Ray-finned fishes

Habitats

The following habitats are found across the Ray-finned fishes distribution range. Find out more about these environments, what it takes to live there and what else inhabits them.

• Sea bed
• Brackish water
• Deep ocean
• Estuaries
• Intertidal zone
• Lakes and ponds
• Shallow seas
• Open ocean
• Reefs
• Rivers and streams
• Swamp
• Rockpools
• Wetlands

Behaviours

Discover what these behaviours are and how different plants and animals use them.

Adapted to swimming
Adaptations for swimming enables animals to move around in water. Animals that can swim proficiently (natatorial) fall into three categories.

Fossil types

Learn more about the other animals and plants that also form these fossils.

Exceptional preservation
Normally, only the hard parts of animals and plants - shell, bone, teeth and wood - are preserved as fossils. However, every now and then conditions permit the preservation of soft parts and create treasure houses of information for palaeontologists.

About

The Actinopterygii ( /ˌæktɨnɒptəˈrɪdʒi.aɪ/), or ray-finned fishes, constitute a class or sub-class of the bony fishes.

The ray-finned fishes are so called because they possess lepidotrichia or "fin rays", their fins being webs of skin supported by bony or horny spines ("rays"), as opposed to the fleshy, lobed fins that characterize the class Sarcopterygii which also, however, possess lepidotrichia. These actinopterygian fin rays attach directly to the proximal or basal skeletal elements, the radials, which represent the link or connection between these fins and the internal skeleton (e.g., pelvic and pectoral girdles).

In terms of numbers, actinopterygians are the dominant class of vertebrates, comprising nearly 96% of the 25,000 species of fish (Davis, Brian 2010). They are ubiquitous throughout fresh water and marine environments from the deep sea to the highest mountain streams. Extant species can range in size from Paedocypris, at 8 millimetres (0.31 in), to the massive Ocean Sunfish, at 2,300 kilograms (5,100 lb), and the long-bodied Oarfish, to at least 11 metres (36 ft).

Read more at Wikipedia