My Centropyge acanthops harem, African Flameback Dwarf Angel

[OrionN]

My three Flameback were about 1.5 inches. These fish are clearly dimorphic so sexing them is easy. I have a friend who keep a Flameback angel as a singleton for 2 plus year and it is still a female.
from this observation I think they will not turn male unless there is another female around.

 

[Zionas]

I wonder if this applies to most fish? If they are the only one they will most likely remain female? I also wonder if the maximum sizes listed for most species are only for the males (or in the case of Clownfish, the females).

 

[OrionN]

A few picture of my office tank at the end of the forgettable 2020 (I wish that it is forgettable anyway)

 

[Zionas]

Still I think they look amazing. And yes forgettable year indeed.

 

[OrionN]

This is my observation regarding sex of two of the Centropyge angels (Flameback and Flame), and Genicanthus angels (Watanabei).
I keep a single Flame angel in my sump at home for 1+ year, about 18 months or so. She is clearly a female and fair size. I also know of two Flame back angel that was keep as a singleton for 2+ years. Both are large, certainly significantly larger than my Male Flame back. Both of these angels are clearly female. Flame angel and Flameback angels are dimorphic and we can easy tell male from female, so my sex ID is certain in all three of these angels. Large long standing singleton are female, not male.
Also there are many reports that male Genicanthus angels will revert back to female coloration if keep by themselves.

My take on this observation is that these hermaphrodites angels are prototogynous, however the male development will need stimulation from smaller conspecific. Lone angel will not have these stimulation and thus will never become male, and those that already males, will reverted back to females. We certainly can confirm this if we keep a male for long duration and document the reversal of the phenotypic characteristic from male to female. I may elect to do this in the future.

This hypothesis will also explain why some reefer observe placing a smaller angel with a larger angel result in fighting to the death. I think this is the case where the large angel is a female and the smaller angel is a male. The larger female then proceeded exert her dominant and beat up the smaller male. They would be fine if the male survives and eventually change sex to female, but many of the smaller male died prior to complete sex change.

 

[pcon]

This is my observation regarding sex of two of the Centropyge angels (Flameback and Flame), and Genicanthus angels (Watanabei).
I keep a single Flame angel in my sump at home for 1+ year, about 18 months or so. She is clearly a female and fair size. I also know of two Flame back angel that was keep as a singleton for 2+ years. Both are large, certainly significantly larger than my Male Flame back. Both of these angels are clearly female. Flame angel and Flameback angels are dimorphic and we can easy tell male from female, so my sex ID is certain in all three of these angels. Large long standing singleton are female, not male.
Also there are many reports that male Genicanthus angels will revert back to female coloration if keep by themselves.

My take on this observation is that these hermaphrodites angels are prototogynous, however the male development will need stimulation from smaller conspecific. Lone angel will not have these stimulation and thus will never become male, and those that already males, will reverted back to females. We certainly can confirm this if we keep a male for long duration and document the reversal of the phenotypic characteristic from male to female. I may elect to do this in the future.

This hypothesis will also explain why some reefer observe placing a smaller angel with a larger angel result in fighting to the death. I think this is the case where the large angel is a female and the smaller angel is a male. The larger female then proceeded exert her dominant and beat up the smaller male. They would be fine if the male survives and eventually change sex to female, but many of the smaller male died prior to complete sex change.

In client tanks, when I worked in a fish store, I saw many female flames transition to males when kept singly with no other angels present. I have seen a couple not transition when kept alone for several years, but far more transitioned when kept singly, over the course of a few moths to a few years. I have also observed potters, rusty and keyhole angels transition when kept singly, without other angels in the tank. I have seen potters and flame angels kept alone for 5+ years which were male so that makes me question that they will revert when kept alone. just my observations on the matter.

