If you have ever had an aquarium at your home, then you might have crossed path with mollies and platys at any one time. These small but active fish may be well suited for any common home aquarium whether for the beginner or the advanced aquarist. However, the definition of their gender is slightly complex, especially in the anal fins section. Now it is time to discuss what makes mollies and platys unique and how to determine the sex of a fish by the shape of its fin, namely, the anal one.
Which Gender Of Mollies And Platys Has Fan-shaped Anal Fin?
What Are Mollies?
Mollies can be regarded as freshwater fish of the Poecilia family. They have been christened as friendly fish because they can adapt to different water conditions and are not considered aggressive. This is because mollies come in a variety of shapes and colors and are therefore preferred by many people.
What Are Platys?
Other types of aquarium fish that belong to the freshwater category are platys or platies, which are from the Xiphophorus genus. They are compatible with swordtails and are generally colorful fish that are relatively simple to maintain. Like the mollies, platys are livebearers and therefore give birth to live young ones and not lay eggs.
Physical Characteristics
General Body Shape
One gets lost trying to determine the difference between Mollies and platys due to the similarities in their physical outlook. Mollies have a long, slender body while the body of platys is shorter and relatively fatter. However, both are thin and long limbed which are important characteristics that help in swimming.
Color Variations
The other thing that both mollies and platys are known for is that it is possible to get them in varying color variations. Mollies can be black, white, orange or a mixture of all the three while platies have reds, oranges, yellows and blues. However, none of these colour differences are gender associated but are rather genetic and selective breeding.
The Anal Fin Explained
What is considered as the sex organ different from the male and female genitals?
The anal fin is situated towards the ventral surface of the fish, slightly behind the anus. It is perhaps important to note that in majority of fish, the anal fin is involved in stability and locomotion. In case of mollies and platys, it has another significance of gender determination as well.
Significance of the Anal Fin in Identifying Fish Species
To identify the gender of mollies and platys, the shape and size of the anal fin are quite crucial. This fin is not mere decoration and has assumed copulatory functions, particularly in males of the species.
Gender Differences in Mollies and Platys
Identifying Male Mollies
Male mollies have a special appendage instead of an anal fin called a gonopodium. This fin is elongated, thin, and tubular in shape, it seems like a stick rather than a fin. The gonopodium helps the male to transfer the sperms to the female during reproduction.
Identifying Female Mollies
As for the female mollies, they possess a more developed fan-shaped adipose fin on their ventral side. This is wider and more triangular shaped fin and does not contain any of the special structures seen in the males. The fan-shaped fin is not a modified pectoral fin which assists in reproduction of the fish but is important in swimming and balance.
Identifying Male Platys
Like male mollies, male platys also have a gonopodium on them. This modification of the anal fin is crucial not only for their duty in reproduction. They have a similar shape and function for both the species.
Identifying Female Platys
Female platys have a thin fan shaped anal fin similar to the anal fin of the female mollies. This broad, triangular fin is even more evidence of their gender and is helpful for telling them apart from males.
The Fan-Shaped Anal Fin
Which Gender Of Mollies And Platys Has Fan-shaped Anal Fin?
In both mollies and platys the colour varies between sexes where the females have a fan-shaped anal fin. This is one of the best methods that can be used to help identify the sexes in those species of animals. If you spot a fish with wide and flattened base of the anal fin, you are sure it is a female one.
Why is the anal fin of a fish fan-shaped?
A large fan-shaped anal fin in females is for balance and effectively swims in water. While the gonopodium in males is specially designed for reproductive purposes, the female’s anal fin is somewhat more typically shaped to allow the fish to swim and manouvere in its daily activities.
Guides to Identify the Sex of Mollies and Platys
Observing the Fish’s Behavior
Males and females can also be distinguished based on behavior patterns, although this may be a bit difficult. Males will frequently be more aggressive and display courting behaviors, for example chasing a female or other males. Studying these interactions can provide more information in case of identifying gender.
Physical Examination
To determine the gender of your mollies or platys, get to calmly observe them when they are not stressed. Bring special attention to the form of the anal fin. Bear in mind that the males have elongated, slender gonopodium and that the females have an anal fin that resembles a fan.
Common Misconceptions
Misidentifying Juvenile Fish
Another potential issue is sometimes the anal fins are not well developed in juveniles of both mollies and platys. Young males might not fully develop their gonopodium, which makes it a little difficult to distinguish between them and females. It is recommended that one should wait until the fish are a little older before coming into a conclusion as to the kind of fish it is.
Confusing Different Species
At times, mollies are mistaken for platies or other related fish species by aquarists who may be working with the fish. Though their body profiles and pigments can be quite similar, it is advisable to differentiate between the two based on anal fin shape and some other features.
Conclusion
It is important to understand the differences between sexes for both mollies and platys in order to have a better control over the aquarium and the breeding. By observing the shape of the anal fin, it becomes almost easy to point out the sexes’ difference. Oh yeah, male has got a gonopodium, the females have got a sort of a fan-like anal fin. Happy fish-keeping!
FAQs
What ought I to look for in order to know where my molly is at with pregnancies?
The pregnant mollies will have a clearly rounded belly, and often you may even see a black or rather dark colored patch near its anal fin, known as the gravid spot. They also get to withdraw from other people as they are expectations to give birth soon.
Can male mollies live with platies or do they become aggressive toward each other?
Generally, yes. Although these two species are generally not very aggressive, there are potential threats. But boy mollies and platys do become territorial particularly during breeding seasons. That is why it is wise to ensure that the environment contains many places where one can hide so that the two parties can avoid a confrontation.
When do mollies and platys reproduce or breed?
As for reproduction, mollies and platys are extremely prolific fish since females can drop litters every 4-6 weeks at most. Proper tank conditions can also help in the breeding if it is properly taken care of.
What type of food should I use for my mollies and platys?
Mollies and platys are somewhat similar in their feeding habits since the two fish are omnivores. High-quality flake food, augmented by living/frozen food such as brine shrimp and bloodworms, plus a little vegetation is all that is needed to maintain a healthy, bright stock.
What is the size variation of mollies and platys?
Mollies can grow to be 4-6 inches, while platys grow up to become 2-3 inches long. They can also have different stadial size according to the type of species and the habitat it lives in.
