'Bastard Blue' Fish Species Fight Rivals by Kissing

A species of fish known for its aggressiveness and elusiveness finally gets official recognition from scientists.

Identified as Plectorhinchus caeruleonothus, more popularly known as the blue bastard, this fish has long been known to Australian fishermen.

"Queensland Museum scientist Jeff Johnson, who identified the species from photos taken last year by a Weipa fisherman, has formally christened it Plectorhinchus caeruleonothus - a direct Latin translation of the colloquial name anglers bestowed on a fish famously difficult to land," The Guardian reported.

"Caeruleo is blue and nothus is bastard. That was the origin of the name applied by fishermen for many years and I thought, why should I argue with that? It seemed like a perfect name for me," Johnson was quoted as saying. "I wondered what the reviewers of the paper would say about it but they both agreed it was quintessentially Australian and we should go ahead."

The blue bastard can grow to over 3 feet and lives in shark-infested waters mostly in the northern part of Australia, which is partly why it is difficult to catch. It belongs to a group of fish identified as "sweetlips" due to their unusually large lips.

"Previously, Blue Bastard was confused with another type of sweetlips by scientists, but now it's known that the other species doesn't have the characteristic dozen dorsal spines," Discovery explained.

Interestingly, as babies, the blue bastard sport yellow and dark stripes. They later change their scales to the distinctive color they're famous for.

There had been reports that the blue bastards tend to engage in "passionate kissing" near the surface of the water. However, it was later found that male blue bastards use the "kissing" to fight each other.

"They'll come to the surface and struggle away for minutes at a time ... it's a behaviour that's unique to this species among sweetlips," Johnson revealed, as noted by Mashable.

"I've spoken to a few of the guys (fishermen) and they say they (the fish) often engage in these episodes and they're pretty serious about it too," Discovery quoted Johnson as saying. "One fish will see another one approaching in the distance and he'll just make a beeline for the other guy and they'll go at it hammer and tongs."

If you're wondering whether they make a good dinner, you'll get a negative response. Although some members of the sweetlips group are just fair culinary prospects, the blue bastard won't probably be tasty, Johnson suspected.

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