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Cor.
Hum.
Cpm.
Fern.
Tbt.
Tmt.
Phal. 1 post,
digit II *
100 50 50 100
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SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
• Fulica atra, standard
• Aphanapteryx bonasia
)|c Tribonyx mortierii
+ Fulica newtonii, min. and max.
o Fulica cristata
150 200
FIGURE 10.—Ratio-diagram of long bones of Fulica newtonii compared to those of F cristata (male, USNM
430843), Tribonyx mortierii (UCB, Lyon 1975-1), and Aphanapteryx bonasia. The standard is Fulica atra (UCB,
Lyon 147-2). For Fulica newtonii the minimum and maximum dimensions of the fossil material from Mauritius
and Reunion are indicated and include measurements given by Newton and Gadow (1893). For the extinct Aphanapteryx
bonasia, the dimensions are from the fossil material at MNHN (MAD 6501, 6502, 6561, 6565, 6566,
6579, 6580, 6818, 6937, 6967) and from Newton and Gadow (1893). Coracoid measurement is of internal
length; for other bones, measurement is of total length. When measurements are not known, successive points are
united by dashed lines. (Cor.=coracoid, Cpm.=carpometacarpus, Fem.=femur, Hum.=humerus, Phal.= phalanges,
post.=posterior, Tbt.=tibiotarsus, Tmt.=tarsometatarsus.)
coids are the same size as in F. newtonii, and the proportions of
the leg bones are very similar to those of F. newtonii, but the
reduction of the wing is much more advanced. The pedal phalanges
are much shorter in T. mortierii. So it can be concluded
that F. newtonii had some reduction in flying ability but was
still able to fly, which explains how the same species could be
present on both Mauritius and Reunion.
Several early authors have mentioned the presence of
"moorhens" on Reunion, but the most detailed description was
given by Dubois: "Moorhens, which are as big as hens. They
are completely black and have a big white crest on the head"
(Barre and Barau, 1982:30, our translation). On these grounds,
Milne-Edwards (1867-1871) said that F. newtonii must have
been very different from F. cristata, the forehead shield of
which is dark red; actually, the forehead shield in F. cristata is
white, sometimes tinged with pink, and is topped by two more
or less developed red tubercles in the adult (Langrand, 1990).
Keith (in Urban et al., 1986:129) wrote that the Red-knobbed
Coot is "not easy to tell from the Eurasian Coot, F. atra. At
close range red knobs at top of shield distinguish it, but during
non-breeding season they are small and very hard to see."
In conclusion we think that F. newtonii was probably derived
from F. cristata, which lives mainly in southern and East Africa
and on Madagascar. It is not possible, however, to exclude
the possibility that it could be derived from F. atra, for this
species is widely distributed in the Palearctic region as well as
in India, Indonesia, Australia, Tasmania, and New Zealand
(Cramp and Simmons, 1979).
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