Striate Anglerfish, Antennarius striatus (Shaw, 1794)

Introduction

The colouration of the Striate Anglerfish is extremely variable. Some are heavily striped, while others have broken stripes or spots, or lack stripes entirely. The species uses deception and camouflage to catch its prey.

Identification

Anglerfishes include some of the best camouflaged of all fishes. They have extraordinary adaptations including a lure for attracting their prey, a large mouth and "hidden gill openings". Striate Anglerfishes are extremely variable in form and colour, and even fish from the same area can look quite different. Colours range from red, orange and yellow, through to green, brown or black. Some are heavily striped, while other Striate Anglerfish have broken stripes or spots, or lack stripes entirely.

The derivation of the scientific name is as follows;
antenna - (Latin) a sensory appendage on the head. Refers to the fish's lure.
arius - (Latin) pertaining to
stria - (Latin) line. Refers to the striped colour pattern of this species.

The derivation of the family, Antennariidae, name is as follows;
antenna - (Latin) a sensory appendage on the head.
idae - a suffix indicating this a family name. All animal family names end in -idae.

Habitat

Anglerfishes occur in many different habitats including sponge gardens, silty substrates, rocky and coral reefs. They are found from the shallow littoral zone down to the abyssal depths of the oceans.

The Striate Anglerfish is known from estuarine water less than 1 m in depth to marine waters more than 200 m deep.

Distribution

Antennariids occur in coastal waters around the world. The Striate Anglerfish occurs in most marine tropical and temperate waters. In Australia, it occurs around the north of the country, from the south-western Western Australia, across the north of the country, and south on the east coast to southern New South Wales.

The map below shows the Australian distribution of the species based on public sightings and specimens in Australian Museums. Source: Atlas of Living Australia.

Feeding and diet

Anglerfishes are superbly adapted predatory fishes. The Striate Anglerfish uses deception and camouflage to catch its prey. When a potential prey animal approaches, the Striate Anglerfish stays motionless with the exception of the lure. If the prey moves in to investigate the moving lure, the anglerfish rapidly opens its large mouth and sucks in its prey. This is one of the fastest known feeding mechanism of any vertebrate animal. The whole process may happen so fast, it is impossible to see without the aid of high speed video. The large mouths and extendable stomachs of anglerfishes means they can eat very large prey.

Other behaviours and adaptations

Gill Openings

The small, tubular gill openings of the Striate Anglerfish are located behind and below the arm-like pectoral fins. These gill openings contract and expand rhythmically, pumping water in through the mouth and out of the gill openings. This behaviour allows the fish to appear motionless to any prey animal attracted by the movement of the lure. In some species, this pumping action can be used to "jet-propel" the anglerfish through the water.

Camouflage

Anglerfishes often combine camouflage with cryptic (hiding/keeping still) behaviour. This not only prevents potential prey from noticing the anglerfish, but also makes the fish less likely to be seen by predators. Most anglerfishes have warts, lumps, bumps or whisker-like filaments on the body, further increasing their camouflage. Others are brightly coloured, mimicking the sponges they live among. The Sargassum Anglerfish, Histrio histrio, lives in seaweed (often Sargassum) rafts drifting in the ocean. The colouration and appendages of this species closely resembles the drifting seaweed. Juvenile Sargassum Anglerfish are sometimes found with their algal raft, floating close to the beaches of Sydney.

Lure

Anglerfishes attract their prey with a "fishing lure". The lure comprises a stalk - the illicium , Latin for "lure" or "inducement" and a bait - the esca. The "design" of the lure varies among genera. In most species, the esca looks like potential prey, such as a worm, crustacean, or even a fish. The anglerfish moves the lure, mimicking the animal it is copying. The esca of the Striate Anglerfish has between two and seven worm-like appendages. When the lure is not being used it is held back against the head. A fish that is trying to attract prey, swings the lure forward in front of the mouth.

Breeding behaviours

frogfishorangspawn15jun15 from Susan Gardner on Vimeo.

References

1. Bertelsen, E. in Paxton, J.R. & W.N. Eschmeyer (Eds). 1994. Encyclopedia of Fishes. Sydney: New South Wales University Press; San Diego: Academic Press [1995]. Pp. 240.
2. Brown, R.W. 1956. Composition of Scientific Words. R. W. Brown. Pp. 882.
3. Grobecker, D.B. & T.W. Pietsch. 1979. High-Speed Cinematographic Evidence of Ultrafast Feeding in Antennariid Anglerfishes. Science. 205:1161-1162.
4. Hoese, D.F., Bray, D.J., Paxton, J.R. & G.R. Allen. 2006. Fishes. In Beesley, P.L. & A. Wells. (eds) Zoological Catalogue of Australia. Volume 35. ABRS & CSIRO Publishing: Australia. parts 1-3, pages 1-2178.
5. Kuiter, R.H. 1993. Coastal Fishes of South-Eastern Australia. Crawford House Press. Pp. 437.
6. Kuiter, R.H. 1996. Guide to Sea Fishes of Australia. New Holland. Pp. 433.
7. Pietsch, T.W. in Gomon, M.F., J.C.M. Glover & R.H. Kuiter (Eds). 1994. The Fishes of Australia's South Coast. State Print, Adelaide. Pp. 992.
8. Pietsch, T.W. & D.B. Grobecker. 1987. Frogfishes of the World. Systematics, Zoogeography, and Behavioural Ecology. Stanford University Press. Pp. 420.
9. Wheeler, A. 1975. Fishes of the World. An Illustrated Dictionary. Ferndale Editions. Pp.366.