|The Mammals of Texas -
Elliot's Short-tailed Shrew
Insectivora : Family Soricidae
: Blarina hylophaga Elliot
short-tailed shrew is nearly identical in appearance to
the southern short-tailed shrew, B. carolinensis; both being tiny, slate-gray to brownish
colored shrews with short tails and no external ears. B.
hylophaga differs in having slightly larger cranial
measurements and a noticeably larger fourth premolar.
Also, B. hylophaga tends to be grayish in
coloration, whereas B. carolinensis is often
tinged with brown. Dental formula and external
measurements as in B. carolinensis.
Distribution in Texas. Known in Texas
only from Aransas, Montague, and Bastrop counties.
Pleistocene fossils of this shrew are known from cave
sites throughout the Hill Country.
Habits. In Aransas County, these
shrews inhabit mottes of live oak trees on sandy soils,
where they excavate their diminutive burrows. In Bastrop
County, they have been collected in pitfall traps placed
in grassy vegetation with an overstory of loblolly pine.
Specimens from Montague County were obtained in a pitfall
trap set in grassy vegetation several meters from some
post oak trees. As with B. carolinensis, they may
burrow extensively under leaf litter, logs, and deeply
into the soil, but ground cover is not required. At
Aransas Wildlife Refuge their burrows may be in areas
with little or no ground cover, but are always where
soft, damp soils afford easy burrowing.
As with the southern short-tailed
shrew, this shrew is slightly venomous and may
occasionally prey on animals larger than itself, such as
mice. More frequently consumed food items are insects,
arthropods, and earthworms.
Females produce two to three litters of
four to six young each year. Breeding season and
reproductive habits are probably similar to B.
carolinensis. B. hylophaga has an average
lifespan of only 2 years.
Remarks. The best way to
distinguish this species from its cryptic relative, B.
carolinensis, is to study the karyotype (number and
morphology of chromosomes). That of hylophaga has
a diploid number of 52 and a fundamental number of 60,
61, or 62; carolinensis has a diploid number of
37-46 and a fundamental number of 44.