Hybridisation is the creation of viable offspring between two taxa and has been widely recognised in both marine and freshwater fishes. The occurrence of hybridisation between chondrichthyans, however, is a relatively recent discovery and has only been documented in a few species. Here we provide evidence of hybridisation between two sawshark species – the common (Pristiophorus cirratus) and southern (P. nudipinnis) sawshark – which co-occur in the waters of southern Australia.
Specimens of both species collected throughout Australia were subject to mitochondrial DNA analysis, with the majority producing sequences corresponding to their field identification. One individual from Tasmania, however, had a mismatch in its field identification (identified morphologically as P. nudipinnis) and molecular identity (possessed P. cirratus mitochondrial DNA). To resolve species identity, genotyping with nuclear single nucleotide polymorphisms was performed. Our analyses show that this individual represents a first-generation hybrid between the two sawshark species. Morphometric data indicate that this female had grown to adult size and may have been sexually mature. This shows that hybrid offspring can survive to adulthood in the wild. These results provide new insights into the reproductive biology of this understudied group of sharks and adds to the number of chondrichthyan species known to hybridise.