Description of a new genus and species of miniature monacanthid fish from the Seychelles and Marshall Islands

WA Museum Records and Supplements | Updated 6 years ago

ABSTRACT – A new genus and species of monacanthid fish, Enigmacanthus filamentosus, is described from three specimens, one from the Seychelles in the Indian Ocean and two from the Marshall Islands in the Pacific. It is characterised by the structure and positioning of its epineural ribs (distal extremities branched or expanded, ribs commencing on the third abdominal vertebra). The new taxon has no apparent close relatives, but appears most similar to Paramonacanthus, particularly in body shape. However, it lacks the distinctively elevated soft dorsal and anal fins in the male of Paramonacanthus, as well as having no sexual dimorphism of the osteological structures supporting these fins. Like members of the monacanthid genera Rudarius and Acreichthys, the new taxon matures at sizes smaller than 30 mm SL, and may be categorised as another miniature representative of the family.