Tarsistes philippii is a taxonomically dubious species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of guitarfish

Guitarfish

The guitarfish are a family, Rhinobatidae, of rays. The guitarfish are known for an elongated body with a flattened head and trunk and small ray like wings. The combined range of the various species is tropical, subtropical and temperate waters worldwide. They often travel in large...

, family Rhinobatidae. It is known only from a dried head from the Juan Fernández Islands

Juan Fernández Islands

The Juan Fernández Islands are a sparsely inhabited island group reliant on tourism and fishing in the South Pacific Ocean, situated about off the coast of Chile, and is composed of three main volcanic islands; Robinson Crusoe Island, Alejandro Selkirk Island and Santa Clara Island, the first...

 off Chile

Chile

Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

. The head had a long, thin, flat snout

Snout

The snout, or muzzle, is the protruding portion of an animal's face, consisting of its nose, mouth, and jaw.-Terminology:The term "muzzle", used as a noun, can be ambiguous...

, rounded at the tip like that of the goblin shark

Goblin shark

The goblin shark, Mitsukurina owstoni, is a deep-sea shark, the sole living species in the family Mitsukurinidae. The most distinctive characteristic of the goblin shark is the unusual shape of its head. It has a long, trowel-shaped, beak-like rostrum or snout, much longer than other sharks' snouts...

, and the underside covered with small stellate prickles except for the base. The head was covered with larger spinules, with six still larger ones forming a curve around the eye.

The original specimen was assigned to the genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 Rhynchobatis without a species name by Philippi in 1858; David Starr Jordan

David Starr Jordan

David Starr Jordan, Ph.D., LL.D. was a leading eugenicist, ichthyologist, educator and peace activist. He was president of Indiana University and Stanford University.-Early life and education:...

 considered that genus name preoccupied (by Rhynchobatus

Rhynchobatus

Rhynchobatus is a group of rays commonly known as wedgefishes, and the sole genus in the family Rhynchobatidae. They are found in the tropical and subtropical Indo-Pacific with a single species in the eastern Atlantic...

) and coined the new scientific name Tarsistes philippii for it in 1919. However, the holotype

Holotype

A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...

has never been studied or described since, and so the status of this species is uncertain.