Poster presentation 12th International Mammalogical Congress

Genital bones: Taxonomic distribution and morphological diversity (#673)

Suzanne G Strait 1
  1. Marshall University, Huntington, West Virginia, United States of America

Many female mammals have a bony baubellum within their clitorides, while males have a homologous penis bone called a baculum. Although most extant mammalian species possess os genitale, our knowledge of them is incomplete. Figures and descriptions of these bones in lipotyphlans are essentially non-existent, although comparative anatomy books routinely mention them. The literature on baubella is even more depauperate and have only been well figured and described in squirrels. In this study, the taxonomic distribution and morphology of os genitale were studied at three museums (USNM, MNHB, AMNH). All of these osteological collections contain more bacula than baubella. Bacula representing a total of 47 species of carnivorans, 17 rodents, 12 primates, 2 lipotyhlan, 1 chiropteran where found, but only one carnivoran (Lontra) and one rodent (Tamias) were found to include baubella. Very few specimens were found in main collections associated with post-crania, most were housed within special genital collections. To examine the potential preparational artefacts in osteological collections of os genitale being absent in smaller taxa, an x-ray study was conducted. A PaxScan 4030R flat panel digital radiography was used to image female and male wet lipotyphlan specimens (both whole specimens and isolated dissected genitalia). This imaging technique was robust in picking up fine skeletal detail except in whole hedgehogs, whose spines resulted in excessive background noise. A total of 79 specimens, representing 28 genera, were imaged including solenodontids, soricids, talpids and erinaceomorphs. No baubella were observed and bacula were only variably found in Crocidura fulliginosa and Talpa europaea.