_Rallus monasa_ Kittlitz, Denks. Riese russ. Amer. Micron. und
Kamchat., 2, 1858, p. 30. (Type locality, Kushai.)
_Rallus tabuensis?_ Kittlitz, Obser. Zool., in Lutké, Voy. "Le
Séniavine," 3, 1836, p. 286 (Ualan).
_Ortygometra tabuensis_ Finsch, Journ. f. Ornith., 1880, pp. 297,
307 (Kuschai); _idem_, Ibis, 1881, pp. 106, 109 (Kushai);
Wiglesworth, Abhandl. und Ber. Zool. Mus. Dresden, no. 6,
1890-1891 (1891), p. 60 (Ualan).
_Kittlitzia monasa_ Hartlaub, Abhandl. nat. Ver. Bremen, 12, 1892,
p. 391 (Kuschai); Finsch, Mitth. Ornith. Ver. Wien, 17, 1893, p. 1
(Kuschai).
_Aphanolimnas monasa_ Sharpe, Bull. British Ornith. Club, 1892, p.
20 (Kuschai); Finsch, Deut. Ver. zum Schulze der Vogelwelt, 18,
1893, p. 457, pl. 4 (Ualan); Wiglesworth, Ibis, 1893, p. 214
(Kushai); Sharpe, Cat. Birds British Museum, 23, 1894, p. 115
(Kushai); Matschie, Journ. f. Ornith., 1901, pp. 110, 113 (Ualan);
Mathews, Syst. Avium Australasianarum, 1, 1927, p. 93 (Caroline
Islands); Hand-list Japanese Birds, rev., 1932, p. 197 (Kusaie);
Peters, Check-list Birds World, 2, 1934, p. 189 (Kusaie);
Hand-list Japanese Birds, 3d ed., 1942, p. 221 (Kusaie); Mayr,
Birds Southwest Pacific, 1945, p. 288 (Kusaie); _idem_, Audubon
Mag., 47, 1945, p. 280 (Kusaie).
_Porzana tabuensis_ Sharpe, Cat. Birds British Mus., 23, 1894, p.
111 (Kushai).
_Pennula monasa_ Dubois, Syn. Avium, 2, 1904, p. 969 (Kuschai).
_Porzana tabuensis tabuensis_ Kuroda, in Momiyama, Birds
Micronesia, 1922, p. 42 (Kusaie).
_Geographic range._--Micronesia: Caroline Islands--Kusaie (probably
extinct).
_Characters._--Sharpe (1894:115) gives the following description:
"Adult. Black with a bluish-grey reflexion; quills and tail
somewhat browner; inner wing-coverts brownish with white spotting,
outer edge of first primary dull brownish, chin and middle of the
throat somewhat paler; bill blackish (Hartlaub.)."
_Remarks._--Two specimens of this rail are known. The two were taken by
Kittlitz on his visit to Kusaie in December and January of 1827-'28.
Coultas made a search for the bird in 1931 and failed to obtain it; he
suggested that the high population of introduced rodents may have been a
factor contributing to its extinction. The bird is considered to be
extinct by the authors of the Hand-list of Japanese Birds (Hachisuka _et
al._, 1942:221).
The two known specimens are in Leningrad, and Mayr sent examples of
_Porzana tabuensis_ there for comparison. The following is a translation
of the letter received by Mayr from Boris Stegmann dated at Leningrad,
December 7, 1937.
"I have compared the two specimens of _Porzana tabuensis_ with our
specimens of _Aphanolimnas monasa_. The difference is in my opinion of
generic value. _Aphanolimnas_ is distinctly larger and more robust. The
bill is not only absolutely but also relatively longer. Its length
(measured from the forehead) reaches to the end of the second phalanx of
the middle toe while it not nearly reaches it in _tabuensis_. The
proportions of feet and toes are the same in both, but the feet are
distinctly heavier in _Aphanolimnas_. The wings are relatively shorter
in _Aphanolimnas_ and the wing feathers are very soft. The wing is also
much more rounded, the first primary is about 21 mm. shorter than the
wing tip. The tail consists of very soft loose feathers which resemble
only distantly true tail feathers. It is therefore questionable whether
this bird was at all able to fly.
"The coloration is in general dull black, brownish black on head and
wings, chin and upper throat are dark slate colored lighter in the
middle. The under wing and tail-coverts are marked with scattered white
spots (querflecken). The first primary has an irregular whitish brown
margin on the outer web. The bill is dark and the feet yellowish."
Possibly this rail represents an ancient colonization of Kusaie from an
ancestral stock of _Porzana_ in Polynesia. Mayr (1941b:203) is also of
this opinion, and if this is true there is no close relationship between
_Aphanolimnas_ and the rails at Guam and Wake, _Rallus owstoni_ and _R.
wakensis_, which are probably colonizers from the Philippines or the
Papuan area. Mayr (1943:46) remarks further that the Hawaiian
flightless rail (_Peuula_) is of doubtful taxonomic position, but may be
related to the "_Aphanolimnas_-_Porzanoidea_-_Nesophylax_ stock,"
although there is no evidence that _Pennula_ is not related to _Rallus_.
Supposed colonization routes are shown in figure 9.
=Poliolimnas cinereus micronesiae= Hachisuka