-like pattern. The innermost interior is deep brown or purple outlined with orange and often grooved on the outer lip.

Rock Oysters are known to feed on other oysters and mussels and may be able to attack those prey in groups, to maximize feeding efficiency. Their feeding behaviors include chipping away at the shell margins of prey using their teeth (called radula) and acid secretions.

• Size: Up to 4 1/2 in, 11 cm
• Habitat: Rock beds, oyster beds
• Range: Widespread on the U.S. Atlantic coast from North Carolina to Florida and Caribbean as far south to Brazil. Also on the European Atlantic coast and the Mediterranean northern tip of Africa.
• Latin name: Stramonita haemastoma floridana

16. Triton's Trumpet (Giant Triton)

The Triton's Trumpet, also called Giant Triton, is a very large species of sea snail; one of the biggest mollusks in the coral reef named (Triton) the son of the Greek god of the sea (Poseidon).

Tan with darker brown markings, Triton's Trumpet is heavily beaded with a pointed spire and large body whorl with spiral shelves. The Interior opening has notched edging and is white.

It's one of the few animals that feed on the Crown of Thorns Starfish, a large and destructive species having killed extensive areas of coral on the Great Barrier Coral Reef of Australia. This Triton has a reputation for tearing apart the starfish to pieces with its file-like radula.

It is a decorative treasure sometimes modified to a trumpet, such as the Japanese "horagai."

It's a protected species in Australia and other countries such as India but is illegally traded and found in shops around the world and on the internet for sale!

• Size: Up to 2 ft, 60 cm (my sample is juvenile, only about 6 in, 15 cm)
• Habitat: Coral reef
• Range: Widespread in the Indo-Pacific from the Red Sea to Japan, New Zealand, Australia, the Mediterranean from East Africa to Hawaii
• Latin name: Charonia tritonis

17. Girdled Triton Snail

The Girdled Triton is sculptured with small spines arranged along deeper cut ribs. The tail is turned to one side. The color varies with white background, light-gray and brownish markings, or rarely greenish.

• Size: Up to 2 3/4 in, 7 cm
• Habitat: Seagrass meadows on soft substrates
• Range: This species is very widespread (but uncommon). On the Atlantic coast from South Carolina to Brazil, across to the Canary Islands. It is also present in European waters, in the Mediterranean Sea, in the Red Sea, and in the Indian Ocean along Tanzania and in the Indo-Western Pacific as far north as southern Japan.
• Latin name: Linatella caudata

18. Banded Tulip Snail

The Banded Tulip is whitish to orange-yellow. The dark distinct spiral lines are less crowded than with their relatives, the True Tulip. They are shaped like a spindle that opens in the middle and forms a pointy spire on the ends. They prey on other mid-size gastropods.

• Size: 3-4 in, 7-10 cm
• Habitat: Sandy or muddy shallow water less than 100 ft, 30 m
• Range: North Carolina, south to Florida, west to the Texas Gulf
• Latin name: Fasciolaria lilium

19. Alphabet Cone Snail

The Alphabet Cone is a medium size and obviously shaped like a cone, as with all the cones from which there are about a dozen species in the Florida corals and rocks. The opening lip is narrow and extends the length of the outer shell. They are creamy-white with rows of reddish brown splotches, some resembling letters of the alphabet. The top of the cone or spire has a small pointy apex.

All cone snail stings are toxic; always use caution when collecting their shells.

• Size: Up to 3 in, 8 cm
• Habitat: Sandbars and grassy flats in shallow water
• Range: North Carolina to Florida
• Latin name: Conus spurius

20. Nutmeg Snail

The Nutmeg Snail is small and resembles the shape of a nutmeg seed with the same roughness and texture. Background of white with various shades of brown arranged in spiral bands and longitudinal stripes. Both ends are pointy. It's a vegetable feeder.

• Size: Up to 1 3/4 in, 3 cm
• Habitat: Grassy bottoms or kelp beds
• Range: North Carolina around Florida to its west coast, mostly around Cape Sable at Florida's southern tip
• Latin name: Cancellaria reticulate

21. Cuming's Cerith Snail

The Cuming's Cerith, Pseudovertagus aluco, is an Indo-Pacific species that is very similar to the Dark Cerith or Florida Cerith (shown below), so I have decided to use it for comparison.

