Bothriechis schlegelii: male or female

I need help from experienced Bothriechis keepers in determining the sex of my snake.
When you have a bunch of young snakes available it probably will be not that difficult to sort them out, but I have only one specimen.
The age of this snake is 9 months now and the length is about 30 cm.
I am looking around for a second snake, so then it helps when you know the sex of what you already have.

Probably it helps when you know the number of subcaudals. Counting is not that stressful for the snake when you put it in a clear plastic container for a while and you make a picture from below. On the computer it is easy to make a count afterwards.
At the internet I found that for Bothriechis schlegelii the average number of subcaudals for a male is 56.8 (range 53-61)
and for a female the average is 51.6 (range 33-61).

After counting I learned that the number of subcaudals for my snake is 55/56, because at the end of the tail on one side is one extra scale.
So this number is about the average of a male, but this number of scales is also within the range of females.

When looking at the pictures below, is there anybody who can tell if this is a male or a female?

Maybe some of you have pictures of both sexes available, where you can see the difference clearly, and are willing to upload them here?

Bothriechis schlegelii: male or female Img_7782s

Bothriechis schlegelii: male or female Img_7782s

Bothriechis schlegelii: male or female Img_7786s

Bothriechis schlegelii: male or female Img_7787

I am surprised that there is not a single reaction on my question.

Is it not (yet) possible to determine the sex from these pictures? Is the snake too young to be sure?
If this is the case, please tell me. Or tell your considerations.

Subcaudal scale counting suggests a male, but I guess that popping and/or probing is the only thing that remains...

Hi Anton,
this is a difficult one. Because you've got no comparing animals of the same clutch.
As you stated yourself.
I own one myself wich I bought as a male. It's a slender animal.

Looking at your animal I'm guessing male because its so slender. But then its only 9 months.
I think you'd maybe sit it out and wait untill its maturing.
But I think you're not that patient.

Hi Arjan,

Thanks a lot for your responce and for sharing your considerations. I am always happy to hear a second opinion and it makes sence what you wrote.
Also I think that you are right that one can better wait until the animal is a little older.

I am happy that the animal is not very stressful, because the night after making the above pictures in the empty container, it swallowed a little mouse again Smile

Bye, Anton

Great to hear its eating, it deffinetly needs to build some mussle Wink

.

Since the above discussion my snake slaughed its skin and I took the opportunity to count its subcaudal and ventral scales. The count confirmed the number of subcaudals being 55 and the number of ventrals was 155.
In the publication of Solórzano:
Solórzano, Alejandro, Luis D. Gómez, Julián Monge-Nájera & Brian I. Crother.
Redescription and validation of Bothriechis supraciliaris (Serpentes: Viperidae),
Rev. Biol. Trop., (1998), Vol. 46(2): 453-462).
is a table with scale counts for Bothriechis schlegelii and B. supraciliaris. The numbers for Bothriechis schlegelii are:

Bothriechis schlegelii: male or female Redescription-and-validation-tabel

Bothriechis schlegelii: male or female Redescription-and-validation-tabel

Unfortunately both subcaudal and ventral count numbers of my snake are within the ranges of box sexes.

Because in this table also the mean scale counts and the standard deviation are given I decided to make a plot of the normal distribution of the scale counts. The curves for the normal distribution of the subcaudal scale count is as follows:

Bothriechis schlegelii: male or female Scalecount-subcaudals

Bothriechis schlegelii: male or female Scalecount-subcaudals

Unfortunately this did not learn me new things, because the number of subcaudals of my snake (the green bar) is well within both curves of males and females.

The curves for the normal distribution of the ventral scale count is as follows:

Bothriechis schlegelii: male or female Scalecount-ventrals

Bothriechis schlegelii: male or female Scalecount-ventrals

and this is interesting, becuase the chance that my snake is a female is much bigger than the chance that it is a male. And now I am writing this I realise that I also included the anal scale in the ventral scale count, so in fact the number of ventrals is 154.

It would be interesting when keepers of Bothriechis schlegelii, also count the numbers of scales from slaughed skins, to see where in the curves their snakes are, especially when they already know if the snake is a male or a female. If anybody made a scale count, please, share it with us.

Best wishes, Anton

Verry interesting Anton,

I will look out for sheded skins.
How is its appatite

Hi Arjan, thanks for your interest. Here I upload a corrected curve for the ventral scales. This is because I erroneously included the anal scale in the ventral scale count. So this must be 154 ventral scales plus a single anal scale.

Bothriechis schlegelii: male or female Scalecount-ventrals2

Bothriechis schlegelii: male or female Scalecount-ventrals2

This curve gives the impression that the animal is definitely a female, but in the above table with scales numbers you see that the curve for the males is based on 9 specimens only, while the curve for the females is based on 48 specimens. So I am sure that with a higher numbers of males the curve also will become broader, like the curve for the females...

The appetite of my animal is very good. So far it accepted every mouse that I offered. I offer it a pinky every week, and sometimes after six days already, when I see that the pinky of the week before is devoured.
Why did you ask this Arjan? Do you think that I have to increase the number or the size of the pinkies that I offer?
The age of the snake is 11 month now and the weight is 16 g. I have no idea if this is a normal weight for a schlegelii of this age.
Is there anyone who has an opinion on this?

Thanks, Anton

fantastic information man thanks a lot, very usefull