Phyllorhinichthys is a genus of deep-sea anglerfish in the dreamer family, Oneirodidae

Oneirodidae

The dreamers are a family, Oneirodidae, of deep-sea anglerfishes in the order Lophiiformes. They are the largest and most diverse group of deep-sea anglerfish, and also the least well-known with several genera represented by only one, two, or three female specimens. They are found in deep,...

, with two species. Like other oneirodids, they are small, bathypelagic fish with bioluminescent lures. Phyllorhinichthys is unique amongst the deep-sea anglerfish in having a pair of fleshy, leaf-like structures on its snout.

Distribution and habitat

P. micractis has been collected from all three major ocean

Ocean

An ocean is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas.More than half of this area is over 3,000...

s from a maximum depth of 3500 meters, ranging from near Newfoundland and Bermuda

Bermuda

Bermuda is a British overseas territory in the North Atlantic Ocean. Located off the east coast of the United States, its nearest landmass is Cape Hatteras, North Carolina, about to the west-northwest. It is about south of Halifax, Nova Scotia, Canada, and northeast of Miami, Florida...

 in the Atlantic Ocean

Atlantic Ocean

The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...

, to the Horn of Africa

Horn of Africa

The Horn of Africa is a peninsula in East Africa that juts hundreds of kilometers into the Arabian Sea and lies along the southern side of the Gulf of Aden. It is the easternmost projection of the African continent...

 in 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...

, to Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

 and the Line Islands

Line Islands

The Line Islands, Teraina Islands or Equatorial Islands, is a chain of eleven atolls and low coral islands in the central Pacific Ocean, south of the Hawaiian Islands, that stretches for 2,350 km in a northwest-southeast direction, making it one of the longest islands chains of the world...

 in the Pacific Ocean

Pacific Ocean

The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...

. P. balushkini has only been collected in the Atlantic Ocean, ranging from the north to the tropics from a maximum depth of 3200 meters.

Description

Adult female Phyllorhinichthys have a short, somewhat globulose body, entirely dark brown to black in color. In smaller specimens (8.8-18.3 mm), there is a distinct band of melanophores on the caudal peduncle. The mouth is small and oblique, with slender, depressible teeth; the teeth are slightly larger but fewer in the lower jaw. The illicium ("fishing rod") is short; the escal bulb ("lure") is internally pigmented on the upper half and unpigmented on the lower, and bears internally pigmented appendages with silvery tips. The most distinctive feature of the genus are a pair of translucent leaf-like flaps on the snout, forward of the eyes and flanking the esca. Each flap has a central opaque nerve fiber running from the base to the tip. In some specimens, there is another, smaller pair of similar flaps placed above the main pair. Males and larvae have yet to be encountered.

Species

The two species of Phyllorhinichthys are differentiated by the length of the illicium and details of the esca.

• Phyllorhinichthys balushkini Pietsch, 2004 The illicium is longer than that of P. micractis. The esca bears a single forward appendage containing a pair of internal light-guiding tubes that diverge from each other at the tip. The rear escal appendage is extremely long, measuring over half the length of the fish, covered with dark skin and ending in a pair of translucent bulbs. The snout flaps are relatively small. The largest known female measured 14.5 cm long.

• Phyllorhinichthys micractis Pietsch, 1969 The illicium is shorter than that of P. balushkini. The esca has two forward appendages at the tip and the rear appendage is much shorter and stouter than that of P. balushkini. The available specimens vary in the number and presence of additional appendages and filaments. The size of the snout flaps are also highly variable. The largest known female measured 12 cm long.