CONSERVATION OF ARABIAN GAZELLES - Nwrc.gov.sa

(2) FEMALES
Variable gazella cora erlangeri bilkis Thumamah
n=8 n=2 n=3 n=3 n=4
Hom length, straight 97.1 104.0 125.0 144.3 117.8
s.d. 19.05 · 17.35 7.64 9. 18
Greatest width across bases of horn 52.0 51.5 50.3 56.3 50.8
s.d. 1.60 · 1.53 1.53 1.7 1
Width of nasal bones (anterior) 20.9 19.0 17.3 20.7 16.3
s.d. 2.47 · 0.58 1.15 0.96
Width of nasal bones (posterior) 23.4 21.5 19.0 22.7 20.5
s.d. 2.33 · 1.73 0.58 0.58
Groat.st length of nasal bones 46.5 46.5 44.3 48.0 47.0
s.d. 3.96 · 8.50 2.65 5.35
Oroatest skull length 18 1.0 172.0 168.7 188.7 178.5
s.d. 4.41 · 10.02 2.52 5.57
GIut.st skull breadth (biorbital) 82.7 no 75.7 84.7 78.8
•. d. 3.96 · 2.52 0.58 2.63
Preorbital skull length 93. 1 90.0 84.7 99.3 92.5
s.d. 3.56 · 7.64 1.15 3.32
Palate width (outside moJars) 52.0 47.0 44.7 51.7 47.5
s.d. 7.17 · 3.21 1.53 1.73
Braincase width 57.5 54.5 55.3 61.0 52.3
s.d. 1.85 · 2.52 2.65 1.50
Braincase length (nasion to ini on) 100.9 92.0 93.3 103.3 96.0
s.d. 3.00 · 4.16 1.15 2.94
In the skulls from the Thumamah breeding stock, the horns of the males are on average
longer than in any other sample of the C. gaze/la group, and more nearly parallel than any but C.
billcis. The horns of females are shorter than in C. bilkis but longer than in C. gazella except for
erlangeri.
2.2).
The distance across the horn bases is broad in C. g. gazella, C. g. cora and C. bilkis (Table
C. dorcas isabella has bowed horns remarkably similar to those of C. g. cora, but longer in
the female. The near identity in horn shape recalls the great external similarity in general (Figure
2.1). In contrast, the horns of C. saudiya are very long and straight in both sexes, with very little
inturning at the tips; they are not very divergent, resembling in this respect the horns of most
subspecies of C. bennelti (Table 2.4), but are narrower across the bases.
The horns are closely ringed in the male, with mare than 20 rings, in C. subgutturosa and C.
saudiya;in the latter the rings are more prominent than in most Arabian gazelles. The rings are much
fewer in number, 12-15, in C. g. muscatensis, C. bilkis and C. arabica, with about 15-20 in the other
forms.
Hom shapes in Arabian gazelles are well illustrated in Morrison-Scott (1939, Plate VI); the
specimens figured could hardly have been better selected to illustrate the manner in which the range
of variation within a taxon, considerable though it may be, does not obliterate the differences
between taxa. In this plate are figured three male and one female C. saudiya (Figures 1-3 and 10,
respectively); one adult and one subadult male C. s. marica (Figures 14 and 15 respec tively); seven
male and one female C. g. cora (Figures 4-9 and 13, and II respectively, all captioned "C. arabica");
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