Physical characteristics

Judging from skeletal remains, Nesophontidae closely resembled the more generalized species of the soricid shrews in appearance and morphology, with some minor variation due to isolation and adaptive evolution. Structurally, they departed little from the standard shrew body plan, except for size variations. All had typically long, narrow skulls, long and mobile snouts, perhaps more moveable than those of soricid shrews, small eyes, and a tail about as long as the body. Each of the four feet carried five fingers and five toes, each toe bearing a claw.

The exact body dimensions and weights of the Ne-sophontidae species can only be estimated, since their remains are merely skulls and isolated postcranial (non-skull) bones. Judging from these remains, Nesophontes edithae, the Puerto

Rican nesophontes, was the largest species, with a skull length of up to 1.7 in (44 mm), a femur length of 1.0-1.1 in (27-28 mm), a head-body length of 6.3-7.5 in (160-190 mm) and an estimated living weight of 6.4-7.1 oz (180-200 g). It was about the size of a chipmunk or laboratory rat, although it probably had a more lithe build. N. zamicrus, the Haitian ne-sophontes, was the smallest species.

Hispaniola was home to three native species of Nesophon-tidae, large, medium-sized, and small. The largest species was about two-thirds the size of N. edithae, while the smallest was about the size of a large soricid shrew. There was a similar, size-ranked array of three nesophontid species on Cuba, the sizes about the same as those of the Hispaniolan species.

Evidence of sexual dimorphism was observed in skeletal remains of Nesophontes edithae, male skulls being larger than female, but size disparities could also be due to age differences. Nevertheless, the case for sexual dimorphism among the nesophontids has recently been reopened.

Nesophontes sp. (Illustration by Bruce Worden)

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