Revista Chilena de Historia Natural 85 (1): 13-27, 2012
RESEARCH ARTICLE
Natural history of a rare rodent of the Argentinean desert, Salinomys
delicates (Cricetidae: Sigmodontinae)
The delicate mouse (Salinomys delicatus) is a small rodent
endemic of Argentina. It has been considered vulnerable to extinction because of its restricted and patchy distribution,
small population size and specialization on salty habitats. Besides its morphological and physiological adaptations to
survive in arid and salty habitats, there is still little information about the natural history of the delicate mouse. The
objectives of our study are to study the natural history of S. delicatus, report new localities of occurrence,
characterize its habitat use, diet and accompanying assemblages and describe its reproductive biology and morphology.
We report two new localities of occurrences in gallery woodlands and salt flats in the northeast of Mendoza province
(Argentina), these being the fi rst records for this province. Like other South American rodents, S. delicatus has
an omnivorous diet consisting in similar proportion of seeds, arthropods and halophytic plants. The assemblages are
composed by no more than three small mammal species, varying according to the locality. Sex ratio and the pattern of
sexual dimorphism shows a strong bias towards females (H:M = 3.6:1.1 and H:M = 1.151 respectively). External and cranial
morphology exhibits a clear intra- and interpopulation variability. When considering in the analysis adults and juvenile, two
of six external measurements (head and body length and total length) and seven of twenty-two cranial measurements were
significantly higher in females than in males. When considering only adults, four external measures (total length, head and
body length, tail length and weight) and six cranial measurements were significantly higher in females than in males. This
integrative analysis highlights the relevance of conducting further and more detailed studies on the natural history of
S. delicatus and allows us to reassert the conservation importance of this species.
Key words:
arid lands,
conservation, delicate mouse, life history, salt flats
