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NUMBER 89 25
TABLE 10.—Dimensions (mm) of the main bones of the extinct Fulica newtonii from Mauritius (MNHN) and Reunion.
(a = maximum length in median plane, b=width between sterno-coracoidal processes, c=width between ventral labial
prominences, d=measured with cnemial crests, e=measured without cnemial crests; «=number of specimens.)
Measurement
Sternum (Reunion)
length (a)
width (b)
width (c)
keel depth
Coracoid (Reunion)
internal length
proximal width
proximal depth
midshaft width
midshaft depth
Humerus (Mauritius)
total length
proximal width
proximal depth
distal width
distal depth
midshaft width
midshaft depth
Ulna (Reunion)
distal width
external condyle depth
midshaft width
midshaft depth
Carpometacarpus (Reunion)
total length
proximal width
proximal depth
distal width
distal depth
Mean (ri)
66.7(1)
36.6(1)
27.7(1)
20.7(1)
39.4(1)
10.60(2)
6.70 (2)
5.1(1)
3.8(1)
85.40
17.15(2)
9.6(1)
12.15(2)
7.10(2)
5.50(2)
4.70 (2)
7.2(1)
7.3(1)
4.6(1)
5.1(1)
49.1 (1)
4.6(1)
9.3(1)
3.5(1)
4.8(1)
Range
10.4-10.8
6.5-6.9
83.5-87.3
16.7-17.6
11.7-12.6
6.9-7.3
5.3-5.7
4.5-4.9
identical to that from Mauritius illustrated by Newton and Gadow
(1893, pl. 35: figs. 5-7). It presents a ventral manubrial
spine (spina externa) that is wide, with two small lateral points
separated by a shallow notch. This characteristic cannot be
considered as different from Fulica, however, for in numerous
living species of that genus the ventral manubrial spine is very
variable among individuals. Some individuals have a narrow,
short point prolonged by a median ventral ridge, others have a
short, wide point, and others have two points separated by a
notch, as in F. newtonii. We have observed that the shape of
the ventral manubrial spine is very variable in F. cristata Gmelin
(7 individuals), F. americana Gmelin (20), F. caribaea
Ridgway (3), and F. leucoptera Vieillot (7) from the USNM. In
F. ardesiaca Tschudi (1) and F. rufifrons Philippi and Landbeck
(3), the ventral manubrial spine is wide and short. Three
of seven individuals of F. cristata and two of seven individuals
of F. leucoptera have two points separated by a notch, rather
than a single point.
In Fulica newtonii the anterior carinal margin is more posteriorly
displaced than in F. cristata, but the carina is still well
developed. The shape of this carina is very different from that
of the flightless species Tribonyx mortierii Du Bus, in which
the carina is low and the anterior carinal margin is wide and is
formed by two ridges separated by a median groove. It is still
more different from that of Aphanapteryx bonasia, in which the
Measurement
width metacarpale majus
depth metacarpale majus
Tibiotarsus (Mauritius+Reunion)
total length (d)
total length (e)
proximal width
proximal depth
distal width
distal depth
midshaft width
midshaft depth
Tarsometatarsus (Mauritius+Reunion)
total length
proximal width
proximal depth
distal width
distal depth
midshaft width
midshaft depth
Phalanx 1 digit II (Reunion)
total length
proximal width
Phalanx 1 digit III (Mauritius+
Reunion)
total length
proximal width
Phalanx 2 digit III (Reunion)
total length
proximal width
Mean (n)
3.9(1)
3.2(1)
129.24(5)
122.54(5)
12.56(5)
18.60(5)
12.06(9)
11.67(3)
6.75 (8)
5.14(8)
84.15(6)
13.53 (7)
12.35(2)
13.95(6)
10.80(6)
6.51 (7)
5.09 (7)
37.25 (2)
5.27 (3)
34.30 (2)
7.20 (2)
27.3(1)
6.5(1)
Range
126.8-131.3
120.2-124.6
12.1-13.0
17.7-19.4
11.2-12.8
11.5-11.8
6.2-7.0
4.6-5.7
76.7-89.3
-12.5-14.2
11.4-13.3
12.4-14.8
9.7-11.7
6.0-6.8
4.7-5.3
36.2-38.3
5.1-5.5
34.3-34.3
-7-7.4
anterior carinal margin is very wide, with two ridges separated
by a wide groove, and the carina itself is strongly displaced
posteriorly and is very low (Newton and Gadow, 1893, pl. 35:
figs. 14-16). In conclusion, the characteristics of the sternum
indicate only a slight reduction in flying ability.
Milne-Edwards (1867, 1867-1871) wrote that the shape of
the posterior iliac crests of the pelvis of F. newtonii was more
similar to that of F. atra Linnaeus than to that of F cristata.
Although the two pelves from Reunion are not complete
enough to see if this characteristic is constant in F. newtonii,
we think that by the marked widening of the pelvis at the level
of the acetabula and by the strong projection of the antitrochanters
externally, F. newtonii is more similar to F. cristata
than to F. atra (see Milne-Edwards, 1867-1871, pl. 99: figs.
1-5, pl. 107: figs. \^).
In Fulica newtonii the bones of the scapular girdle and the
wing (coracoid, humerus, carpometacarpus) are the same size
as in a large male of F. cristata, the tibiotarsus and the phalanx
of pedal digit II are slightly larger, and the femur and the tarsometatarsus
are much larger (Figure 10). Compared to F. cristata,
F. newtonii was a poorer flier as indicated by the reduction
of the coracoid and wing bones. For comparison we
present the curves of Tribonyx mortierii, the flightless Tasmanian
Native-Hen, and of Aphanapteryx bonasia, the extinct,
flightless Mauritius Red Rail. In these two species, the cora-