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28 SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
TABLE 11.—Dimensions (mm) of the humerus of Nesoenas mayeri, modem and fossil, from Mauritius, and N.
duboisi, extinct, from Reunion. The modem skeletons of N. mayeri are from USNM, and the fossil humeri are
from the caves of Montagne du Pouce, Mauritius (MNHN). (a=from external tuberosity to bicipital crest, without
deltoid crest; b=from internal tuberosity to bicipital surface, without deltoid crest; «=number of specimens;
5=standard deviation.)
Measurement
Humems
total length
proximal width (a)
proximal depth (b)
distal width
distal depth
midshaft width
midshaft depth
midshaft widthxlO/total length
Genus Streptopelia Bonaparte
Streptopelia picturata (Temminck, 1813)
Madagascar Turtledove
FIGURE 13«
mean (n)
45.58 (34)
13.63(29)
8.38 (27)
10.54(35)
6.54(31)
4.95 (39)
3.88 (39)
1.09(33)
MATERIAL.—Grotte "au sable": r. p. humems, 330738; 1.
d. ulna, 330739.
REMARKS.—Both remains correspond to the living Streptopelia
picturata (one skeleton in MNHN). They are similar to
fossil remains from the caves of Le Pouce Mountain, Mauritius.
The Madagascar Turtledove lives now in Madagascar and
on other islands of the western Indian Ocean (Glorioso, Anjouan
in the Comoros, Aldabra, Assumption, the Amirantes,
some of the Seychelles, and Diego Garcia; Peters, 1937). Although
assumed to have been introduced to Reunion, Mauritius,
and Rodrigues, its presence as a fossil indicates that it was
living on these three islands before humans arrived, disappeared,
and was then reintroduced (Cheke, 1987).
Dubois spoke of ramiers and turtledoves in Reunion, and according
to Cheke (1982), the name Pigeon ramier is still used
in Mauritius and Reunion to designate S. picturata.
Family PSITTACIDAE
Genus Mascarinus Lesson
Mascarinus mascarinus (Linnaeus, 1771)
Mascarene Parrot
FIGURE 13O-JC
MATERIAL.—Grotte des Premiers Francais: r. d. coracoid,
1993-56.
Grotte de l'Autel (bones probably from one individual): 1.
coracoid, 330545; r. and 1. humeri, 330539, 330540, respectively;
1. ulna, 330541; 1. carpometacarpus, 330544; 1. femur,
330543; 1. tibiotarsus, 330542.
Grotte "au sable": 1. scapula, 330810; 2 1. coracoids,
330741, 330742; r. p. coracoid, 330743; r. s. carpometacarpus,
330740; r. d. tarsometatarsus, 330744.
REMARKS.—We think the few remains of a large parrot are
Nesoenas mayeri
s
1.64
0.54
0.37
0.46
0.18
0.20
0.24
0.05
range
42.5-19.2
12.7-14.4
7.7-9.1
9.3-11.4
6.2-6.9
4.6-5.3
3.4-4.4
1.01-1.20
Nesoenas duboisi
50.4
14.2
-
10.4, 11.1
6.6, 6.6
5.1
4.0
1.01
from Mascarinus mascarinus, a genus and species endemic to
Reunion that became extinct between 1750 and 1800 (Barre
and Barau, 1982). Unfortunately, no skeleton has been preserved
for this species, which is known from two mounted
specimens, one in MNHN (Paris, 1998-1725) and the other in
the Natural History Museum of Vienna (Austria, 50.688). X-radiographs
made it possible to take the measurements of some
bones, which show that the fossil remains are intermediate between
those of the two modem specimens (Table 12).
We have compared the fossil remains from Reunion with the
species Coracopsis nigra (Linnaeus), the Lesser Vasa Parrot,
which lives on Madagascar, the Comoros, and on Praslin in the
Seychelles. Coracopsis nigra was introduced to Reunion very
early, circa 1780 (Cheke, 1987), and is about the same size as
M. mascarinus; in both species the total length is 35 cm (Langrand,
1990; Forshaw, 1973). The lengths of the coracoid, femur,
and tibiotarsus of the Reunion parrot fall within the range
of variation of C. nigra, whereas the humems, ulna, and carpometacarpus
are somewhat smaller (Table 12). The parrot of
Reunion also shows morphological differences compared with
C. nigra. The distal part of the humems is more laterally compressed
in the Reunion form, and the olecranal fossa is narrower,
whereas in Coracopsis nigra, as well as in C. vasa (Shaw),
the distal part of the humems is mediolaterally wider (Figure
11). The ratio distal depth x 100:distal width is 65.6 in the
Reunion parrot, whereas it ranges from 57.3 to 63.0 in six modem
C. nigra and from 57.8 to 59.7 in two modem C. vasa. On
the distal part of the tibiotarsus from Reunion (Figure 13x), on
the anterior face, the internal condyle is narrow, not flattened,
and is proximodistally oriented, whereas in C. nigra it is wide,
flattened, and oriented proximointernally. In five of the six C.
nigra examined, the tendinal groove is situated almost in the
median plane of the bone; in the Reunion form, it is situated almost
on the internal side. On the Reunion tibiotarsus there is a
depression on the anterior face, above the external condyle, but
this depression does not exist in C. nigra. Other differences
probably occur in the proximal part of the tarsometatarsus, but
this is unknown in the Reunion form. At the distal end, on the
posterior face, the accessory trochlea is less anteroposteriorly
developed in the Reunion parrot than in C. nigra.