When a Dragon Eye goldfish develop an elegant tail (caudal fins) with the shape of a butterfly’s wings, its name are being superseded as Butterfly.

In this article I will attempt to capture the various caudal fin shapes and eventually, highlight and understand the characteristics of each tail type.

Everyone of us has a different interpretations of beauty, hence there is no right or wrong caudal length and shape. Nevertheless, goldfish have many variations in each spawn and it would be difficult to identify the entire type of butterfly. Hence, what gathered here are collections of my personal butterfly and hopefully I have address most of the butterfly available in the market.

Delta Tail

Delta Tail Butterfly are basically with the tail shaped like a triangle. The shoulders stretched out straight out on the two side. Some Delta Tail Butterfly shoulders thrust forward slightly.

Long Lobe Tail

As the name stated this tail has a long lobe shape which the length of the tail lobe are the same or slightly longer than the body length. Usually the shoulders are trust forward and arch back (downward) slightly. The edge (side) of the tail has an indentation. For some, the tips of the tail crossed each other due to the right lobe bending towards left and the left lobe bending towards right.

Long Lobe Tail Butterfly is generally likeable by hobbyists. Because of their long lope tail, they swim clumsily in the water, providing a joyful sight.

Tosakin Tail

The photo on the left shows a Japanese goldfish known as Tosakin. It’s popularity, no doubt due to its curly tail. The centre core of the tail is joined together as one complete tail. There is no slit. The tail shoulders trust forwards and twisted downward aggressively. The lines forming on the tail are regard as ‘Hundreds Folds’ by the Chinese, giving it a saw tooth appearance.

Tosakin Tail Butterfly is rare, but can be found. These are difficult to produce due to the balance problems from the added weight on the head. However, they are very unique and beautiful goldfish.

Trapezium Tail

Trapezium Tail Butterfly has a very narrow centre slit. For some Trapezium Tail, when the butterfly is in stationary, the centre slit is hardly seen. Some tail shoulders are adequately thrust forward.

The main different between this Trapezium Tail and Delta Tail is that the inclination of the tail edge (Purple line) between the corner of the tail shoulder (Green dot) to the tail tip (Blue dot) is not as sharp as Delta Tail butterfly.

Silk Tail

These tail usually form a shape of a semi circle. It is hard to find Silk Tail Butterfly with strong tail shoulders to hold and stretch the big tail.

Chinese tend to classify these Silk Tail Butterfly as ‘Soft Bone Tail’ Butterfly. Regardless of the shape, as long as the tail floats like a piece of silk in the water is a Soft Bone Tail. Although, Silk Tail butterfly does not have the elastic tail like the rest of the butterfly family, it sure does have its only graceful side and its own beauty.

Fiery Tail

Any butterfly with a WIDE slit opening in the centre and a board tail fin will come under this category. Among Fiery Tail butterfly, there are many minor variations like some shoulder tail are slightly curl down (photo on the left), sharp pointed tail tips (photo below), etc.

Fiery is defining as something ‘characterized by intense emotion’. This description fits Fiery Tail butterfly perfectly. Fiery Tail butterfly tend to swim in a emphatic stroke (forceful manner). Due to the wide but short tail, the tail seems to swing ceaselessly while gliding through the water. Like real butterfly polarizing the flowers.

Shuan Shu Tail

While most of the butterfly have tail fin largely stretches side ways and waist down (lower waist line), the unique thing about this butterfly is that huge portion of their tail fins actually extend above the waist level (upper waist line) of the fish.