• Note about Ceriths: You may find them scurrying around in shallow ocean lagoons, but look more closely. There may be a hermit crab occupying it, so when you collect the long slender Ceriths, make sure they are empty of living creatures.
• About 30 species of Ceriths are found on North American coasts in warm or temperate waters. They feed on mostly waste matter or algae and people like to put them in aquariums as cleaners.

22. Florida (Dark) Cerith

Above is the Florida Dark Cerith, Cerithium atratum.

Comparing the Cerith Species

After observing the above two Cerith species, I'm sure you can see their similarities and differences. One main difference is in their size, which you can't tell by the photos. The Florida Cerith, is much smaller, about 1 1/2 inches while the Indo-Pacific Cuming's species is 3 1/2 inches. Both are at full adult size. The Florida species is lighter tan with stripped bands while the Cuming's has a more speckled pattern. Also, the Cumings has distinct knobs while the Dark Cerith is beady. The point is when you're identifying species, you learn to be a much more careful observer. One can be easily mistaken for another.

• Habitat: Both species like sand-bars at the high tide level, sandy shallows, or coral rubble
• Dark Cerith Range: The Dark Cerith is found mainly from North Carolina to Florida and west to Texas
• Cuming's Cerith Range: The Indo-Pacific region from the eastern African coast to the Philippines and northern Australia

23. Common (Atlantic) Auger Snail

The Common or Atlantic Auger, also called Eastern Auger, can be colored from gray to tannish-white. The Augers are relatives of the Cones. This is the most abundant of the four species of auger snails living on the sandy shores of southwest Florida. They have a slender triangular shape, with a small aperture and a very long spire. They feed on small crustaceans, clams, and worms.

You wouldn't want to pick up a live auger because they have venomous, stinger-like teeth to subdue their prey, and the flesh may also be poisonous depending on the species.

During mating season, they may be observed in populated swarms.

• Size: Up to 2 1/2 in, 6 cm
• Habitat: Muddy sand or sand flats in intertidal shallows up to 25 feet
• Range: Florida to Texas
• Latin name: Terebra dislocata

24. Adam's Miniature Cerith

The Adam's Miniature Cerith has a slender conical shell with flat whorls sculptured with three strong, spiral cords distributed evenly on whorls. It is typically colored orange to dark brown.

• Size: 1/2 in, 13 mm
• Habitat: Shallow waters
• Range: Massachusetts to Florida, south to the West Indies
• Latin name: Seila adamsi

25. Boring Turret Snail

The towering Boring Turret Snail is not as commonly found because it remains offshore farther than most. Colors vary from whitish tan with pinkish and orange-brown irregular mottling. Adults may have up to 15 whorls that bulge with fine concentric lines.

The Turritelline gastropods are moderately diverse and abundant.

• Size: Up to 4 in, 10 cm
• Habitat: Offshore, moderately shallow waters
• Range: North Carolina, Florida, much of the Gulf Coast, south to Cuba and the Bahamas
• Latin name: Turritella acropora

26. Rough Turban

The Rough Turban is usually green with brown patches and a pearly white aperture. The texture is beaded, and the top spire is acute and pointed

• Size: Up to 3 in, 8 cm
• Range: Indian Ocean east to the northern shores of Australia
• Latin name: Turbo setosus

General Info About Turbo Snails

Turbo Snails are found in tropical regions around the world. They were in existence as early as the Upper Cretaceous period approximately 100 million years ago.

• Empty turbo snail shells are a favorite choice of hermit crabs and favorites among collectors who love to polish them beautifully and put them on the market for sale.
• All turbo shells have round to semi-circular apertures with inflated, thick shells topped with swirling spires, giving them the appearance resembling a turban (a wrap-around headdress).
• Most young snails feed on algae, while adults feed on seaweed.
• The majority of species live in shallow warm coastal waters and reefs up to 90 ft (30 m) deep.

27. Wavy Turban

The Wavy Turban varies from olive, green, brown, or grayish with varying patterns. The aperture is white.

• Size: Up to 3 1/2 in, 9 cm
• Range: Pacific Ocean from Southern California farther south to the western Mexican coastline and Peru, further west to Galapagos Islands
• Latin name: Turbo fluctuosus

28. Gold Mouth Turban

The Gold Mouth Turban is a rough textured shell. The color is a patterned brownish or white, marbled with chestnut to red flecks. Of course, the best way to be sure of its identity is its richly golden, shiny aperture.

• Size: Up to 3 in, 8 cm
• Range: Indian Ocean off Madagascar Basin. Also western Pacific Philippines and south to northern and western Australia
• Latin name: Turbo chrysostomus