No abstract

A total of 2 077 records of approximately 49 000 small cetaceans, including dedicated and incidental sightings and specimens, was analysed to define distribution patterns of the 28 species found within southern African waters. Distribution analyses reveal distinct component patterns, including cosmopolitan (found in all waters) and pelagic cosmopolitan (found in all pelagic waters) components, tropical, subtropical and warm temperate components of the Agulhas Current system, an Agulhas Bank component, a South and East Coast inshore component, and West Coast neritic and pelagic components. While the offshore distribution appears to be determined by water depth, possibly through distribution of the principal prey, longshore distribution appears to be determined by water temperature. The high diversity of small cetacean species found within the relatively small study region results from the wide range of zoogeographic components present. These components arise from the wide range of water temperature resulting from the warm Agulhas Current and the upwelling Benguela system.Altesaam 2 077 boekstawings van sowat 49 000 klein walvisagtiges, doelgerigte en toevallige waarnemings en eksemplare ingesluit, is ontleed om die verspreidingpatrone van die 28 spesies wat binne Suider-Afrikaanse waters aangetref word, te omskryf. Verspreidingsontledings toon duidelike patrone van komponente, met inbegrip van kosmopolitiese (in alle waters aangetref) en pelagies kosmopolitiese (in alle pelagiese waters) komponente, tropiese, subtropiese en warmgematigde komponente van die Agulhasslroomstelsel, 'n Agulhasbankkomponent, 'n Suidkus-en Ooskus-aanlandige komponent, en Weskus-neritiese en pelagiese komponente. Die aflandige verspreiding word stellig deur waterdiepte bepaal, moontlik deur die verspreiding van die hoofprooi, maar kuslangse verspreiding word skynbaar deur watertemperatuur bepaal. Die groot verskeidenheid van klein walvisspesies wat binne die betreklik klein slUdiegebied gevind word, is die gevolg van

DNA sequences from orthologous loci can provide universal characters for taxonomic identification. Molecular taxonomy is of particular value for groups in which distinctive morphological features are difficult to observe or compare. To assist in species identification for the little known family Ziphiidae (beaked whales), we compiled a reference database of mitochondrial DNA (mtDNA) control region (437 bp) and cytochrome b (384 bp) sequences for all 21 described species in this group. This mtDNA database is complemented by a nuclear database of actin intron sequences (925 bp) for 17 of the 21 species. All reference sequences were derived from specimens validated by diagnostic skeletal material or other documentation, and included four holotypes. Phylogenetic analyses of mtDNA sequences confirmed the genetic distinctiveness of all beaked whale species currently recognized. Both mitochondrial loci were well suited for species identification, with reference sequences for all known ziphiids forming robust species-specific clades in phylogenetic reconstructions. The majority of species were also distinguished by nuclear alleles. Phylogenetic comparison of sequence data from "test" specimens to these reference databases resulted in three major taxonomic discoveries involving animals previously misclassified from morphology. Based on our experience with this family and the order Cetacea as a whole, we suggest that a molecular taxonomy should consider the following components: comprehensiveness, validation, locus sensitivity, genetic distinctiveness and exclusivity, concordance, and universal accessibility and curation.