 

[OrionN]

I certainly have specific observation with the numbers of angels that I come I come in contact with. I don’t work at LFS or have a maintenance service so the numbers of fish I come in contact with is small but significant in depth. With flame and Flameback there is no question and very easy to tell if the fish is male or female.
So far I have not seen any exception to my observation. I can only speak of my experiences and how sure I am of the sex of the fish. I certainly cannot say anything about @pcon observations. Hope some people can chime in, even provide pictorial proof.

 

[atoll]

@OrionN
Hi, over the last week I have added 3 C.acanthrops. I believe 1 male and 2 females. I wasnt aware of the differences in anal fin shapes untill I read your post. These are housed in my well stocked 125gallon mixed reef.

At this point I must point out I have been keeping marine fish for nearly 40 years and have kept pairs of Acanthrops and argi in the past which spawned for me.

The way I have always sexed them is via the fishes body shape, males being longer in the body, females stubbier. This has always worked for me when it comes to sexing. I am aware all these fish are born female.

Although I have I have kept a number of pairs of both C.argi and C.acanthrops I have never tried a trio until now. The last of my females was introduced today and the usual chacing began shortly after. This of course is only to be expected.

I have read through all 3 pages of your post with interest and given it's about 3 months now since your last update could you be so kind as to give us an updated on how your trio is doing along with possible spawnings and growth during this period of time?
Cheers.

 

[Zionas]

Hey that’s good to know. How big are your 3 and how big were the spawning pairs you had in the past (of both species) when you purchased them? How many years did you have them?

 

[atoll]

Hey that’s good to know. How big are your 3 and how big were the spawning pairs you had in the past (of both species) when you purchased them? How many years did you have them?

Aimed at me?
I first kept a pair of C.argi around 30 years ago and had them for about 8 years before I broke broke the tank down to move house and sold everything off. I guess the male got to around 2.1/2" the female 2" . When I bought then the female was around 1.1/4" make just 1/4"or so bigger. They spawned within a year of purchase.

when I set my next tank up I bought a pair of C.acanthrops had them about 4 years. They were a similar size to my C.argi. both sets of angles behaved very similar and grew atca similar rate.

 

[atoll]

@OrionN
With regard to the darkening towards the rear of the dorsal fin and the pointed end of the anal fin is that something you notice as the fish matures or are they evident as soon as they transition from female to male so in a short period of time?
Previous to.your thread I sexed my pygmy Angel's purely on body shape and size.

 

[Zionas]

Thanks for the info. I’m glad you managed to make it work. How important do you think is it to have a size difference when pairing 2 specimens?

 

[atoll]

Thanks for the info. I’m glad you managed to make it work. How important do you think is it to have a size difference when pairing 2 specimens?

Am.not so certain about that as an older female could be larger than a young male. Most come in as young fish however so the length of the body and shape is more important than overall size.

 

[Zionas]

Good to know. The smallest I’ve seen in my area are about 1.2”-1.6” (3-4cm) I’ll try to go down OrionN’s route and get 2 in that size range and hopefully it will work out.

 

[OrionN]

@OrionN
With regard to the darkening towards the rear of the dorsal fin and the pointed end of the anal fin is that something you notice as the fish matures or are they evident as soon as they transition from female to male so in a short period of time?
Previous to.your thread I sexed my pygmy Angel's purely on body shape and size.

This is a very clear change, within weeks as soon as I put the three small Flameback angels, all less than 1.5 inches, together.
IME, Flameback Angels are protogynous hermaphodites but can reverse sex change. They are also dimorphic so sexing them is relatively easy. It is important that we don't keep add males together, or add a female that is larger than the male. In these situation, there will be plenty of aggressive fighting with the dominant fish eventually become the male of the harem. However, unless the tank is large with plenty of place where the looser can hide from the victor while he changing from male to female, there will be significant mortality. This seem to be the same, the rule, with Centropyge angels. This is a generalization on my part from personal experiences with C. acanthops, C. loricula, and C. argi, and literature research on other Centropyge angels.

