Revision of the extinct island-shrews Nesophontes (Mammalia: Eulipotyphla: Nesophontidae) from Cuba

Abstract

Nesophontes is an extinct, shrew-like mammal endemic to the Greater Antilles. Within this genus, the Cuban taxa have a challenging taxonomic history. The dichotomy in the interpretation of species limits arises from the ample size variation observed in skeletal remains. Here, I provide a detailed systematic revision of Cuban species through multivariate morphometric and qualitative analyses. These include discrete osteological characteristics of the cranium, dentary, dentition, humerus, femur, pelvis, and endocranial casts from a wide range of specimens, several maturity levels, and radiocarbon-dated paleontological contexts, all of which can help resolve current taxonomic ambiguities and elucidate the species limits of the Cuban taxa. Furthermore, stable isotopes of carbon and nitrogen were obtained to approximate aspects of diet, habitat, and resource partitioning between the Cuban Nesophontes. Collectively, these analyses support the presence of three species that are divided into two morphotypes. The larger included Nesophontes major and Nesophontes longirostris, whereas Nesophontes micrus is smallest. Morphotypes of N. major and N. micrus showed further intraspecific variation, which could be attributed to sexual dimorphism. Chronologic and geographic variations, at least during the Late Holocene, were quantitatively detected but poorly supported. The isotope signals suggest slight microhabitat segregation between N. major and N. micrus, but overall similar diets. Altogether, these new data provide insights into the morphology and natural history of these peculiar and extinct Antillean land mammals.