Clearnose Skate

Quick Take

• Clearnose skates and stingrays look almost identical, yet one key physical difference separates them in ways most people never notice. Skates vs. rays origins →
• This fish's mating ritual involves biting, a multi-hour embrace, and a process so elaborate it defies what most people picture when they think of fish reproduction. See the mating behavior →
• Clearnose skate eggs have a name so strange it sounds made up, and the story behind how they're laid is even stranger. Discover mermaid's purses →
• Despite being edible, clearnose skate is almost never commercially fished, and the reason behind this is not what you would expect. Why it's rarely fished →

The clearnose skate is a small, flat-bodied fish inhabiting the western Atlantic Ocean. Alternate names for this species include brier skate and summer skate. Though skates appear similar to rays, there are notable differences. For example, skates have thorns on their backs instead of stingers on their tails. They also have pelvic fins with two lobes instead of one. The clearnose skate prefers benthic habitats, roaming the sea floors of coasts and inland bays.

4 Clearnose Skate Facts

• Thorns on its back: Unlike rays, which have stingers on their tails, skates have thorns on their backs. These thorns or spines are not venomous, though they have the potential to cause injury if handled.
• Translucent patches on its snout: This species gets its name from the two translucent patches on its rostrum (snout).
• Lays eggs in “mermaid’s purses”: Females lay pairs of eggs in egg cases with the dreamy name “mermaid’s purses.” These cases are rectangular with curved horns on either end.
• One of the smallest skates: This species is on the small side, with a maximum length of 33 inches. This is only slightly larger than the smallest species, the starry skate (Raja stellata), which only grows 30 inches long.

Classification and Scientific Name

The formerly accepted scientific name for the clearnose skate was Raja eglanteria. However, recent genetic analysis has reassigned it from the genus Raja to the formerly monotypic genus Rostroraja, updating this fish’s name to Rostroraja eglanteria. This genus contains a number of species previously belonging to Raja. Other former taxonomic synonyms for the clearnose skate (rarely used) were Raja diaphanes, Raja desmarestia, and Raja chantenay.

Scientists classify this species as a cartilaginous fish in the class Chondrichthyes. Fish in this taxon have skeletons made primarily of cartilage instead of bone. The skate’s subclass is Elasmobranchii, which encompasses sharks, rays, skates, and sawfish. Scientists further group it into the order Rajiformes with over 500 ray and skate species, as well as the family Rajidae with over 200 skate species. Its genus, Rostroraja, comprises eight species, including the ocellate skate (Rostroraja ackleyi), the bottlenose skate (Rostroraja alba), and the equatorial ray (Rostroraja equatorialis). At one time, this genus contained only Rostroraja alba.

Appearance

The clearnose skate is a flat-bodied fish shaped like a rhombus. It derives its name from the two translucent patches on either side of its pointed rostrum. Its upper jaw contains 46 to 54 teeth, while the lower jaw has 48, arranged differently in males and females. Males have sharper teeth. This species’ dorsal region, including its discs or “wings,” is brown or grey with irregular spots and bars as well as occasional lighter patches. The ventral region is white. The front edges of the discs may be either almost straight or somewhat concave.

A single line of thorns extends along the dorsal midridge. Additionally, smaller prickles on the back have given rise to the nickname “brier skate.” Like other skates, this species does not have a stinger on its tail, though it does have a pectoral fin on either side. Males possess a pair of “claspers” to help them while mating.

Smaller in size than many other skates and rays, this fish typically measures 19 to 24 inches in length upon reaching maturity. However, the largest individuals may grow up to 33 inches long. The tail accounts for about half of each individual’s total length. Disc width is 13 to 21 inches. The average weight for this species is 30 to 40 pounds.

Distribution, Population, and Habitat

The clearnose skate is a saltwater fish inhabiting the western Atlantic Ocean along the eastern and southern coasts of the United States and the northern coast of Mexico. Its range extends into the northern and eastern Gulf of Mexico. US states within its range include Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Delaware, Maryland, Virginia, North Carolina, South Carolina, Georgia, Florida, Alabama, Mississippi, Louisiana, and Texas. Most populations exist north of South Carolina.

This demersal fish lives near the sandy bottoms of saltwater estuaries and inshore bays at depths of up to 1,083 feet, though it usually descends no deeper than 365 feet. Its preferred water temperature is 50°–70°F. In warmer months, it migrates northward, returning to southern waters in fall and winter. Breeding occurs inshore.

