Subspecies

A subspecies is a rank below species.

Below subspecies
In many scientific circles there is no rank below subspecies. However, one can occasionally find words that hint that they are, or are otherwise a category that wold cause a dispute for a subspecies ranking.

Ecotype: This is a word that describes a type within a species that is specifically adapted to a particular environment. It seems to be an alternative to other words such as subspecies, race, and "unique" population. It seems that it is used to select a particular population o

This could include a known subspecies of an animal. If animal S usually lives in deserts, then Sa is its more accepted form that lives in a large desert across a continent, but its Sb form lives in a rainforest. It could be a replacement for subspecies if the scientist disagrees with the notion of subspecies or how it's handled. For example, S lives in a desert, and this is its accepted habitat. But Sb, Sc, and Sd are different subspecies that all live in the same large rainforest, but have different adaptations. Therefore the scientist will call them an "ecotype" and feel that despite the various population anomalies

Polymorphism: Polymorphism is when a species in a certain locality has more than one allele at a locus. This means that there is a trait that has a common variant. For example, two or more different color phases of an animal in the same jungle.

Polyphenism: These are factors of a species that result in differences as a result of their environment. These factors are based in how the child was reared. However, they are not fixed evolutionary mutations of the population. For example, if the young of a creature grow up in stress-filled environment, they will form a defensive part of their body. This change is fixed in their bodies for the duration of their lives (or the form that their in, in the case of insects and amphibians).

In the past, polymorphism would have been used to indicate a subspecies separate from another, including those that live in the same local environment. Alternatively, if the two colors regularly interbred and litters would have multiple colors, this would likely be closer to a phase. According to wikipedia, in order to have polymorphism, the matings have to be in the same environment and totally random. That means free from other factors such as ranking,

other sub-rankings or ranks higher than subspecies but below species. An ecotype is an animal group that has been adjusted to a certain environment through adaptation. According to Wikipedia, an ecotype is a group of animals within a species that have been adapted to a certain environment. If you have an animal with a diverse range of environments, this would mean that each population would be an ecotype.

Logically, this could be a single subspecies, miltiple subspecies, or a group of "sub"-subspecies.