An other observation that I have is that singleton Centropyge seem to remain female, and won't undergoes change sex unless there is another smaller angel are in the territory. I am trying to test this hypothesis right now. I have a single Flame angel in my sump right now for the last 2 years. She was a 1 inch juvenile when I put her there. She is eating well, growing well but remain a female. In an few more years, I will know for sure that sex change in Centropyge is natural progression of development suppressed by the present of a dominant fish, like in clowns, or these sex change require stimulation by the present of a smaller fish. I have this question because I have seen in several instant where large singleton Flameback angel remain female. Once I determine that large flame angel can remain female, I will see how quickly she turn male once I add a smaller female to her tank.

 

[Zionas]

I think I will try for a pair of Flamebacks. The smallest I have seen in my area are 1.2-1.6” in length (3-4cm). If I get 2 in that size range are chances good that they’re still both females and will likely pair up in time? Thanks.

 

[OrionN]

I think I will try for a pair of Flamebacks. The smallest I have seen in my area are 1.2-1.6” in length (3-4cm). If I get 2 in that size range are chances good that they’re still both females and will likely pair up in time? Thanks.

Yes, very quickly like in 2 weeks.

 

[Zionas]

Great. That’s good to know. Good luck with all your tanks.

 

[atoll]

This is a very clear change, within weeks as soon as I put the three small Flameback angels, all less than 1.5 inches, together.
IME, Flameback Angels are protogynous hermaphodites but can reverse sex change. They are also dimorphic so sexing them is relatively easy. It is important that we don't keep add males together, or add a female that is larger than the male. In these situation, there will be plenty of aggressive fighting with the dominant fish eventually become the male of the harem. However, unless the tank is large with plenty of place where the looser can hide from the victor while he changing from male to female, there will be significant mortality. This seem to be the same, the rule, with Centropyge angels. This is a generalization on my part from personal experiences with C. acanthops, C. loricula, and C. argi, and literature research on other Centropyge angels.

An other observation that I have is that singleton Centropyge seem to remain female, and won't undergoes change sex unless there is another smaller angel are in the territory. I am trying to test this hypothesis right now. I have a single Flame angel in my sump right now for the last 2 years. She was a 1 inch juvenile when I put her there. She is eating well, growing well but remain a female. In an few more years, I will know for sure that sex change in Centropyge is natural progression of development suppressed by the present of a dominant fish, like in clowns, or these sex change require stimulation by the present of a smaller fish. I have this question because I have seen in several instant where large singleton Flameback angel remain female. Once I determine that large flame angel can remain female, I will see how quickly she turn male once I add a smaller female to her tank.

I was under the impression that once a female turns to male it can't revert back to female no matter what.

 

[jaganshi066]

This is a very clear change, within weeks as soon as I put the three small Flameback angels, all less than 1.5 inches, together.
IME, Flameback Angels are protogynous hermaphodites but can reverse sex change. They are also dimorphic so sexing them is relatively easy. It is important that we don't keep add males together, or add a female that is larger than the male. In these situation, there will be plenty of aggressive fighting with the dominant fish eventually become the male of the harem. However, unless the tank is large with plenty of place where the looser can hide from the victor while he changing from male to female, there will be significant mortality. This seem to be the same, the rule, with Centropyge angels. This is a generalization on my part from personal experiences with C. acanthops, C. loricula, and C. argi, and literature research on other Centropyge angels.

An other observation that I have is that singleton Centropyge seem to remain female, and won't undergoes change sex unless there is another smaller angel are in the territory. I am trying to test this hypothesis right now. I have a single Flame angel in my sump right now for the last 2 years. She was a 1 inch juvenile when I put her there. She is eating well, growing well but remain a female. In an few more years, I will know for sure that sex change in Centropyge is natural progression of development suppressed by the present of a dominant fish, like in clowns, or these sex change require stimulation by the present of a smaller fish. I have this question because I have seen in several instant where large singleton Flameback angel remain female. Once I determine that large flame angel can remain female, I will see how quickly she turn male once I add a smaller female to her tank.

My flameback was the only angels in a tank and stayed female like you said! Now I’m pairing her but she’s a little big haha