PORT PHILLIP BAY


Bigbelly Seahorse 

Hippocampus abdominalis Lesson, 1827

View scientific description and taxonomy

Scientific Details

Meristics.
Dorsal fin spines/rays: 27-30
Anal fin spines/rays: 4
Pectoral fin rays: 14-16
Body rings: 12-13 + 44-48
Subdorsal rings: 4-5 + 1-2

Interpreting fin count meristics.
Spines are in Roman numerals and soft rays are in Arabic numerals. Spines and rays that are continuous in one fin are separated by a comma. Fin sections are separated by semicolons.

Detailed descriptions of fin count and other meristics are in:
Gomon. M.F., Bray, D.J. & Kuiter, R.H. (eds) (2008) Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp.

Order level detail.
Mostly long, slender fishes with a small mouth at the end of a long tubular snout, although some species are deep-bodied. All are partially or completely encased in bony rings or dermal plates. Most are cryptically-coloured and often have dermal appendages providing further camouflage.

Family level detail.
A large and diverse group of pipefishes, seahorses, seadragons and pipehorses. All have semi-flexible bodies encased in bony rings and a tiny mouth at the end of a tubular snout. They lack fin spines and pelvic fins, and other the fins may be reduced or absent. Syngnathids have a unique reproductive mode. The sexes are separate and females deposit their eggs into special abdominal brood pouches or onto modified exposed regions under the trunk or tail of their male partner. The males incubate and nourish the developing embryos until they hatch. These extraordinary cryptic fishes are extremely well-camouflaged and often ornamentation such as filaments and other appendages on their bodies to closely resemble their surroundings.

Taxonomy

Phylum:
Chordata
Subphylum:
Craniata
Superclass:
Gnathostomata
Class:
Actinopterygii
Order:
Syngnathiformes
Suborder:
Syngnathoidei
Family:
Syngnathidae
Genus:
Hippocampus
Species:
abdominalis

General Description

Body compressed with a large abdomen, completely encased in bony rings; snout relatively long, tubular; tail long, prehensile; top of head often with filaments. Coloured to match surrounding sponges and macroalgae - usually yellowish, to red and brown, often with irregular darker spots and a broadly banded tail. To 30 cm.

Biology

Bigbelly Seahorses often cling to sponges, macroalgae such as kelp holdfasts, and other structures on reefs. They are the largest and most common seahorse in southern waters, and are locally abundant in some areas, including under piers in Port Phillip Bay.

Habitat

A range of habitats from low rocky reefs in shallow estuaries, to deep tidal channels and deeper coastal reefs, in depths of 0-100 m.

Reefs

Distribution guide

New Zealand and south-eastern Australia.

Species Group

Fishes Seahorses, pipefish and allies

Depth

Shallow (1-30 m)
Deep ( > 30 m)

Water Column

On or near sea floor

Max Size

30 cm

Diet

Carnivore

Commercial Species

No

Global Dispersal

Recorded in Australia

Identify

Conservation Status

  • DSE Advisory List : Not listed
  • EPBC Act 1999 : Not listed
  • IUCN Red List : Data Deficient
  • Fisheries Act 1995 : Protected Aquatic Biota

Author

article author Bray, D.J.

Di Bray is a Senior Collection Manager of ichthyology at Museum Victoria.

Author

article author Gomon, M.F.

Dr. Martin Gomon is a Senior Curator of ichthyology at Museum Victoria.

citation

Cite this page as:
Bray, D.J. & Gomon, M.F., 2011, Bigbelly Seahorse, Hippocampus abdominalis, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 20 Sep 2014, http://portphillipmarinelife.net.au/species/7994

Text: creative commons cc by licence