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NUMBER 89 13
total length
proximal width
phalanx 1 digit III
total length
proximal width
phalanx 2 digit III
total length
proximal width
phalanx 1 digit IV
total length
proximal width
mean {n)
29.97 (3)
7.40 (3)
29.7(1)
8.2(1)
25.3(1)
5.9(1)
20.8(1)
7.4(1)
23; phalanx 1 of the major digit of wing, 1993-26. Additional
Specimen: r. d. radius, 1993-54.
Grotte de l'Autel: Cranium, 330525; sternum, anterior part
and fragment, 330523; 1. coracoid, 330519; 1. scapula, 330524;
r. humerus, 330517; 1. p. ulna, 330518; 2 r. carpometacarpi,
330520, 330522; 1. femur, 330526; r. tarsometatarsus, 330521.
Grotte "au sable": Fragment of furcula, 330735; sacrum, r.
lateral part of pelvis, 1. lateral part of pelvis from same bone,
330730-330732; d. radius, 330733; phalanx 1 of major digit of
wing, 330736; phalanx 2 of major digit of wing, 330734.
Marais de l'Ermitage: Sacrum, 1914; fragment of pelvis
(without number); 2 1. anterior scapulae, 1825, 1889; 2 1. coracoids,
1822, 1888; r. s. humerus, 1821; r. d. ulna, 1892; r. d.
carpometacarpus, 1891; 1. p. carpometacarpus, 1823; 1. s. carpometacarpus,
1890; r. d. tibiotarsus, 1824; r. s. j. tibiotarsus,
1820; 1. d. j. tibiotarsus, 1915; r. d.j. tarsometatarsus, 1893.
REMARKS.—The new genus and species Mascarenachen
kervazoi was created by Cowles (1994) for an extinct sheldgoose
from Reunion. Comparison of a larger quantity of material
from the Grotte de l'Autel and Marais de l'Ermitage, in addition
to that from the Grotte des Premiers Francais, shows that
the Reunion form is very close to the living Alopochen aegyptiacus
(Linnaeus), the Egyptian Goose, which lives in many
parts of Africa. Extinct species of Alopochen also are known
from Madagascar and Mauritius.
Cowles (1994) gave two sets of characteristics in the diagnosis
of the genus Mascarenachen. First, the bill is shorter and is
dorsoventrally deeper at the level of the cranial junction than in
other Tadorninae, and the rostral tip forms a true semicircle,
whereas in the other Tadorninae it is more pointed and forms a
semiellipse (Figure Ig). Second, the sternal carina has an almost
straight, not concave, anterior margin and a pronounced
ventral manubrial spine.
Dubois described the geese of Reunion as being "wild geese,
slightly smaller than European geese. They have the same
feathering, but with the bill and the feet red. They are very
good [to eat]" (Barre and Barau, 1982:30, our translation). This
description applies well to a goose related to A. aegyptiacus,
TABLE 4.—Continued.
T. solitarius
range
29.5-30.8
7.3-7.5
-
-
-
-
-
T. aethiopicus
range («)
24.7-30.8(12)
4.9-6.4(12)
24.3-31.2(12)
5.5-5.8(12)
21.9-26.4(12)
4.2-5.4(12)
19.0-24.1 (12)
5.0-6.5(12)
T. spinicollis
range («)
25.1-25.6(2)
5.6-5.9 (2)
25.6-27.2 (2)
6.4-6.6 (2)
20.1-22.0(2)
4.9-5.1 (2)
18.0-19.8(2)
5.7-6.2 (2)
TABLE 5.—Tarsometatarsus distal width and shaft indices in the extinct
Reunion Ibis Threskiornis solitarius and in modern T. aethiopicus and T. spinicollis.
(Distal-width index=distal width x 100/total length; shaft index=width
midshaft x 100/ depth midshaft; «=number of specimens.)
Species
T. solitarius
T. aethiopicus
T spinicollis
Distal width index Shaft index
mean (w) range mean (w) range
19.92 (4) 19.81-20.04 141.33(5) 129-151
14.65(11) 13.70-15.94 125.45(11) 119-137
17.18(2) 15.82-18.54 127.00(2) 118-136
which has a pink bill and bright pink legs and feet (Brown et
al., 1982).
COMPARISON WITH LIVING FORMS.—After examining 11
specimens of A. aegyptiacus in the USNM and MNHN collections,
we found the cranium and all the elements of the
post-cranial skeleton of Mascarenachen to be morphologically
very similar to those in the genus Alopochen, although differing
from those in all the other genera of Tadorninae. The premaxilla
of the Reunion sheldgoose differs from all specimens
of A. aegyptiacus, however, by its shorter length (Table 6) and
by the semicircular shape of the tip. The rostrum is longer and
anteriorly sharper in A. aegyptiacus. In the Reunion sheldgoose,
the part of the nasal above the nostrils bulges; the nostrils
are not narrow and elongated, as in A. aegyptiacus, but are
more rounded. The dorsal outline of the premaxilla is almost
straight, whereas in A. aegyptiacus it is clearly upturned at the
tip. The premaxilla also is much deeper than in A. aegyptiacus.
The anterior carinal margin of the sternum is almost straight
in the specimen described by Cowles (MNHN LAC-1933-22),
but it is strongly concave in specimen UCB FSL-330523 (Figure
In), which also possesses a ventral manubrial spine that is
narrow but very projecting. The shapes of the anterior carinal
margin and of the ventral manubrial spine are highly variable
in A. aegyptiacus; some individuals have a straight anterior
margin, others a slightly incurved one, and still others a deeply
incurved one. Likewise, some individuals have a very projecting
ventral manubrial spine, others a very short one, and others
no ventral manubrial spine at all.