Rajiformes (Skates · Order Overview)

Details

Rajiformes—in modern usage typically referring to the skates within the batoids—differs from stingrays by being oviparous and lacking venomous tail spines. Skates often bear dermal thorns on the back and tail and lay the iconic horned egg capsules known as “mermaid’s purses.”

Ecology & Biology

• Feeding: benthic predators of small fishes, crustaceans, molluscs and polychaetes; mostly ambush/slow cruisers.

• Reproduction: oviparous with horned egg cases that attach to vegetation/substrates; contrasts with the predominantly viviparous stingrays and mantas.

• Life history: slow‑growing, late‑maturing, low fecundity, making them vulnerable to fishing pressure.

Identification

• Disc: pectoral fins fused to the head forming a rhomboid/rounded disc; ventral mouth with nasal lobes.

• Tail: slender with typically one or two small dorsal fins near the tip; no large venomous spines; dorsum/tail often armed with thorns.

• Electric organs: absent (contrast with torpedo rays, Torpediniformes).

Size & Longevity

• Size: disc widths from 30–60 cm in small species to >2 m in giants (e.g., big skates).

• Life: commonly 10–30+ years, longer in large, high‑latitude species.

Range & Habitat

Widespread on temperate to polar continental shelves/slopes over sandy/muddy bottoms; also in subtropical/tropical deep water; predominantly demersal.

Fisheries & Management

• Threats: bottom trawl and gillnet bycatch/targeted fisheries, habitat disturbance and pollution.

• Measures: size (disc‑width) limits, seasonal/spatial closures, essential‑habitat protections and gear modifications.

IUCN: this is an order‑level overview; statuses vary widely among species/populations (LC–EN). Marked here as Not Evaluated (NE) for the overview entry.