The plakat Trilogy!  

We currently have three PKs types which are accepted at the different shows around the world. In this article I would like to share my personal view on the different types of shortfinned bettas we know today. I hope this article will give you more insight in the different PK types and their standards. Please keep in mind that this article will partly overlap with the current IBC standards for PKs.

This article was published in:
- Flare (Journal of the IBC) - September/October 2007, Volume 41, No. 2.
- Le Macropode (Journal of the CIL) - January/February 2008, No. 1


Shortfinned bettas have gained much popularity in the betta world because of their compact, vital appearance. They often also have the advantage above longfinned bettas that they are better able to carry their finnage throughout their live and are less prone to finrot. Shortfinned bettas, also known as plakats are finnage-wise the closest related to the wildtype form. For ages, Thai breeders bred this form from wild caught bettas in order to develop its fighting nature, style, hardiness, size and color. This practice of selective breeding stood at the base of the different colors and tail types we know today.

It was the selective breeding of Guy Delaval (France) in the 80s, with fish originating petshops, Paris Jones (USA) and Peter Goettner (USA),  which gave rise to bettas with an increased caudal spread (up to 180 degrees). Since the cover of FAMA magazine in 1993 showed a picture of a turquoise halfmoon (HM) male, which was bred by the international CHENMASWIL partnership consisting of Laurent Chenot (France), Rajiv Massilamoni (Switserland) and Jeff Wilson (USA), the D-shaped caudal conquered the betta-world! In the years to follow the HMs were further perfected leading to the standard we know today. This development also had its effect on the evolution of other tailtypes. Nowadays the standards of both singletail as doubletail fish ideally describe a D-shaped caudal. But keep in mind that there is more than only the caudal and that the ideal HM is characterized by an overall balance which can be captured in a circle.

IBC Convention 1993 Tampa, Florida [1]
The ideal HM according to Yia Ly (France) [2]

For many years traditional plakats were the only type seen at betta shows but the HM fever also led to the evolution of the shortfinned tailtype. Crossing longfinned HMs to traditional PKs led to the development of the halfmoon plakat (HMPK). Like the traditional PK, the form of the HMPK is asymmetrical but combining traits of both traditional PKs and HMs. In 2005 the IBC officially distinguished (asymmetrical) traditional PKs and asymmetrical show PKs by creating a separate standard for both forms. Both standards show great overlap but differ in two essential points: the caudal and dorsal finnage.

When breeding longfinned HMs the ultimate goal is a fish with a balanced appearance, isn’t it therefore strange that the standard for HM PKs was describing an asymmetrical fish? Logically, the increasing interest in show plakats lead to the development of another type of PK, the symmetrical PK, the shortfinned equivalent of the longfinned HM also often reffered to as “shortmoon”. The IBC responded on this trend by the development of a trail standard and can be considered to be the shortfinned variant of the standard used for longfinned HMs.


The expansion of one PK class into three PK classes off course can create some confusion. So what are the similarities and differences between these standards?

Overall appearance: As the name already indicates, asymmetrical (traditional) and show PKs have an unbalanced appearance mostly caused by the length of the ventral fins and the shape of the anal fin. Symmetrical PKs on the other hand have a balanced appearance and ideally can be captured in an oval.

Body: The bodyshape in all three PK types is more or less similar. It is important that the body matches the finnage of the fish. Ideally the body should have a full volume with a strong peduncle. The “mouth-to-dorsal” topline should be smooth without dips and bumps. The back of the body should be nearly symmetrical (almost like a mirror image when one would draw an imaginary midlateral line) with a strong peduncle. The scaling on the body should be nicely aligned.

