Do damsels change sex?

Do damsels change sex?

Postby Luis A M » Thu Sep 20, 2007 2:23 pm

Witt states in the book that damsels are protogynous sequential hermaphrodites (female to male sex changers,the opposite to clowns)
Is that so?.Was it based on personal direct observations?
Anybody else ever had damsels changing sex?
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Postby Clownfish75 » Thu Sep 20, 2007 5:42 pm

Luis i am sure i remember reading the OTB (Cryisptera cyanea) will chasnge from female to male in the absense of a male.

but i cant say i have seen any better information than that.

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Postby aomont » Thu Sep 20, 2007 10:20 pm

Hi Luis, I have to fight against this information in my mind everytime a thread on damsels/dascylus shows up. :lol:
I have not read as far as I remember but, if it was a poll I would vote for protogynous as well.;)
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Postby Witt » Thu Sep 20, 2007 10:46 pm

Luis,

There are many documented cases of protogynous sex change in Dascyllus spp. D. trimaculatus and reticulatus for sure, others who knows. I have heard sporadic reports for a few spp. of Chrysiptera and some other genera, but this is a poorly known subject for the pomacentrids. I will see if I can dig up those references. It is interesting in that tank after tank of "female" C. cyanea refuse to show male colouration. I am sure sex allocation is quite diverse in a family as large as the damsels.

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Re:

Postby Luis A M » Fri Sep 21, 2007 2:27 am

aomont wrote:Hi Luis, I have to fight against this information in my mind everytime a thread on damsels/dascylus shows up. :lol:
I have not read as far as I remember but, if it was a poll I would vote for protogynous as well.;)
Anderson.

Sure,males are larger and dominant.Poll would be "do damsels change sex or not"
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Re:

Postby Luis A M » Fri Sep 21, 2007 2:49 am

Witt wrote:Luis,

There are many documented cases of protogynous sex change in Dascyllus spp. D. trimaculatus and reticulatus for sure, others who knows. I have heard sporadic reports for a few spp. of Chrysiptera and some other genera, but this is a poorly known subject for the pomacentrids. I will see if I can dig up those references. It is interesting in that tank after tank of "female" C. cyanea refuse to show male colouration. I am sure sex allocation is quite diverse in a family as large as the damsels.

matt

Matt,I don´t say they don´t,only that reports are few and anecdotical.It was bizarre to me that fish in the same family could change in both ways,though you showed that this happens with pseudochromids.
I bet Chrysiptera is gonochorist.The C.taupou of my avatar was raised and kept alone well into adulthood and never changed to male colour pattern.
Raising a number of fish showing sexual dichromatism could clear the subject.
Now that you´re around could you check my post at: http://synchiropus.com/phpbb/viewtopic. ... sc&start=0
Thanks :D
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Postby Witt » Fri Sep 21, 2007 2:49 pm

Luis,

Sex allocation theory is surely a tricky subject. In scientific literature there are manipulative studies accompanied by histological examination of gonads for only a few species of pomacentrids (Dascyllus reticulatus and trimaculatus). There are a lot of 'anecdotal' suggestions for many more damsels, but this could be difficult to interpret. One would think that if Chrysiptera were protogynous that hints of sex change would be apparent in a tankful of females. It could be that these females are immature or don't hang around long enough in dealer tanks to initiate sex reversal. Sex allocation is much more intricate and confusing than it was once considered. Bi-directional sex change is a pretty cool example. Sex change from the standpoint of dichromatism opens a whole new window on the subject. Pseudochromis steenei, a big bold and beautiful dottyback 'anectdotally' exhibits bi-directional sex change, with a major mode of protogyny. So in theory, the small fish are female before changing sexual function into male. When raised under captive conditions, however, it shows just how tricky all this stuff is. The metamorphic color, is a dusty yellow with some spots. THen, in the juv. phase they take on the color pattern of the male. Seeing a 1" fish with male characteristics is pretty wild. Does this mean that this fish is male? NO/ especially since it is not sexually mature. A lot of fish exhibit changes in coloration through ontogeny. Many fish as juveniles exhibit the terminal color phase before turning into the color denoting their sexual function. So in short, I am sure damsels are protogynous just as they are gonochoristic and protrandric. With Chrysiptera, I think the verdict is still out. My two cents anyway.
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Re:

Postby FuEl » Sat Sep 22, 2007 11:54 am

Witt wrote:Luis,

Sex allocation theory is surely a tricky subject. In scientific literature there are manipulative studies accompanied by histological examination of gonads for only a few species of pomacentrids (Dascyllus reticulatus and trimaculatus). There are a lot of 'anecdotal' suggestions for many more damsels, but this could be difficult to interpret. One would think that if Chrysiptera were protogynous that hints of sex change would be apparent in a tankful of females. It could be that these females are immature or don't hang around long enough in dealer tanks to initiate sex reversal. Sex allocation is much more intricate and confusing than it was once considered. Bi-directional sex change is a pretty cool example. Sex change from the standpoint of dichromatism opens a whole new window on the subject. Pseudochromis steenei, a big bold and beautiful dottyback 'anectdotally' exhibits bi-directional sex change, with a major mode of protogyny. So in theory, the small fish are female before changing sexual function into male. When raised under captive conditions, however, it shows just how tricky all this stuff is. The metamorphic color, is a dusty yellow with some spots. THen, in the juv. phase they take on the color pattern of the male. Seeing a 1" fish with male characteristics is pretty wild. Does this mean that this fish is male? NO/ especially since it is not sexually mature. A lot of fish exhibit changes in coloration through ontogeny. Many fish as juveniles exhibit the terminal color phase before turning into the color denoting their sexual function. So in short, I am sure damsels are protogynous just as they are gonochoristic and protrandric. With Chrysiptera, I think the verdict is still out. My two cents anyway.


Assuming I understand this correctly, a 2" P. steenei exhibiting male colouration might not be male as the male colouration is the terminal colouration? So in P. steenei they actually begin as reddish-orange fish, changing to grey, and changing back to reddish-orange? So in other words, a reddish-orange 2" P. steenei is actually a pseudo-male when it is in fact, female? :shock:
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Postby Luis A M » Sat Sep 22, 2007 6:41 pm

Also,some gobies are said to change sex,Gobiodon and Cryptocentrus.
Young C.cinctus are a nice yellow.But females often change to a banded pattern in grey and brown.The final sex should show the terminal coloration.But I´m not sure if this colour change is not environmental.I have seen pairs where both were banded grey :?
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