Singletail

Singletail is a term that can refer to several different things, primarily in the realm of biology and zoology. One common usage is in relation to certain types of fish, specifically those belonging to the family Gobiidae, commonly known as gobies. These fish are characterized by having a single, undivided tail fin, distinguishing them from some other fish species that might have more complex or lobed caudal fins. Examples of fish that might be colloquially referred to as "singletails" could include certain species within the goby family found in freshwater or marine environments.

Beyond fish, the term "singletail" can also be used in entomology to describe certain insects. In this context, it might refer to the caudal appendages or cerci of insects, particularly when these structures are unbranched or reduced to a single, simple projection. This morphology can be a distinguishing feature for identifying specific insect species or groups. The specific meaning of "singletail" in entomology would depend on the taxonomic context and the particular insect being discussed.