Kuhl's maskray

Kuhl's maskray was discovered by Heinrich Kuhl in Java, Indonesia. The population size of this species is greatly debatable due to the five different species of rays in Indonesia. Also, two different subgroups are known, the Java and Bali forms.[6] The distinct difference between the two strains is their size, with the Bali being much larger than the Java.[7] On the familial level, the family Dasyatidae is made up of 9 genera and 70 species. The species in Neotrygon are called maskrays, because of the color pattern around their eyes.

The full body of a blue-spotted stingray, showing the black-and-white-striped tail

Kuhl's maskrays have a flat, disc-like, rhomboid body up to 47 cm (19 in) in diameter and 70 cm (28 in) in total length.[7][8] Their coloring is a dark green with blue spots with a light white underbelly, also known as countershading. Their snouts are very short and broadly angular along with an angular disc.[7] The rays' bright coloration serves as a warning for their venomous spines. The rays have a very long tail accommodating two venomous spines on its base. Their tails are about twice as long as their bodies, and the barbs or spines are two different sizes, one being very large and the other medium in size. Kuhl's maskrays have bright yellow eyes that are positioned to allow them a wide angle of view. Since their gills are located ventrally, the spiracles allow water to reach the gills while resting or feeding on the benthos. The spiracles are located directly behind the eyes. The mouth is located on the ventral side of the body, which promotes the unique foraging technique of stingrays.[9] Rays are normally solitary individuals, but can occur in groups. One unique characteristic of Kuhl's maskrays is that they bury themselves in the sand only to hide from predators, unlike most stingrays, which bury themselves regularly to hunt.[9]

Shrimp, one of the blue-spotted stingray's food sources

Blue-spotted maskray range map

The blue-spotted stingray is commonly found in waters of depths above 90 m (295 ft), being commonly found in sand and mudflats, but is also encountered near rocky coral reefs and sea grass beds. This stingray is found in a tropical climate at 29°N to 31°S, and 20°E to 171°W.[7] At high tide, the blue-spotted stingray moves into the shallow lagoons and reef flats.[6] It is found in northern Australia, Kenya, Madagascar, Mauritius, Somalia, the east coast of South Africa, and India, and in almost the entire continental waters of Asia, including the Sea of Japan, Yellow Sea, East China Sea, Philippine Sea, Sulu Sea, Java Sea, Banda Sea, Celebes Sea, Andaman Sea, the Bay of Bengal, and the Arabian Sea.[12]

The body of a Kuhl's maskray is more angular, which distinguishes it from the blue-spotted ribbontail ray.

Queensland, Australia, has many areas for high protection of Kuhl's maskrays, three being the Shoalwater, Corio Bay's Area Ramsar Site, and the Great Barrier Reef Marine Park. A major threat to this stingray is the destruction of coral reefs mainly in the north-western Pacific. The rays dwell in these reefs and the destruction and pollution from fertilizers and pesticides hurt them.[9] The ray is commonly caught in the Java Sea by fishermen trawling and by Danish seine boats in large quantities. The blue-spotted stingray is the second-most significant species of the shark, ray, and skate family to be fished, contributing to about 700 kg (1,500 lb) per boat in 2006–2007.[13]

Larger elasmobranchs, such as hammerhead sharks, prey on Kuhl's maskrays. The rays' coloration is a warning for the highly venomous barbs, thus few animals attempt to overpower them.[10][14] The hammerhead shark uses its head to pin down this stingray, while it is in shock and much weaker.[15]

Due to the unique characteristics of this ray, it is commonly found in pet trade, but many people ignore the fact that the fully mature size of the ray exceeds the capacity of many household aquaria.[9] Kuhl's maskray is generally fished for its meat, being either smoked and salted or dried for local markets, but inexpensive due to its small size.[7][13] It is caught in mass in bottom trawl, trammel, and fish traps. Kuhl's maskray is very venomous and it has a barb about 12 in (300 mm) long. The venom contains serotonin, 5' nucleotidase, and phosphodiesterase.[16]

The skin of the blue-spotted stingray is often used for drums, such as on the Arab and Turkish darbuka goblet drum and riq tambourine.

Many parasites can inhabit the blue-spotted stingray:[17]

External video
Blue spotted stingray swimming YouTube
Hand feeding a blue spotted stingrayYouTube
How Whales Eat Sharks National Geographic

Two short peptides identified from the hydrolyzed proteins of this species showed protective effects against the oxidation of lipids, DNA and proteins. The potential application of the peptides as functional food ingredients or nutraceuticals has been proposed.[18]

• Randall, John E. (2005). Reef and Shore Fishes of the South Pacific: New Caledonia to Tahiti and the Pitcairn Islands. University of Hawaii Press. ISBN 978-0-8248-2698-7.

Wikimedia Commons has media related to Neotrygon kuhlii.

• Bluespotted Ray Photo Gallery (Red Sea)
• Photos of Kuhl's maskray on Sealife Collection

&