I have them also and they never seem to want to sit at the front glass
sideways so I can tell. :) Fortunatly they should display different
coloration especially in the dorsals. The male dorsals should be a dark
blackish blue color with the front most dorsal having a yellow stripe at the
top and the rear most dorsal having a white stripe at the top. The female
may have a tiny bit of coloring on the dorsal but it shouldn't be nearly as
bright and usually only a spot of it.
I've also noticed in a tank full of males and females that the lower ranking
males will not be quite as colorful as the higher ranking males, and in my
observation as the male reaches full maturity they don't seem to be as
mottled in the body color as the female. To me they seem more of a solid
color where the female stays very mottled.
I never really looked to see if there was any differance in head size as the
coloration pretty much gives them away. I notice teh females, as with many
fish, tend to be a little more plump too.
Hope this helps,
On Fri, 08 Aug 1997, jgrylls at bendigo.net.au (John Grylls) wrote:
>I have recently purchased a nominal pair of Coward Springs desert
>gobies, the "male" is about 40-45 mm in length, and the "female" is
>5-10 mm shorter. They quite are similar in appearance and behaviour,
>sparring and displaying on occasions.. The larger fish has a slightly
>more yellow head, and I think that I can convince myself that his head
>is flatter and proportionately larger, but there is not much in it.
>Their differences could be explained by sex, but I suspect it could
>also be explained by differing levels of maturity. Neither fish is
>sufficiently mature for genital papilla differences to be apparent.
>Any opinions would be greatly appreciated.
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