However, there are multiple forms of albinism – currently seven types recognised for humans – most of which do not result in red or pink pupils.The term "partial albino" is sometimes used in the literature, however, it has been stated that "A common misnomer is partial albino – this is not possible since albinism affects the whole plumage of a bird, not just part" and the definition of albinism precludes the possibility of "partial albinism" in which a mostly white bird shows some form of melanin pigmentation. "It is simply impossible, just like being partially pregnant ". Conditions that are commonly termed "partial albino" include neural crest disorders such as piebaldism, Waardenburg syndrome, or other depigmentation conditions such as vitiligo. These conditions result from fundamentally different causes to the seven types of oculocutaneous albinism that have been identified in humans (and confirmed in some other animals) and the use of the term "partial albino" is therefore misleading.One definition states that "albinism, (from the Latin albus, meaning "white"), hereditary condition characterized by the absence of pigment in the eyes, skin, hair, scales, or feathers", however, this does not encompass invertebrates, nor does it include plants. Furthermore, it could be interpreted that "...absence of pigment..." does not include an absence of structural colours. The lack of clarity about the term is furthered when the name of an animal includes the term "albino" although the animals (clearly) do not have the condition.
In Sarcopterygii
Albinism in the African lungfish has been reported on at least two occasions. In reptiles
Many reptiles labeled as albino are, in fact, not completely lacking in all colour pigments. They are actually amelanistic, not albino. Reptiles often possess at least two pigments. Among the most common are xanthin (yellow) and erythrin (red). An amelanistic reptile therefore, may still have pale yellow, orange, or red pigmentation. The California Academy of Science, in the Steinhart Aquarium, as of 2015, has on display an albino American alligator named "Claude". The alligator is partially blind because of lack of pigment in its eyes. The albino alligator hatched from the egg in 1995 in Florida, and was brought to the academy in 2008. This alligator would not have survived in the wild because its whiteness would have made it too easy a prey object. The only known albino alligators are in captivity. While extremely rare, white-coloured crocodiles and alligators do exist in other places. However, most of these animals are leucistic given that they have a general loss of pigmentation with some colour tinges remaining on their bodies although looking at first like other albino creatures, thus creating the misconception that the reptiles are albino themselves when they are not. Four such alligators are kept at the Gatorland theme park in the U.S. state of Florida. In Australia, a crocodile believed to be "part-albino" and nicknamed by people in the area as "Michael Jackson", attacked and killed a man.In snakes, partial absence of pigment is more common than absolute albinism.