Stegmann's original writings on atlantis Gulls
Source:Stegmann, B, (1934), Ueber die Formen der grossen Möwen (subgenus Larus) und ihre gegenseitigen Beziehungen, Journ. f. Ornith. 82: 340-380.
page 373 for atlantis entry
Stegmann's work on gulls was very thorough and like Dwight's was based on a systematic study of skins. The entry for atlantis appears to owe quite a lot to Dwight except for the classification as a race of argentatus (Larus argentatus atlantis); michahellis is classified at the same level (Larus argentatus michahellesi).
The range of atlantis is given as:
Azores, Madeira, Canaries, Cape Verde, coast of Portugal and Atlantic coast of Morocco.
So the range is that of Dwight plus Portugal and is almost identical to that of Southern Atlantic Yellow-legged Gull (Southern atlantis) in the present study.
Note the article:
Dubois, P J, (2001), Atlantic Islands Yellow-legged Gulls, an Identification Gallery, Birding World, 14(7) 293-304
does not cite Stegmann's work. In:
Yésou, P, (2002), Trends in Systematics, Systematics of Larus argentatus-cachinnans-fuscus Complex Revisited, Dutch Birding 24(5) 271-298.
extensive reference is made to Stegmann for a number of proposed species but no mention is made of Stegmann's work in the section on michahellis and atlantis.
So Dubois and Yésou ignore (Stegmann) or misquote (Dwight ) both of the seminal articles on atlantis from the first systematic studies of gulls.
Notes on atlantis by Stegmann:
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