So after a fun little side-discussion in another user's thread about his honey gouramis, I thought since there's so much confusion both in stores and among hobbyists about which gouramis are true honey gouramis and which are actually a different species, I'd help define the distinction.
True Honey Gouramis have the scientific name Trichogaster Chuna (formerly Colisa Chuna). They can be sold as Honey Gouramis, Honey Dwarf Gouramis, Sunset Honey Gouramis, or Gold Honey Gouramis.
This is the classic selectively-bred gold colorway for honey gouramis:
The top is a male, and the bottom is a female.
Now, things start to get really confusing when we look at wild-type honey gouramis or "sunset" honey gouramis. Sometimes Sunset honey gouramis are a different name for a vivid strain of gold honeys, and sometimes they're just another name for wild-type honey gouramis. They can look like this pair:
Or they can look like this:
In-store, the latter pair are wild type honey gouramis, and to make things really insanely difficult males and females will both look drab and silver when you look at them at your LFS. They can both have a stripe down their sides and their colors can change in a flash. If you ever decide to go for wild-type honeys, keep it in mind that it's extremely difficult to sex accurately in store and you may not know what you get until you take them home.
Everythings gets to be a bigger jumbled mess when we account for the mislabeling of other species. The most common confusion is with Trichogaster Labiosa or the "Sunset" colorway of the Thick-Lipped Gourami (note: i actually love the wild coloration but it's impossible to find in the US!). Sometimes, you'll see labels like Red Honey Gouramis or Sunset Gouramis in the store. Sometimes they will be explicitly called honey gouramis. The only way you can tell the difference between Thick-Lips and Honeys is by taking a good look at them. Honeys will always be diminutive and oval-shaped. Honeys will always have color in their caudal fins. Thick-lips have a deeper body, more prominent lips, and clear to mottled caudal fins. Like so:
The above image is a male sunset honey gourami. When fully colored and grown, they can range from a deep orange to a ruddy red-brown. They could get speckled with black, too. This image is of a female:
Females tend to be a little lighter in color, and their dorsal fins are much more rounded. Dorsal fins in males extend to a long point.
So if you look at a 'sunset' gourami or a 'red honey' gourami and see that clear-to-white caudal fin, it's pretty much guaranteed to be a thicklip gourami variation.
Knowing which species you have can help guide hobbyists to purchasing the correct species as mates for a tank. It can also help with gauging stocking levels and how many can fit in a space. Honeys can happily live their lives in a 10 gallon tank, because they only grow to two inches, and the are quite calm and peaceful fish. Thicklips, while very peaceful, can grow to reach a beefy 3.5 to 4 inches, and need at least 15 gallons of space or they will get cranky. Thicklips tend to be less shy and more outgoing, and as they grow, they are more likely to exhibit minor aggression.
Hope this helps with identifying true honeys!