L. Forró szerk.: Miscellanea Zoologica Hungarica 7. 1992 (Budapest, 1992)
Borroto Páez, R., Camacho Pérez, A.; Ramos García, I.: Variation in three populations of Capromys pilorides (Rodentia: Capromyidae), and the description of a new subspecies from the south of the Isle of Youth (Cuba)
When viewed from the side, the top of the skull at the frontal bones tends to be concave in the southern form and in C. p. relictus, although more frequently so in the former. This outline tends to the flat in almost all individuals of C. p. pilorides. However, the outline of the neurocranium, i.e. in the parietal zone, tends to the flat in over half of the southern form, while in the other two subspecies almost all crania showed an inclination towards the basal part. In the southern form the posterior sutures of the nasal bones are behind the premaxillaries in nearly twothird of the individuals and are at the same level as these in the rest. However, in relictus these frequencies are 16.7% and 77.8%, while 5.5% do not attain the level of the premaxillaries. The latter character was nevertheless used by Allen' (1911) in his description of relictus, since it is the only subspecies, of those that have been studied, where it appears. The incisor foramen is more frequently placed between PM and M 1 in both Isle of Youth populations, although there are more individuals with this foramen at M 1 level within the southern population. In C. p. pilorides this position is always at the level of PM. The jugal processes extend further than the posterior alveole of M 3 over two-third of the southern form, while in less than half of the individuals of C. p. relictus and half of C. p. pilorides this level is not even reached. This same structure, when analyzed vertically and relative to the surface of the molars, is commonly below the level of the surface of M 3 in all the forms here analyzed although the other two states of this character are found more frequently in the southern form than in the subspecies relictus and pilorides. The southern form is the largest in a set of quantitative characters that separate it from C. p. relictus, such as zygomatic width, height of rostrum, length of the frontal bone, horizontal diameter of postorbital fossa, the distance between the bulla osseae and the M 3 alveole, posterior width of the nasal bone, interorbital width, horizontal and vertical diameters of foramen magnum and the height of the condylar process in the mandible (Table 3). Table 3. Means±S.D. of cranial measurements of three populations of Capromys pilorides Character C. p. pilorides 11=14 C.p. relictus n = 18 southern form n=19 F Lengths COND 87.34±5.39 89.20±4.72 90.79±5.01 1.91 NS PLT 25.71 ±1.94 a 23.56 ±1.64 b 25.17±1.38 a 7.80 ** PAL 44.44±3.36 43.81 ±2.42 45.66 ±2.60 2.14 NS BPN 33.30 ±2.20 34.70±3.16 34.66±2.39 1.39 NS D 25.49 ±1.86 26.31 ±1.78 26.69 ±1.54 2.01 NS R 36.32±2.64 32.39 ±2.39 37.66 ±2.05 1.84 NS MTR 21.68±1.11 21.34±1.21 21.52±1.50 0.26 NS B 16.41±1.02 15.97±0.73 16.53±0.98 1.95 NS N 28.14±2.04 28.19±2.19 28.50±2.82 0.12 NS F 29.76 ±1.94 c 32.44±2.05 b 34.50 ±1.72 a 24.62 *** PF 36.08 ±2.10 35.60 ±2.59 37.09±2.65 1.74 NS HDP 22.16±1.68 ab 21.78±2.08 b 23.28±1.64 a 3.38 HDO 14.12±0.93 14.08±0.69 14.30±1.00 0.33 NS IF 10.14±0.99 b 10.98±1.65 ab 11.20±1.37 a 2.58 * BA 15.47±1.45 b 16.19±1.93 b 17.79±2.32 a 6.15 * * Widths Z 48.06±3.61 47.08±3.73 48.33 ±3.08 0.65 NS NC 32.98 ±1.31 33.09±1.75 34.07±2.47 1.66 NS