Black (asymmetrical) traditional PK male [3]

Caudal: In all three PK types the spread of the caudal ideally should be 180 degrees but the differences lie in the shape and branching of the rays. The caudal of (asymmetrical) traditional PKs is allowed to be rounded or spade-shaped. In my personal opinion the ideal (asymmetrical) traditional PK should have a primary (2-ray) branching. According to the IBC standard both a primary as a secondary (4-ray) branching are allowed. The spread in the caudal is not caused by an increase of branching but by an increase of webbing between the rays. The caudal of both asymmetrical show PKs and symmetrical PKs have straight rays, sharp edges and the shape of a semi-circle (capital “D”). The rays in the caudal often have a secondary branching (4-ray) or more (but should not be excessive). A >180 degree spread (overhalfmoon, oHM) is not preferred above a 180 degree spread. Here, the caudal should be no longer than 1/3 of the body.

Dorsal: In all three types, overlap of the dorsal with the body is not desirable and the front rays (near the head) can not be too short (as often seen in fish carrying DT). The dorsal of (asymmetrical) traditional PKs has the shape of a half/semi-circle with a possible slight pointed appearance and has a full volume. The dorsal of asymmetrical show PKs should be semi-circular and preferably snap open as a fan. The capacity of the fin to open in this fashion is often achieved not by increase in volume, but by an increase in fin ray branching. In symmetrical PKs the dorsal fin is usually a bit rectangular but it is important that the shape and size both do not disturb the overall balance. The desired effect is typically achieved by an increase in the number of fin rays.

Metallic blue asymmetrical show PK male
Copper asymmetrical PK male [4]

Anal: The anal starts at the thickest point of the body (just behind the stomach) and continues towards the peduncle. In the most ideal situation the anal overlaps the lower part of the caudal during flaring. In (asymmetrical) traditional PKs, the anal fin has the shape of a trapezium with the short part in the front and the longer part in the back which runs into a clear pointed tip. The length of the last ray is usually about 2 times the lower part of the caudal. The shape of the anal in asymmetrical show PKs is quite similar but lacks the clear pointed tip which is not desired here. In symmetrical PKs the anal is expected to be more rectangular and runs parallel to the body. The length of the rays is more or less the same and is equivalent to that of the lower part of the caudal and height of the dorsal in order to maintain the overall balance.

Ventrals: The ventral fins of (asymmetrical) traditional PKs can be either full or thin. The length should be minimal 2/3 the length of the body (as measured from the base of the ventral fin to the caudal peduncle) or longer.  The ventral fins of asymmetrical show PKs should be of same length but preferably should have a full appearance. In contrast to both asymmetrical PK types, the ventrals of symmetrical PKs ideally should be in full balance with the length unpaired fins in order to preserve the symmetrical appearance.

Black copper dragon symmetrical show PK male [4]
Blue/red multicolor symmetrical PK male [5]

Keep in mind that the three classes for PKs are pointing out the ideal situation. In real life the existence of three classes for PKs also creates difficulties. This especially in classifying fish for shows. Crosses between the different PK types or longfinned fish often also give rise to “in-between-forms” which are often reffered to as “transitional PKs”. The existence of three different PK classes logically leads to two types of "transitional PKs":
1) "Transitional PK type 1" is an in-between-form of traditional PKs and asymmetrical show PKs. The caudal of this type usually shows
multiple branching (varying from 4- to 8-ray) as seen in the caudals of asymmetrical show PKs but the edges are usually rounded which reminds us of the caudal of the (asymmetrical) traditional PK. The anal is often also is in is less pointed as in the (asymmetrical) traditional PK but longer as in the asymmetrical show PK.
2) "Transitional PK type 2" is an in-between-form of asymmetrical show PKs and symmetrical PKs. The difficulty lies here in the shape of the dorsal, anal and ventral fins. The dorsal is usually rectangular shaped. The anal is less sloped as in asymmetrical show PKs and but also less parallel than in the symmetrical PKs. The ventrals usually also have a length in between both forms. 
|In general,
these fish usually do not make it to top placings in either class but are often good material to work with and to build a nice line.

Dragon "transitional PK type 1" male
Metallic blue "transitional PK type 2" male



I hope you enjoyed reading this article and that this has given you a bit more insight in the different types of PKs which are currently found in the betta-scene throughout the world.


1. FAMA magazine
2. Yia Ly

3. Dong


4. Rung Keereelang (Banleangbettas)
5. Morris Gabriel


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