A comparative study of some aspects of the biology of two New Zealand ghost sharks (Elasmobranchii : Holocephali : Chimaeridae): Hydrolagus novaezelandiae (Fowler, 1911) and Hydrolagus sp.A (sp. nov.?)

Abstract

Hydrolagus novaezelandiae (Fowler, 1911) and H. sp.A (sp. nov.?) differ in their dental plates, clasper morphology, fin shape and size, sensory head canals and number of sensory pores. Both show negative allometric growth in some dimensions. H. sp.A differs from known Australian 'species' H. ogilbyi (Waite, 1898), H. waitei Fowler, 1908 and H. lemures (Whitley, 1939) in the shape of the lateral line and clasper morphology. Other features studied in the two New Zealand species include aspects of their reproductive biology, the development of the post-anal pad, food and feeding habits, and their monogenean and digenean parasites. Three new species of the monogenean Gyrocotyle are reported.