Scaeophaethon rubricauda rothschildi Mathews, Birds Australia, 4, 1915, p. 303. (Type locality, Laysan and Niihau.)
Phaeton rubricaudus Finsch, Journ. f. Ornith., 1880, p. 296 (Carolines); idem, Ibis, 1881, p. 115 (Ponapé).
Phaeton rubricauda Finsch, Proc. Zool. Soc. London, 1880, p. 577 (Ruk); Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden, no. 6, 1890-1891 (1891), p. 73 (Ruk, Ponapé, Marshalls).
Phaeton rubricauda Ogilvie-Grant, Cat. Birds British Mus., 26, 1898, p. 451 (Caroline Islands); Hartert, Novit. Zool., 7, 1900, p. 11 (Ruk); Hand-list Japanese Birds, rev., 1932, p. 187 (Pagan, Truk, Ponapé, Marshalls).
Scaeophaethon rubricauda Kuroda, in Momiyama, Birds Micronesia, 1922, p. 34 (Mariannes, Ruk, Ponapé, Marshalls).
Phaethon rubricauda rothschildi Yamashina, Tori, 7, 1932, p. 406 (Pagan); idem, Tori, 10, 1940, p. 676 (Maug).
Phaethon rubricaudus rothschildi Hand-list Japanese Birds, 3d ed., 1942, p. 209 (Maug, Pagan, Truk, Ponapé, Marshalls).
Geographic range.—Bonin and Hawaiian islands south to Micronesia. In Micronesia: Mariana Islands—Maug, Pagan; Caroline Islands—Truk, Ponapé; Marshall Islands—exact locality unknown.
Characters.—Adult: Long-tailed sea bird white with pinkish tint except for black lores and eye streak; black shafts on feathers of secondaries, flanks, and tail coverts; black bases on feathers of head; central tail feathers elongate with black shafts and bright red webs; bill orange-red with black nasal streak; tarsus and foot bluish-yellow, distal part blackish. Immature: Resembles adult but barred with black above; bill blackish.
Measurements.—Yamashina (1940:676) lists the measurements for seven adult birds from Maug in the northern Marianas as wing 304-319 and exposed culmen 55-62.