Sepia thurstoni is a species of cuttlefish

Cuttlefish

Cuttlefish are marine animals of the order Sepiida. They belong to the class Cephalopoda . Despite their name, cuttlefish are not fish but molluscs....

 native to the Indian Ocean

Indian Ocean

The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...

, specifically the waters off Chennai

Chennai

Chennai , formerly known as Madras or Madarasapatinam , is the capital city of the Indian state of Tamil Nadu, located on the Coromandel Coast off the Bay of Bengal. Chennai is the fourth most populous metropolitan area and the sixth most populous city in India...

 in India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

 and off Negombo

Negombo

Negombo is a town of about 121,933, approximately 37 km north of Colombo, in Sri Lanka. It is located at the mouth of the Negombo Lagoon, about 7 km from the Bandaranaike International Airport...

 and Hambantota

Hambantota

Hambantota is a coastal city in the south of Sri Lanka. It is the capital of the Hambantota District...

 in Sri Lanka

Sri Lanka

Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...

. It lives at depths of 20 to 40 m.

S. thurstoni grows to a mantle

Mantle (mollusc)

The mantle is a significant part of the anatomy of molluscs: it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself.In many, but by no means all, species of molluscs, the epidermis of the mantle secretes...

 length of 110 mm.

The type specimen was collected off Ramesvaram Island in the Bay of Bengal

Bay of Bengal

The Bay of Bengal , the largest bay in the world, forms the northeastern part of the Indian Ocean. It resembles a triangle in shape, and is bordered mostly by the Eastern Coast of India, southern coast of Bangladesh and Sri Lanka to the west and Burma and the Andaman and Nicobar Islands to the...

 (09°18′N 79°19′E) and is deposited at The Natural History Museum in London

London

London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

. It is named after Edgar Thurston

Edgar Thurston

Edgar Thurston CIE was a British museologist and ethnographer working in colonial Southern India. In 1885 he was appointed to the Madras Government Museum, where he held the role of Superintendent...

.