The Cardinal Honey-eater at Palau is distinguished from other subspecies of M. cardinalis in Micronesia by its deeper red coloring. In size, it closely resembles the bird at Yap and in the Marianas.
Evolutionary history of Myzomela cardinalis in Micronesia.—The genus Myzomela is found in Australia, northward to Timor, Tenimber, Moluccas, Celebes, Melanesia, Polynesia and Micronesia. The range of the species M. cardinalis includes the islands from the eastern Solomons, New Hebrides, and Loyalty Islands east to central Polynesia and north to Micronesia. It appears likely that M. cardinalis was derived, probably along with M. nigrita, M. lafargei and others, from an ancestral stock in the Melanesian area. Within the species M. cardinalis there is one group of subspecies which exhibits a marked degree of sexual dimorphism, with the males having a much greater amount of red coloration than the females. These subspecies occur in the southern part of the range of the species (Loyalty, Santa Cruz, New Hebrides, and Samoa islands). A second group of subspecies exhibit a lesser amount of sexual dimorphism, the females possessing more of the red coloration and resembling the males more closely. This second group includes subspecies which occur in the more northern part of the range of the species (Solomons, Micronesia, and Rotuma islands). The males of the various subspecies of M. cardinalis vary one from another considerably less than do the females.
Fig. 16. Geographic distribution of Myzomela cardinalis and routes of its dispersal. (1) Probable center of dispersal of Myzomela; (2) ranges of M. c. sanfordi and M. c. pulcherrima in the Solomon Islands; (3) M. c. rubratra; (4) M. c. dichromata; (5) M. c. major; (6) M. c. kurodai; (7) M. c. kobayashii; (8) M. c. saffordi; (9) M. c. chermesina; (10) range of M. cardinalis in the Santa Cruz, New Hebrides, Banks and Loyalty islands; (11) M. c. nigriventris.
[Figure 16] shows the probable routes of colonization used by M. cardinalis to attain its present distribution in the Pacific islands. The subspecies in the eastern Solomon Islands (M. c. pulcherrima Ramsey and M. c. sanfordi Mayr) may be representative of the first colonization by the supposed ancestral stock. From a focal point in this area, M. cardinalis has dispersed by what may be considered as two routes. One route evidently was to the south as far as the Loyalty Islands with a side branch extending to the Samoan Islands where M. c. nigriventris Peale occurs. The second route extended north to the islands of Micronesia. The Caroline Islands were seemingly inhabited initially, with invasions of the Palaus made via Yap, and of the Marianas via Kusaie or Ponapé (as indicated by the comparison of specimens). Mayr (in conversation) has pointed out the close relationship between the subspecies in Micronesia and M. c. chermesina Gray of Rotuma Island. This subspecies at Rotuma, which is located between Santa Cruz and Samoa, resembles closely M. c. dichromata of Ponapé, especially in the case of the female. It is evident that the honey-eater arrived at Rotuma from Micronesia, rather than from the Solomon and Santa Cruz area to the west.
Zosterops conspicillata conspicillata (Kittlitz)
Bridled White-eye
Dicaeum conspicillatum Kittlitz, Kupfertaf. Naturgesch. Vögel, 2, 1833, p. 15, pl. 19, fig. 1. (Type locality, Guaham.)
Dicaeum conspicillatum Kittlitz, Mém. Acad. Imp. Sci. St. Pétersbourg, 2, 1835, p. 3, pl. 4 (Guaham); idem, Obser. Zool., in Lutké, Voy. "Le Séniavine," 3, 1836, p. 305 (Guaham).