All vertebrate animal research requires approval from your institution's animal care and usage committee. However, this is not necessarily true for invertebrates such as fruit flies (Drosophila melanogaster) and worms or nematodes (Caenorhabditis elegans).
All vertebrate animal research requires approval from your institution's animal care and usage committee. However, this is not necessarily true for invertebrates such as fruit flies (Drosophila melanogaster) and worms or nematodes (Caenorhabditis elegans).
I think it depend of the country where you live. In Ukraine not only invertebrates, but Amphibia and Reptilia (Anamnia) can used for experiments without permission of ethical committee. I think it is very bad situation.
I wonder if you are asking this question, because you want to find out which animals are not considered properly or because you want to avoid the ethics committee. The first is admirable if your aim is to affect change in the use of (different kinds of) animals in research. The latter raises the question of why you want to avoid an ethics committee, which is problematic.
Personally, I think much of the experimentation that uses animals nowadays is unnecessary and we should be moving to non-animal testing models. That is the ethical thing to do.
In our step, we have to take ethical clearance for any research even if there is no involvement of any living being. So in my opinion, there is no research involving animal for which there is no need for ethical clearance.
Presently, primates, mammalian and human clinical trial cases require ethical clearance. Fishes/Flies do not require, at the moment. However, while using transgenic models, Institutional BioSafety Committee clearance is required. I hope this info will helpful.
The fact that you are asking this question, I think, begs a few larger ethical questions: Why do you want to use animals which don't require ethical approval? Why do you want to use animals at all?
If you want an animal which will be 'easier' to do research on, because it requires less regulatory hoop-jumping, consider ethics review boards of all types are not there purely to hinder research - they are there to uphold a community standard of not only ethical treatment towards animals, but ethical research on a more general scale.
If you want to do research on animals that don't require ethical approval because they may be somehow 'less worthy' of ethical consideration, for example an invertebrate, consider the fact that there is growing evidence demonstrating pain perception in many animals once thought not to experience pain. Also consider cultural understandings of different species of animals across the world; what can you/we learn from other cultures regarding the significance, culturally, morally and ethically, of each and every animal?
Consider also the ethical need to replace animals with other models where possible; reduce the amount of animals needed to be used in research; and refine your procedures to minimise pain and distress to those animals. These are the questions and dilemmas faced by ethics review boards, but they must also be considered by scientists and the community at large as we consistently redefine bioethical boundaries.