can you please describe this species?
A type of gun dog with a long silky coat and drooping ears, broad muzzle. The prevailing color is liver and white, sometimes red and white or black and white, and sometimes deep brown, or black on the face and breast, with a tan spot over each eye.
Spaniel
The "Oxford English Dictionary" defines Spaniel as "a breed of dog with a long silky coat and drooping ears".

Not much has changed about spaniels in general over the years, as can be seen in this 1921 entry in "Collier's New Encyclopedia":
Their distinguishing characteristics are a rather broad muzzle, remarkably long and full ears, hair plentiful and beautifully waved, particularly that of the ears, tail, and hinder parts of the thighs and legs. The prevailing color is liver and white, sometimes red and white or black and white, and sometimes deep brown, or black on the face and breast, with a tan spot over each eye. The English spaniel is a superior and very pure breed. The King Charles is a small variety of the spaniel used as a lapdog. The water spaniels, large and small, differ from the common spaniel only in the roughness of their coats, and in uniting the aquatic propensities of the Newfoundland dog with the fine hunting qualities of their own race. Spaniels possess a great sha
how big does a king charles cavalier get Historically the Cavalier King Charles Spaniel was a lap dog and is small for a spaniel, with fully grown adults comparable in size to adolescents of other larger spaniel breeds. did this species diverge from some other group? Yes - spaniel
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Spaniel [SEP] Definition and description
The "Oxford English Dictionary" defines Spaniel as "a breed of dog with a long silky coat and drooping ears". Not much has changed about spaniels in general over the years, as can be seen in this 1921 entry in "Collier's New Encyclopedia": Their distinguishing characteristics are a rather broad muzzle, remarkably long and full ears, hair plentiful and beautifully waved, particularly that of the ears, tail, and hinder parts of the thighs and legs. The prevailing color is liver and white, sometimes red and white or black and white, and sometimes deep brown, or black on the face and breast, with a tan spot over each eye.