News / Species Spotlight / Species Spotlight - Crested Weedfish (Cristiceps australis) (07/19/17)

Species Spotlight - Crested Weedfish (Cristiceps australis)

Species Spotlight - Crested Weedfish (Cristiceps australis)
The southern coastline of Australia has a highly unique marine fauna that is often quite different from what we find on tropical coral reefs. The waters here are cool and nutrient-rich, and for this reason we find a proliferation of algae, rather than the stony corals which dominate in warmer climes. Some of Australias most iconic fishes, like the charismatic Weedy and Leafy Seadragons, come from these algal ecosystems, and one of the most characteristic inhabitants in this watery realm is the Crested Weedfish (Cristiceps australis).

Weedfishes belong to the family Clinidae, which numbers around 86 species. These fishes are not a familiar group to aquarists, as most species occur in subtropical or temperate habitats which typically see little collection. They are close relative of the blennies, but differ in having small scales, versus the scaleless blennies, and a dorsal fin that has more spines than rays. Southern Australia is particularly blessed with clinid biodiversity, with around 40 species endemic to these waters. South Africa has a similar number of species, which are given the Dutch name Klipfish, or kelpfish. Elsewhere in the Indo-Pacific the group is quite uncommon, generally being found only in cooler areas where algal growth is prolific. One of only tropical members of this group is Springeratus xanthosoma, a smaller species found throughout the West Pacific which is occasionally collected for the aquarium trade.

Cristiceps includes just three species, all from Australia. The Crested Weedfish is the most widespread of the bunch, occurring from Perth in the west to Sydney in the east. There is also the Silver-sided Weedfish (C. argyropleura) and the Golden Weedfish (C. aurantiacus), both of which are limited to Southeastern Australia. All are quite similar and reach around 7-8 inches in length. Coloration can be highly variable within these species, as they are highly adept at blending in with whatever algal species is dominant.

Unlike most of the true blennies, which tend to feed on algae, the weedfishes are carnivores which prey upon the many invertebrates and juvenile fishes associated with algal ecosystems. This makes them quite easy to feed in captivity, but, it should go without saying, a strong chiller is required to keep things adequately cool. Interestingly, clinids are live-bearing fishes. Maternal investment is among the highest of any fish, as measured by the growth of the embryos within the mother. But even with all this growth taking place internally, the juveniles still have a brief pelagic stage of a few weeks duration before they eventually settle down to the ocean bottom to live among the seaweeds.