Bothragonus

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Bothragonus
Bothragonus swanii

Bothragonus swanii

Systematics
Order : Perch-like (Perciformes)
Subordination : Cottoidei
Partial order : Bull relatives (Cottales)
Family : Panzerroppen (Agonidae)
Subfamily : Bothragoninae
Genre : Bothragonus
Scientific name
Bothragonus
Gill in Jordan & Gilbert , 1883

Bothragonus is a genus of marine fish from the family of armored lobsters (Agonidae). Of the two species in the genus, Bothragonus swanii occurs on the North American Pacific coast from Kodiak Island to California , while Bothragonus occidentalis only occurs on the coasts of the Japanese island of Hokkaidō , the Kuril island of Chabomai and the Peter the Great Bay in the Russian Far East is known.

features

Panzerropen of the genus Bothragonus are seven to nine centimeters long. They don't have barbels . The tubular outer nostrils do not reach the tip of the upper jaw. Both nasal bones are in contact with each other and with the tear bone. The nasal bones are about as long as the upper jaw. The rostral bone, parietal bone and ethmoid bone are without spines. The Urohyale, a tendon ossification in the skull, is plate-shaped. A basihyale, an element between the hyoid bones in many fish, and abdominal ribs are missing. In contrast, there are three basibranchials, bones at the base of the gill arch. With Bothragonus, the lower jaw is completely enclosed by the upper jaw when the mouth is closed. The palatine bone and preventer are dentate. The skull is indented between the orbit . The number of Branchiostegal rays is six, those of the vertebrae 32 to 38. Bothragonus has two postcleithra (bones in the shoulder girdle).

The body is covered with bone plates. Six to eight are located in front of the dorsal fin, 31 to 36 along the sideline . The back profile shows a large pit just behind the head. Bothragonus has three basal bones at the base of the pelvic fins and a spine behind them. In the tail fin skeleton there are two epurals (elongated, free-standing bones).

species

literature

  • Joseph S. Nelson : Fishes of the World , John Wiley & Sons, 2006, ISBN 0-471-25031-7 .
  • Tsutomu Kanayama: Taxonomy and Phylogeny of the Family Agonidae (Pisces: Scorpaeniformes). Memoirs of the Faculty of Fisheries, Hokkaido University, vol. 38, no. 1-2.

Web links