Green Sunfish vs Warmouth – What Is The Difference

By Get Fishing •  Published: 01/24/23 •  6 min read

If you’re not totally familiar with the wide variety of fish in the Sunfish family, it’s easy to get them confused. The Green Sunfish and Warmouth, in particular, look very similar. In this post we’ll discuss how to tell them apart and know what species is on your line. 

Green Sunfish vs Warmouth

Is a Green Sunfish the Same as a Warmouth?

No, a Green Sunfish is not the same as a Warmouth. These are two separate species, but even mid level anglers may confuse them. The two fish look similar enough in appearance that you might have to squint to tell the difference. They both belong to the Sunfish family.

What’s the Difference Between Green Sunfish vs Warmouth?

The main difference between these two species is their habitat preferences and distribution. There are also some differences in appearance as well, although you might need a sharp eye to tell them apart. 

What is a Green Sunfish? 

green sunfish

The Green Sunfish (Lepomis cyanellus) is a freshwater fish found in North America. They belong to the Sunfish family and are both carnivorous and aggressive. Green Sunfish are also considered panfish due to their size. 

This species is often confused with the Bluegill, as well. An overlap in habitat and distribution often makes it tough for fishermen to tell species in the Sunfish family apart.  

What is a Warmouth? 


The Warmouth (Chaenobryttus gulosus) is an aggressive freshwater fish, also belonging to the Sunfish family – and therefore related to the Green Sunfish. Warmouth also go by the names Redeye, Goggle-eye, Stump Knocker, Rock Bass and more. They’re often confused with the Rock Bass, a completely separate species despite the shared common names. 

How to Tell the Difference Warmouth vs Green Sunfish

how to tell the difference between a green sunfish and a warmouth

Despite the shared family tree, these two species differ in quite a few ways. First, in terms of appearance, here are some of the key areas you can use to tell them apart:

Habitat and distribution will also make it much easier for you to tell which fish you’ve caught, and we’ll explore that further on. 

Green Sunfish vs Warmouth Size Differences

The Green Sunfish averages anywhere from 3-7 inches in size and usually weighs less than a pound. The size of the Green Sunfish is what makes it the perfect panfish, aka, the perfect size for frying up in a pan.

The Warmouth can range from 4-10 inches on average, but has been known to easily hit 12 inches depending on their habitat. They can weigh up to 2.25 lbs. This makes them a bit too large to be considered a panfish, but their bigger size makes them a fun fish to reel in with more fight. 

Green Sunfish vs Warmouth Dorsal Spines

These species share similar dorsal fins, however there are some differences that might pop up and can steer you in the right direction.

The Warmouth has 10 dorsal spines on average along their back. They may have as few as 9. The first half are spikey, with the second half of the fin rounded off. 

Green Sunfish also have 10 dorsal spines, although they may have as many as 12 – never fewer than 10. The second half of the dorsal fin is rounded as well, but a little higher than that of the Warmouth. 

Green Sunfish vs Warmouth Anal Fin Spines

Warmouth and Green Sunfish both have three anal fin spines. The Warmouth’s anal fin is more rounded, whereas the Green Sunfish has a more triangular shape to it. 

Green Sunfish vs Warmouth Coloration Differences

Adult Warmouths are dark in appearance and mottled brown with golden or lighter brown bellies. Males can be easily identified by the bright orange spot on their dorsal fin. Their gill flaps are red and they have reddish-brown streaks radiating out from their eyes. 

The coloration of the Green Sunfish is given away by its name – this species is a blue-green in color with yellow coloration on the ventral sides. Blue stripes appear near the eye and gill cover, which is why they’re often confused with Bluegill. Green Sunfish have a dark spot on their dorsal fin. 

Where Can You Find Warmouth? 

Warmouth are found on the eastern side of the United States, near the Mississippi drainage. They span from the Great Lakes up north, east to Pennsylvania, south to Florida, and over to the Gulf of Mexico.  

Warmouth Fishing Tips

What is a Warmouth

Warmouths are aggressive fish and will go after bait fast and hard. Make sure you have live bait or lures that mimic some of their favorite prey: crayfish, insects, and other small fish. 

Warmouths are also ambush predators and will strike from covered areas, in thick vegetation and near downed logs. Make sure you’re carrying gear that can handle a stronger fish and heavy vegetation. 

Where Can You Find Green Sunfish?

Green Sunfish are found mostly through the midwest of the United States. Like the Warmouth, they hang out around the Mississippi River, but move west into the Rocky Mountains and the Hudson Bay area of Canada. They can also be found in Northern Mexico. 

Green Sunfish Fishing Tips

What Is A Green Sunfish

Due to their small size, Green Sunfish usually go after insect larvae and insects. They’ll also eat crayfish, snails, and small molluscs as well as fish eggs. Look for live or artificial bait that mimics any of the above. 

Habitat goes a long way in landing a Green Sunfish. This species loves shallow water with sandy or gravel bottoms, so make sure your rig can stand up against getting caught up on underwater outcroppings. They’ll hang out near rocky overhangs, heavy vegetation, and submerged logs. 


Hopefully this post has given you the tools to go out there and easily identify both the Green Sunfish and the Warmouth. While these fish might look similar at first glance, they have a few distinct characteristics and very specific preferences when it comes to habitat and distribution. Happy fishing!

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