As of 2019, the IUCN lists this species as Least Concern due to increasing populations. NOAA Fisheries manages the clearnose skate as part of the Northeast Skate Complex fishery, but it is not classified as a prohibited species.

Evolution and History

As with most cartilaginous fish, the ancestors of clearnose skates have left little fossilized evidence for scientists. Cartilage is softer than bone and therefore does not readily fossilize. Teeth and scales are the main evolutionary indicators. The oldest ray and skate fossils come from the Lower Jurassic period, approximately 150 million years ago. However, some speculate that these fish diverged from a bottom-dwelling sharklike ancestor, possibly a hybodont shark, as far back as 200 million years ago.

The main elasmobranch taxa in use today developed between the Upper Cretaceous (100 million years ago) and the Paleocene (50 million years ago). The greater diversity of benthic habitats may have inspired increased speciation among rays and skates as opposed to sharks, which are primarily pelagic. However, some shark species remain phylogenetically closer to rays and skates than to other sharks.

Scientists consider the family Rajidae to be monophyletic (having a single common ancestor). Skates retain the limited reproductive potential of other elasmobranchs like sharks, rays, and sawfish. This has historically limited their ability to recover from threats such as habitat destruction and overfishing.

Predators and Prey

Clearnose skates are carnivores that feed on a variety of small marine organisms. Though they have a few natural predators, humans do not typically catch or eat them. This is because of their small size and limited edible flesh.

What Do Clearnose Skates Eat?

Clearnose skates primarily hunt crustaceans, like shrimp and fiddler crabs, and mollusks. Their teeth are blunt and packed close together, allowing them to crack or crush the shells of their prey. Worms and small fish are also potential targets. As nocturnal fish, clearnose skates hunt primarily at night by gliding along the sea floor. They may also choose to camouflage themselves by burrowing into the sandy substrate and waiting for prey to swim by.

What Eats Clearnose Skates?

Various species of sharks and large carnivorous fish hunt this species. They use their flat bodies and deceptive coloration to hide on the sea floor.

Reproduction and Lifespan

Clearnose skates are solitary except when mating. They are oviparous, meaning they lay eggs that later hatch to produce young. Males mature between two and four years old, while females mature somewhat later, between four and six years old. They breed only once a year along the western coast of Florida between December and mid-May. Mating occurs when the water temperature is between 60.8° – 71.6°F (16° – 22°C).

Males and females meet inshore and mate side by side in an upright position. The male approaches from behind and latches onto the caudal margin of one of the female’s pectoral fins with his sharp teeth. He holds on using his teeth, jaws, and the spines on his dorsum, pectoral fins, and eye region. The male and female may remain in this embrace for one to four hours without copulating.

To initiate copulation, the male bends his tail under the female’s tail and pelvic fin. A clasper gland lubricates one of his claspers, which the male inserts slowly into the female’s cloaca at a right angle. If he attaches himself to the female’s right pectoral fin, he uses his right clasper and vice versa. The process of insertion can take over an hour. The clasper expands to anchor itself. The male then releases sperm into the female’s oviductal glands.

The female lays fertilized eggs in egg cases called “mermaid’s purses.” These cases are rectangular with curved horns. She lays the eggs in pairs, up to 30 pairs at a time. A sticky substance on the egg cases anchors them to the sandy substrate, providing security and protection. The eggs hatch after 62–96 days; warmer temperatures shorten the incubation period. The pups are fully independent after hatching and live up to five years.

Fishing and Cooking

The only edible part of the clearnose skate is its wings, which feature lean, stringy strips of meat on both sides of a thin layer of cartilage. Because the meat is so sparse and difficult to remove, it is not an economically feasible commercial catch for most fisheries. However, individuals sometimes end up as bycatch on longlines or in gillnets.

Much like commercial fisheries, recreational or sport anglers rarely attempt to catch this species. Because it will go after almost any bait, it sometimes gets caught on hooks, making it a nuisance to anglers. It can also be difficult to remove from the hook due to its spines and teeth.

Clearnose skate has a fairly mild flavor similar to that of scallops. The flesh is soft and lean. Those who enjoy the taste of clearnose skate wings can try making them with tomatoes and capers or with brown butter. Those who are unsure about skate as a dish can check out this Washington Post article for more information and a recipe.

Exact nutritional information varies slightly according to the species of skate, but an average 100-gram serving contains approximately 95 calories, 21 grams of protein, and one gram of fat.