Barred Knifejaw - a new species record for Australia

This Barred Knifejaw, Oplegnathus fasciatus, is a new record for Australia. It was speared by Angus McCook in June 2023 off Tea Gardens, New South Wales.

Thank you Vin Rushworth for uploading the observation.

Prior to this observation only one species of Oplegnathus was known from Australia -Oplegnathus woodwardi.

Luckily for us, Angus' fish is an adult male that has the distinctive black colouration around the mouth and eye typical of the Barred Knifejaw. The species also has more vertical bars than O. woodwardi, a high soft dorsal fin, and dusky coloured pectoral, pelvic and caudal fins.

Interestingly the species has also been recorded as an introduction to New Zealand. It also occurs in Japan, Korea, Taiwan. Hawaii and the Mediterranean Sea, where it has been introduced.

Angus stated, "I was competing in the Australian pacific coast championships. I had just lost a large yellowtail kingfish and decided to scrounge for some smaller species in Esmeralda Cove on Broughton Island. While scoping around a large boulder edge where I had previously found a variety of species, I approached a school of Black Drummer swimming out in the open. As I got closer, I noticed one fish looked different to the rest, later realizing what it was as my father couldn't stop raving about this same fish from a previous dive in the same spot just a few months prior. Once I approached the school, the Knifejaw became very skittish, swimming erratically, separating itself from the school. I slowly followed along the surface until it eventually sought refuge in a cave. I patiently hid out of sight on the other side of the cave and waited for the fish to emerge. After spearing the fish, at the competition weigh-in I found out how unknown this fish was and the likelihood of it being an Australian record. It makes me very proud to be a part of history."

References:

• Nakabo, T. 2002. Fishes of Japan: with pictorial keys to the species. Tokai University Press. Pp 2428.
• Roberts, C., Stewart, A.L. and C.D. Struthers. 2015. The Fishes of New Zealand. Te Papa Press. Pp 1748.