PORT PHILLIP BAY


Globefish 

Diodon nicthemerus Cuvier, 1818

View scientific description and taxonomy

Scientific Details

Meristics.
Dorsal fin spines/rays: 12-13
Anal fin spines/rays: 12-14
Caudal fin rays: 9
Pectoral fin rays: 19-21

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.
The Tetraodontiformes is a very diverse and specialized group of bony fishes that share the loss, reduction or fusion of many bony structures in the head and body. Fins and their supporting elements are reduced or lost, and vertebrae are reduced in number. They have small mouths with modified teeth that may be enlarged or fused into a beak-like structure, or incorporated into the jaw bones. The gill opening is reduced to a small slit near the pectoral-fin base, and most have thick skin, covered in scales that are modified into spines, ossicles or fused bony plates. Some groups are poisonous, and the puffers and porcupinefishes are highly inflatable. Puffers and their allies are found worldwide in temperate and tropical seas, and a few species enter freshwaters.

Family level detail.
Medium to large-sized robust fishes, similar to pufferfishes, with bodies covered in large strong spines. They have small mouths with fused teeth forming a strong beak, slit-like gill openings and small dorsal and anal fins far back on the body. Porcupinefishes are slow swimmers and when alarmed, can inflate their bodies into spiny spheres.

Taxonomy

Phylum:
Chordata
Subphylum:
Craniata
Superclass:
Gnathostomata
Class:
Actinopterygii
Order:
Tetraodontiformes
Family:
Diodontidae
Genus:
Diodon
Species:
nicthemerus

General Description

Body robust, somewhat oval, brown to greyish on top, white below, covered in long white to yellow spines and 3-4 dark vertical bands or blotches on sides. The spines usually lay flat against the body. When threatened, globefish rapidly inflate themselves with water or air, causing the spines to stand erect. To 30 cm, although most grow to about 15 cm.

Biology

When threatened, Globefish greatly inflate their bodies causing their spines to stand erect from the body and becoming spiny "globes".

Habitat

Common and widespread in a range of habitats, preferring sheltered reefs, and often seen in weedy areas, around jetties and pier piles, in depths of 0-85 m.

Reefs

Seagrass meadows

Distribution guide

Southern Australia.

Species Group

Fishes › Porcupinefishes

Depth

Shore (0-1 m)
Shallow (1-30 m)
Deep ( > 30 m)

Water Column

On or near sea floor Midwater

Max Size

30 cm

Harmful

Spines on body can inflict injury.

Commercial Species

No

Global Dispersal

Native to Australia

Conservation Status

  • DSE Advisory List : Not listed
  • EPBC Act 1999 : Not listed
  • IUCN Red List : Not listed

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, Globefish, Diodon nicthemerus, in Taxonomic Toolkit for marine life of Port Phillip Bay, Museum Victoria, accessed 26 Jun 2025, http://136.154.202.208:8098/species/7988

Text: creative commons cc by licence