| Dalhousie hardyhead | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Atheriniformes |
| Family: | Atherinidae |
| Genus: | Craterocephalus |
| Species: | C. dalhousiensis |
| Binomial name | |
| Craterocephalus dalhousiensis | |
The Dalhousie hardyhead (Craterocephalus dalhousiensis) is a species of silverside in the family Atherinidae. [1] It is endemic to the warm waters of Dalhousie Springs in the Lake Eyre basin, Australia, along with the similar Craterocephalus gloveri . [2] It inhabits shady areas in tropical freshwater streams at 20-39 °C, but has been recorded at 41.8 °C. Its food consists of gastropods, aquatic plants, green filamentous algae, detritus and small invertebrates; food is mainly taken from the substrate. [3]
The species is generally golden brown with a darker brown back. A dark midlateral band runs from the snout to the base of the caudal fin. Two to three rows of pigmented scales form discontinuous lines below the midlateral band. [4] It is the only species in the genus Craterocephalus known to be sexually dimorphic. [2] Adult males are smaller and exhibit a rounded belly compared to the flattened belly of females. Males also lack the forehead concavity exhibited by females. [4]
As of July 2024 [update] , it is listed as critically endangered under the EBPC Act. [5]
