I see a lot of comments of the spider being blatant black face. But given the pre-occupation timing of the art piece, I'm hesitant to label the tag onto this short. Is there any evidence that it indeed was an attempt at racial fear mongering? The parallels are certainly there to see, but I am reluctant to ascribe intent to a work of a time period I am not familiar with intimately.
However the racist stereotypical parallels are just too blatant to ignore. The spider is the literal definition of the "coon caricature" at work. The awkward contrast of the anthropomorphized ladybug having a typical Japanese
lady appearance and the Spider having a coon face and smoking a cigar reeks of war propaganda of the worst kind - an employment of racist and xenophobic fear mongering to rile up the masses.
The problem arises when it comes to ascribing intent. A lot of Japanese animators of this period were looking to Disney for inspiration and Disney itself was a terrible proponent of racist stereotypes in its own animated classics both before and after the time of this piece. As with other things that the animators took inspiration from, it is possible that they also acquired the coon caricature stereotype and the racist trope of the "black person who rapes the suburban woman" without realizing the poisonous connotation it carries. At the same time it is also possible that the animators recognized these issues and weaponized it for their own audience to consume.
As modern viewers of an art reflective of its time, we must not only observe the intent of the author and their authorship, but also the cultural ramifications in the context of consuming this art today. It is important to keep in mind that these tropes, intentional or otherwise are poisonous and perpetuate real harm in society today and we must understand and call it out without rushing to immediate black and white judgements.