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20
sometatarsus are proportionally longer. These proportions do
not indicate a reduction in flying ability. They are very different
from those of flightless teals, such as A. aucklandica (Gray)
or the extinct form Anas marecula Olson and Jouventin (1996)
from Amsterdam Island (Martinez, 1987; Olson and Jouventin,
1996). Thus it is possible that A. theodori had normal flying
ability and could fly between Mauritius and Reunion, which
explains how the same species could occur on both islands.
The only mention of small anatids on Reunion is by Dubois:
"River ducks, smaller than European ones, feathered like teals.
They are good [to eat])" (Barre and Barau, 1982:30, our translation).
ANATIDAE, cf. Aythya Boie
cf. Aythya sp.
FIGURE lo.p
MATERIAL.—Marais de l'Ermitage: r. carpometacarpus,
1924; 1. p. carpometacarpus, 1925.
REMARKS.—Two carpometacarpi from the Marais de l'Ermitage
differ from the genus Anas in that the alular metacarpal
does not project very far anteriorly, does not rise very much
proximally, and, on the internal face, the posterior outline of
the carpal trochlea is less rounded. Thus, they look more similar
to the genus Aythya, but the pisiform process is broken,
making the generic attribution uncertain.
In their dimensions (total length 46.8 mm), the carpometacarpi
from Reunion correspond to the Northern Hemisphere
species A. marila (Linnaeus) or A. ferina (Linnaeus). Around
the Indian Ocean the genus Aythya is represented by three species,
A. baeri (Radde) (Southeast Asia and China), A. australis
(Eyton) (Australia), and A. innotata (Salvadori) (Madagascar).
The length of the carpometacarpus is known for one individual
of A. innotata (42.9 mm; Goodmann, pers. comm., 1995). Given
the wide range of variation in this species (Hoyo et al.,
1992), it is possible that the Reunion specimens belong to A.
innotata.
Family FALCONIDAE
Genus Falco Linnaeus
Falco duboisi Cowles, 1994
Reunion Kestrel
FIGURE 13a-e
MATERIAL.—Grotte des Premiers Francais. Holotype: 1.
tarsometatarsus, 1993-28. Paratypes: Mandible, left part and
symphysis, 1993-34; furcula, 1993-32; 1. coracoid, 1993-31; 1.
femur, 1993-29; 1. tibiotarsus, large size, 1993-30; r. tibiotarsus,
small size, 1993-33. Additional Specimen: r. ulna, 1993-
53.
SMITHSONIAN CONTRIBUTIONS TO PALEOBIOLOGY
Grotte de l'Autel: r. coracoid, 330547; 1. coracoid, 330548.
REMARKS.—This species was described by Cowles (1994)
on the material from the Grotte des Premiers Francais. An additional
ulna was found later, and two additional coracoids were
found in the Grotte de l'Autel. The species is characterized by
a size generally comparable to that of Falco tinnunculus Linnaeus
but with more robust leg bones. In the holotypical tarsometatarsus
in particular, the proximal and distal ends are
wider and deeper.
The two tibiotarsi (Figure I3b,c) are very different in size
(57.9 mm compared with 66.8 mm). Cowles indicated that the
smaller one is immature, but we disagree because the external
aspect of the bone is that of an adult. The difference between
the two bones is similar to the range of variation between extremes
in Falco punctatus Temminck from Mauritius (Table
8). This size variation is due to sexual dimorphism, with the
largest individuals being the females, as in other species of
Falco (Jones, 1987).
As a whole, Falco duboisi is much larger than F. araea
(Oberholser) (Seychelles) or F. newtoni (Gurney) (Madagascar
and Aldabra) and is slightly larger than F. punctatus. Jones
(1987:209) indicated that in F. punctatus the wings are short
and rounded at their tip, which is an adaptation for forest-dwelling
raptors and also is found in other insular forms of
the genus Falco, such as F. novaeseelandiae Gmelin, from
New Zealand, and F. araea. The shape of the wings is convergent
with that of the hawks of the genus Accipiter, which also
live in forests.
Compared with Falco tinnunculus, the coracoid (Figure 13/)
and wing bones of F. punctatus are much shorter, the femur
and tibiotarsus are slightly shorter, and the tarsometatarsus is
almost the same size (Figure 8). In F. duboisi the humerus and
carpometacarpus are unknown, but the coracoid and the ulna
are not reduced compared with the femur and the tarsometatarsus.
The coracoid, the femur, and the tarsometatarsus have the
same relative proportions as in F. tinnunculus, whereas in F
punctatus the coracoid is very reduced compared with the leg
bones. Thus, it can be concluded that the wings of F. duboisi
were not as shortened as in F. punctatus.
In the historical accounts, Dubois noted three birds of prey.
The first were the papangues, Circus maillardi Verreaux,
which are still living. "The second ones are named yellow-feet,
with the size and shape of falcons. They do harm to the fowls
of the inhabitants and the game of the island. The third ones are
emerillons, which, although small, do not fail to carry away
chickens and eat them" (Barre and Barau, 1982:31, our translation).
The word emerillon is the French name of Falco columbarius,
the merlin, which is a small form, whereas F. duboisi
was almost the same size as F. tinnunculus, the kestrel. We
think that it is perhaps the term "yellow-feet" that corresponds
to F. duboisi.