Gollum (genus)

Gollum
	Gollum attenuatus , the type species of the genus .
Systematics
Subclass :	Plate gill (Elasmobranchii)
without rank:	Sharks (selachii)
Superordinate :	Galeomorphii
Order :	Ground Sharks (Carcharhiniformes)
Family :	Pseudotriakidae
Genre :	Gollum
Scientific name
	Gollum
	Compagno , 1973

Gollum is a genus of small sharks from the order of the ground sharks (Carcharhiniformes). The genus consists of two types. Gollum attenuatus occurs at depths of 130 to 730 meters around New Zealand and Gollum suluensis is so far only known from the Sulu Sea . The genus was named after Gollum , a character from JRR Tolkien's fantasy novel The Lord of the Rings .

features

Gollum species are small deep-sea sharks with a firm, slender body and reach overall lengths of 60 to 110 cm. The head length makes up a quarter of the head body length (precaudal length). The mouth has a width of 70 to 80% of the head width. The spray holes are very small. A nictitating membrane is present. The base of the first dorsal fin is shorter than that of the second. Both dorsal fins are about the same height. The second dorsal fin is sickle-shaped. Both dorsal fins are far apart and the distance between the two is longer than the total length of the second dorsal fin. Gollum species have 151 to 168 vertebrae and 94 to 99 rows of teeth in the upper jaw. The heterodontics of the teeth are poorly developed. The sides of the body are densely covered with small, overlapping placoid scales. There are 14 to 17 scales on an area of one mm². The tail stalk is 8 to 10% of the total length of the fish. On the top of the caudal fin is a series of larger denticles.

species

Slender smooth shark ( Gollum attenuatus (Garrick, 1954) ), type species
Gollum suluensis Last & Gaudiano, 2011

literature

Compagno, LJV Ctenacis and Gollum , two new genera of sharks (Selachii; Carcharhinidae) . Proceedings of the California Academy of Sciences. 39 (14): 257-272.
Leonard JV Compagno: Sharks of the World. An Annotated and Illustrated Catalog of Shark Species Known to Date. Part 2 - Carcharhiniformes. FAO Species Catalog vol. 4. FAO, Rome 1984. ISBN 92-5-101383-7 . download Gollum on page 375.

supporting documents

↑ ^a ^b Ebert, DA, KV Akhilesh and S. Weigmann (2018): Planonasus indicus sp. n., a new species of pygmy false catshark (Chondrichthyes: Carcharhiniformes: Pseudotriakidae), with a revised diagnosis of the genus and key to the family. Marine Biodiversity, August 2018, DOI: 10.1007 / s12526-018-0915-4

[Ebert-1] Ebert, DA, KV Akhilesh and S. Weigmann (2018): Planonasus indicus sp. n., a new species of pygmy false catshark (Chondrichthyes: Carcharhiniformes: Pseudotriakidae), with a revised diagnosis of the genus and key to the family. Marine Biodiversity, August 2018, DOI: 10.1007 / s12526-018-0915-4