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24 SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
TABLE 9.—Dimensions (mm) of the bones of the Reunion Rail, Dryolimnas
augusti, new species, compared with recent Dryolimnas cuvieri cuvieri from
Madagascar (BMNH 1897.5.10.47), and D. cuvieri aldabranus from Aldabra
(BMNH s/1989.38.5, BMNH s/1993.6.2). («=number of specimens.)
Measurement
Coracoid
midshaft width
midshaft depth
Humerus
total length
proximal width
head width
midshaft width
midshaft depth
Ulna
total length
proximal width
proximal depth
midshaft width
midshaft depth
Femur
total length
distal width
distal depth
midshaft width
midshaft depth
Tibiotarsus
proximal width
proximal depth
distal width
distal depth
Tarsometatarsus
total length
proximal width
proximal depth
distal width
distal depth
midshaft width
midshaft depth
Dryolimnas
augusti, n. sp. (ri)
3.2(1)
2.3(1)
-48(1)
10.0(1)
3.0(1)
3.3 (2)
3.3 (2)
-40(1)
4.8(1)
5.4(1)
2.7(1)
3.0(1)
-61(1)
10.1-11.3(3)
9.0-9.1(2)
4.5^.9 (4)
4.4-5.0 (4)
9.7(1)
12.1(1)
-7.8(1)
-8.0(1)
53.0-53.1 (2)
8.7-8.8 (2)
9.2 (2)
9.5(1)
7.2(1)
4.3-4.4 (2)
3.8-3.9 (2)
Dryolimnas cuvieri
cuvieri (n=\)
3.1
1.9
47.9
9.7
2.8
3.1
2.9
41.2
4.7
5.1
2.3
2.6
50.5
8.3
7.3
3.6
3.6
7.4
10.1
6.7
7.0
47.6
7.2
7.1
7.2
5.9
3.0
2.6
aldabranus (M=2)
2.1,2.2
1.5,1.5
37.7,39.0
8.1,8.7
2.2,2.2
2.2,2.3
2.1,2.2
31.0,32.5
3.8,4.0
3.8,4.0
1.6,2.1
2.1,2.3
42.8,44.8
7.1,7.5
6.6,6.6
2.9,3.3
3.1,3.3
6.3, 6.4
8.9, 9.4
5.8,5.9
6.0, 6.5
40.2, 44.2
6.1,6.5
6.3, 6.4
6.6, 6.6
5.3, 5.4
2.7,2.7
2.2,2.3
rower proximal and distal parts. In Aphanapteryx the hypotarsus
projects more posteriorly and the external calcaneal ridge is
situated closer to the external side; in the Reunion Rail this
ridge is situated more medially. The Reunion Rail differs from
Erythromachus by the characteristics of the humems (shaft thin
and incurved), femur (more elongated and incurved), and tarsometatarsus
(trochleae less splayed).
In the ratio distal width x 100: total length, the Reunion Rail
occupies an intermediate position between Dryolimnas cuvieri,
which has less splayed trochleae, and more terrestrial rails,
such as Erythromachus, Aphanapteryx, and Gallirallus, which
have more splayed trochleae. This ratio varies between 14.9
and 16.4 inD. cuvieri, is 17.9 in D. augusti, varies between
19.2 and 21.2 in E. leguati (after the measurements given by
Gunther and Newton, 1879), varies between 20.6 and 20.9 in A.
bonasia (MNHN), and reaches 20.2 and 22.8 in two specimens
of Gallirallus australis (MNHN).
REMARKS.—The Reunion Rail is likely to correspond to a
bird that was mentioned only by Dubois (1674) as Rale des
Bois. It cannot correspond to the Oiseau Bleu, which must have
been larger, being the same size as a solitaire, according to
Dubois, or the size of a large capon, according to Feuilley
(Cheke, 1987). The Reunion Rail was smaller, approximately
the size of a Common Moorhen {Gallinula chloropus (Linnaeus)),
with reduced wings.
A fossil rail from Mauritius was recently identified as Dryolimnas
cuvieri by Cowles (1987).
Genus Fulica Linnaeus
Palaeolimnas Forbes, 1893:544 [type by monotypy, Fulica newtonii Milne-Edwards,
1867].
Paludiphilus Hachisuka, 1953:154 [type by monotypy, Fulica newtonii Milne-
Edwards, 1867].
Fulica newtonii Milne-Edwards, 1867
Newton's Coot
FIGURE \li-m
Fulica newtonii Milne-Edwards, 1867:203, pl. 10.
Fulica newtoni.—Anonymous [=A. Newton], 1868:482.
Palaeolimnas newtoni.—Forbes, 1893.
Paludiphilus newtoni.—Hachisuka, 1953.
MATERIAL.—Grotte des Premiers Francais: Rostrum, anterior
part, 1993-44; sternum, 1993-39; incomplete pelvis, 1993-
38; 2 vertebrae, 1993-46; r. tibiotarsus, 1993-40; r. tibiotarsus,
1993-41; fibula, 1993-43; r. tarsometatarsus, 1993-42; 5 pedal
phalanges, 1993-45.
Grotte de l'Autel: Pedal phalanx 1 of digit III, 330528;
pedal phalanx 2 of digit III, 330531.
Marais de l'Ermitage: Fragments of pelvis, 1819; r. coracoid,
1814; r. p. coracoid, 1922; I. d. ulna, 1815; 1. carpometacarpus,
1921; r. d. tibiotarsus, 1816; 2 tarsometatarsi, r. and 1.,
from same individual?, 1811, 1812; r. tarsometatarsus, 1920; r.
p. tarsometatarsus, 1813; pedal phalanx 1 of digit II, 1817; pedal
phalanx 1 of digit II, 1818; 2 pedal phalanges, 1896, 1923.
REMARKS.—Remains of Fulica newtonii in MNHN from the
Mare aux Songes, Mauritius, were compared with those from
Reunion and were found to be identical, so both populations
must have belonged to a single species. The tarsometatarsi
show a great range of variation (Table 10), which probably relates
to sexual dimorphism, with the males being larger than
the females.
Newton and Gadow (1893:292) wrote: "The sternum of F.
newtoni resembles in several points that of Aphanapteryx,
Erythromachus, and Ocydromus, and differs from Tribonyx,
Fulica proper, and Porphyrio, first in the configuration of the
whole anterior margin of the sternum, especially in the double
or basally divided spina externa, which is moreover broad and
flat, while in the other genera this spine is single and furnished
with a ventral longitudinal sharp ridge; secondly, by the receding
and broad anterior margin of the keel, which, however, is
well developed, although less than in Tribonyx and Fulica atra,
but the tendency towards a reduction of the keel is apparent."
The sternum of Fulica newtonii from Reunion (Figure 13/) is