therya-5_2

Pacheco, Rengifo and Vivas
Phyllotis pearsoni was trapped in the same Puna habitat with Akodon mollis, Akodon
sp., Auliscomys pictus, Calomys sorellus, and Phyllotis andium; and was captured with
Victor, Museum special and Sherman traps with standard bait consisting of oats, peanut
butter, vanilla, honey, raisins, and seeds.
Figure 6. Comparisons
of skulls between
Phyllotis pearsoni nov.
sp. on the left (MUSM
17431) and P. andium
on the right (MUSM
23242). A) dorsal view
of cranium, B) ventral
view of cranium. ir:
interorbital region, mlf:
middle lacerate foramen,
mpf: mesopterygoid
fossa, nas: nasals,
ps: presphenoid, za:
zygomatic arch, zn:
zygomatic notch, zs:
zygomatic spine.
Phyllotis pearsoni showed a greater reproductive activity in the wet season (December
to May) where 84% of the males with reproductive data had morphological evidence of
reproductive activity assessed by the presence of scrotal testes, and 61% of females with
reproductive data showed some reproductive activity (i.e., perforated vagina, mammary
glands developed or lactating). These percentages of reproductive activity decreased to
67% in males and 22% in females during the dry season (June to October).
The fecal content analysis of one individual, evaluated in 10 randomly selected fields,
where the percentage was interpreted as a measure of volume (Solari 1997), revealed a high
abundance of fruits (70%), including fruit remains (54.7%) and seeds (15.3%), followed
by other plant remains (18%), and a small percentage of insect larvae remains (3.3%;
Fig. 10), 8.7% were undetermined material. Seeds were identified as a morphospecies
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