Lyretail Anthias – Pseudanthias squamipinnis
Welcome to the Findex, an in depth look at the fish and coral life in the sea. We will take a look at the fish that everyone will see while they are diving but maybe don’t know much about or don’t get as much time in the spotlight as the big stuff!
Today’s fish is a real coral reef staple. They can often be seen in huge shoals sweeping over the reef, adding a beautiful splash of bright orange to the coral wall.
The Lyretail Anthias, also known as the Lyretail Coralfish, Scalefin Anthias or the Sea Goldie, are small members of the Serranidae family. This family also includes much larger fish like groupers and bass, one of the reasons why these fish are called basslets in some parts of the world.
What’s in a name?
The Lyretail Anthias gets its name from the shape of its tail fluke. A lyre is a U shaped string instrument, much like a harp, commonly used in ancient Greece, Egypt and northern Africa. This U shape can be seen in the tail fin of the fish. Finally, the word anthias just means fish.
Habitat and distribution
Lyretail anthias can be found in shoals ranging in size from just a few individuals to huge groups over 2,000 strong. They are found covering the face of the reef, in lagoons, over bommies, down walls and around pinnacles. This species can be found throughout the Red Sea, Indian Ocean, around Australia and in the Pacific Ocean up as far as Japan. Oddly for a fish with a range like this, it is not found in the Persian Gulf or in Oman. If you are in the Red Sea from December to February, you can watch them spawning in huge numbers at around sunset.
Looks that kill
Most of the time when you see Lyretail anthias they will be ranging from bright, sunburst orange colour to a lemon yellow. Most will also have a streak of colour from their eye down to their pectoral fins which ranges from vivid red to deep violet with an underscore of electric blue. These fish are the females. The males are stunning to see and they look like another species all together! Their fin rays are elongated and their bodies are a bright reds and purples, all to look very impressive to the females. This is called sexual dimorphism, where the two sexes of a species look totally different. The males are also much bigger than the females, 15cm instead of the females 7cm.
When you see a large group of Lyretail anthias, rather than being one huge shoal it is actually many smaller harems all grouped together. One male fish may keep as many as 10 females to breed with in his territory on the reef. The size of his territory will vary based on how tightly packed the other harems of lyretails are, from just 0.5m2 up to 3m2. Lyretails are a species that are protogynous hermaphrodites, which means that they are all born one sex and change to another to react to a change in their lives or environments. These fish are all born female and the strongest female changes sex to being a male. When the male dies, the next strongest female changes sex to male and the process repeats itself. Many fish show this life strategy, the most famous species being the ocellaris clownfish (or Nemo!) but we’ll talk about them in another article.
Life on the reef
As already mentioned, Lyretail anthias can be found all over the reef. They can be aggressive to other species that enter their territory with a quick nip to the fins to dissuade any would be invader. They are harmless towards divers, moving around and out of the way for you but quickly returning to their spot after you have gone. Swimming amongst them you can often find a Midas blenny, Ecsenius midas, which will change its colour to hide in the shoal. These can be hard to tell apart at a distance but when you get close you can notice a black spot on the belly of the blenny that the anthias don’t have.
Many local divers will tell you that watching the anthias is the best indication of which way the current is flowing. On my most recent trip to the Red Sea I can confirm that this is true. Lyretail anthias will swim facing into the current as this is the best and easiest way to get as much food as they can, picking at zooplankton and algae as it drifts past. As you look up the reef, any changes in the currents can be easily spotted by watching the anthias.
As they are most active during the day, they can be hard to spot at night but if you look in and amongst the coral, you can see them sleeping and hiding from predators.
I have been fortunate enough to see these little stunners all over the world but my most recent outing to the northern Red Sea was full of them. Most of the reefs we visited had huge populations of them but none were as packed out as Ras Mahammad. Many of the wide angled photos we took were full of these fish, adding ace splashes of orange to the multi-coloured coral vistas. If you get the chance to dive on a reef with them, just sit and watch. It can be very rewarding to see the social interactions between these fish, establishing a pecking order and expanding their territory. Often it’s the smaller fish like these ones that really add to the character of a reef ecosystem and it’s a pleasure to hang out with them.
The bottom line
I travelled on the Whirlwind doing the Wrecks and Reefs itinerary in the northern Red Sea to see these fish. They can be seen year round in this location as well as the Indian and Pacific regions on any surface with coral on it. They always make me smile and complete any reef photo I take.