Correct terminology???

Magnum Man

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So I’m sitting here at 1st light, drinking my caffeine, and watching my tanks, and my pet store mutt ( angel ) has the longest “stabilizers” of any fish I’ve seen… and I don’t know what they are actually called… are they technically pectoral fins??? While I’m thinking, what are the whiskers on some Gouramis called??? Not sure if they are used the same, as the gourami’s is more hair like, and the angel’s is more fin like???
 
I had to get up, to take this picture, so I confirmed they still have pectoral fins, so the long things aren’t a modified pectoral??? I had thought of this before, that I never hear those used in conversation, to where I’ve picked up on what they are called…
IMG_6143.png
 
The 'feelers' of gouramis are their pelvic fins and angelfish long dangly fins are also pelvic fins.

Fish have -
dorsal fin - the one on their backs
pectoral fins - the ones near their gills
pelvic fins - the pair under the front of their body
anal fin - single fin on the underside near the tail
caudal fin - on the tail

Some fish have modified fins. With gouramis they have normal dorsal, pectoral and tail fins. The pelvic fins are modified to 'feelers' and the anal fin spreads along the whole underside of the body. Other fish have two dorsal fins; tetras have a dorsal fin and a second tiny fin on the back called an adipose fin, livebearers have a modified anal fin called a gonopodium.
 
So on the picture of the angel you can barely make out a normal pectoral fin... so the "long dangly fins" are technically a split pectoral??? ( sorry, I was corn fusing pectoral & pelvic fins... noticed it, when looking at the Cupid, also in the angel picture, & going back to @Essjay 's original post... ) so they are not pectoral fins, but are pelvic fins )

and if the "feelers" on a gourami, are their pectorals, do they still have a "normal" pectoral as well??? the only gourami I have right now, is a Kisser, & they don't have the feelers, so I can't look at that one...
 
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The 'feelers' of gouramis are their pelvic fins and angelfish long dangly fins are also pelvic fins.

Fish have -
dorsal fin - the one on their backs
pectoral fins - the ones near their gills
pelvic fins - the pair under the front of their body
anal fin - single fin on the underside near the tail
caudal fin - on the tail

Some fish have modified fins. With gouramis they have normal dorsal, pectoral and tail fins. The pelvic fins are modified to 'feelers' and the anal fin spreads along the whole underside of the body. Other fish have two dorsal fins; tetras have a dorsal fin and a second tiny fin on the back called an adipose fin, livebearers have a modified anal fin called a gonopodium.
To expand on this, some fish also exhibit a fin between the dorsal fin and caudal fin, called the adipose fin! It is present in many catfish, tetras, etc
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I've taken this diagram from here https://fisharticle.com/fish-fin-types-anatomy-functions/
fins.jpg


In gouramis and angelfish the feelers/dangly things are modified pelvic fins. If you look at angelfish, the only fin on the underside is the anal fin which, like the dorsal fin, has become elongated. In angelfish there is no pair of normal fan shaped fins under the body because they've been modified into the dangly things.
Similarly, gouramis have no obvious pair of pelvic fins because they're modified to become the feelers. And in gouramis, the anal fin has expanded forwards so that it now fills the underside of the fish.
 
Thanks, I just never knew what to call them... now if I'm talking Angel, or Gourami's, & I say Pelvic fins, people will know I'm talking about the long dangly things ;)
 
Rainbowfish and perch normally have 2 dorsal fins. The first dorsal fin is closest to the face.

The tail (caudal fin) is joined to the body at the caudal peduncle (the rounded end of the body where the tail fin rays come out).

Male saltwater sharks and stingrays have modified pelvic fins called claspers.

Male livebearers have a modified anal fin called a gonopodium.
 
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Other fish have two dorsal fins; tetras have a dorsal fin and a second tiny fin on the back called an adipose fin, livebearers have a modified anal fin called a gonopodium.
To expand on this, some fish also exhibit a fin between the dorsal fin and caudal fin, called the adipose fin! It is present in many catfish, tetras, etc

Only a select few types of fish have adipose fins, including salmonids (salmon, trout, etc.) and some larger catfish.

An adipose fin is called that because it is fleshy and fatty. It has adipose tissue in it.
The fin that you're describing on tetras and other tropical fish is not fatty at all, so it's not an adipose fin. Rather, it would simply be called the second dorsal fin.
 
Only a select few types of fish have adipose fins, including salmonids (salmon, trout, etc.) and some larger catfish.

An adipose fin is called that because it is fleshy and fatty. It has adipose tissue in it.
The fin that you're describing on tetras and other tropical fish is not fatty at all, so it's not an adipose fin. Rather, it would simply be called the second dorsal fin.
See I've seen it referred to adipose even among tetras, with separating some genus and species apart

Screenshot_20240903_142742_Samsung Internet.jpg
 
See I've seen it referred to adipose even among tetras, with separating some genus and species apart
Alright, my bad, I looked into some scientific literature and the term is indeed used for fish other than salmonids/catfish. My guess is that even though these fins are not fatty in the vast majority of tropical fish, the term "adipose" might have been applied here because they don't have the same types of fin rays as all the other fins, so they are fleshier than the others.
 

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