Atherinidae are abundant and considered bony fish (teleost) that are widespread globally, living in rivers, estuaries, and coastal waters.

Overall, there are twenty-five species, of which twenty are freshwater organisms and five are marine fish found only in Australian coastal waters.

How Craterocephalus diverged from being marine water organisms is linked to the ancestors of Craterocephalinae and Atherininae, where both subfamilies lived in similar environments but were separated by a North-South disjunction around Australia.

The separation caused one lineage to remain in Northern Australia, forming the genus Craterocephalus, which developed distinct characteristics from the other subfamily Atherininae.

Freshwater fish in the genus Craterocephalus are found in various ecosystems, such as rivers, rainforest streams, creeks, and hot desert springs.

Characteristics of the fish include having short life spans that are 2–3 years long, and their body length ranges from 5–10 cm.

Maturity is reached when fish are 3–5 cm in length, and most species spawn shortly after one year of being born.

Spawning rates increase in the spring and continue to be high in the summer — typically, one fish releases 85 eggs daily.

[9] Craterocephalus stercusmuscarum is an Australian freshwater fish of marine origin that has moderate dispersal potential.

The species is abundant in the Wet Tropics of Northern Australia and travels long distances upland to areas near waterfalls.

One is Atherina, which is found near the Eastern Atlantic and Mediterranean oceans; however, the remaining four are restricted to Australia’s southern coastal waters.

[11] Atherina hepsetus is found in marine and brackish waters across the Eastern Atlantic coasts and can swim between 5 and 20 meters in depth.

The gonadosomatic index (GSI) for both males and females increases after August and remains high until December, indicating their breeding period is around these months.

Smaller fish are present throughout the year, which means that breeding occurs over a long period of time.

This species primarily lives in estuaries, so their breeding occurs there, but as the fish mature, they travel to the ocean and spawn there.

Spawning begins from August to November due to the GSI of the fish being significantly high in both males and females.