Imagine: one half of the body is completely female, and the other is male. The vertebrates such a situation is quite rare (only birds are found at the moment), in insects - more often.
This anomaly, called the hynanderromorphism, is due to errors in the distribution of sex chromosomes during the ripening of the egg.
Detect the hynnidromorphism is the easier, the more pronounced by the type of sexual dimorphism. That is, looking, for example, on the butterfly, you can easily say - the male in front of you or the female. That is why such hynnandomorphs are easiest to notice.
Haninandromorphs are divided into three types: bilateral (longitudinal half of the body have different sexual signs), the front-rear (upper and lower half of the body have different half signs) and mosaic (various parts of the body carry signs of male and female).