Tailspot Cardinalfish

Photo courtesy from Yuri Hooker

Tailspot Cardinalfish (Apogon dovii)

Max. Length: 7.5 centimeters
Length at 1st Maturity: 5.4 centimeters
a value:
b value:
Depth Range: 3 – 45 meters (10 – 150 feet)
Frequency: Abundant in the reefs of the Eastern Pacific Ocean

Photo courtesy from Shorefishes of the Tropical Eastern Pacific Online

In most of the times during your underwater adventures in Cocos island, you will go to the ledges of the reef where a cleaning station can be found and interact with the big boys of the deep. While kneeling down waiting for the sharks to come, you can’t help but observe a group of tiny fish thriving near the side of a rock, crack or crevice. These group of small fish are mostly composed of Tailspot Cardinalfish. But as there are other small fish species that can be found on this very particular habitat, we might as well make sure to describe its bodily feature to make sure that what you are interacting are the Tailspot Cardinalfish.

Aside from its tiny size, you can easily identify a Tailspot Cardinalfish through its compressed body that is oblong in shape. As their name suggest, they have a red-colored body with a large black spot on the tail. Taking a closer look at them allows you to see two white lines inside their eyes and a broad and dusky horizontal stripe that traverses outside their large eyes. Their head is large while their dental system is composed of small serrated teeth that are mostly located on the side.

A Faithful Partner

Photo courtesy from De Jong Marinelife

A partnership between a male and a female is evident in the world of humans and this relationship is not only confined to mammals, but also to some species of fish. As far as the tailspot cardinalfish is concerned, a faithful partnership can be established between a pair of male and female fish.

This long-term partnership starts when a male and female cardinalfish starts its intricate dance of courtship. If you happen to be in a cleaning station in time for their courtship season, you will notice that among its loosely aggregated population, two individuals stands out. Just to give you an idea, the bigger fish is usually the female while the smaller fish is the male. Once courtship is achieved and successful, you will notice that this pair will swim close by to each other which signals the onset of their mating process. This distinct partnership will go on for a few season until both of the individual reaches their life expectancy as this species are short-lived.

Paternal Mouth-brooders

Another species of Cardinalfish showing their mouth-brooded eggs. Photo courtesy from www.quora.com

Immediately after courtship, females will release their eggs in the water which will be fertilized by the males. These fertilized eggs will then be collected by the male and will be stored in its mouth until it hatches. This oral incubation process is called mouth-brooding.

When the eggs are newly fertilized, they look like tiny transparent marbles that are clumped together by fibrous tissue to prevent oral dislodging. But as the eggs grow, they turn in to a fully develop fingerling having a bright orange colored egg. As soon as majority of the eggs are hatched, the host-father fish will spit out its offspring where you can see them already capable of swimming.

Kidding aside, mouth-brooding has its own advantages where the possibility of doing a Caesarean-section operation during delivery is non-existent. And lastly, when you see a mouth-brooding tailspot cardinal, we ask you not to do any jerky movements as this may disturb them and may swallow their eggs.

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Fishbase: www.fishbase.org

IUCN Redlist of Threatened Species: www.iucnredlist.org

Encyclopedia of Life: www.eol.org

Cocos Island Liveaboard Trips for 2019

Due to high demand of liveaboard trips to Cocos island, as early as this year, we are publishing the 2019 trips for you to choose your preferred schedule and prepare for the ultimate diving adventure of your life. Reserve your seat to Cocos Island as they are selling like hotcakes. Schedule of Liveaboard Trip to […]