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Has anyone heard of a janseni having bits of green? Or a red tail being black? Friends of ours have a snake that is mostly black with the face having bits of green. Sold as a G. oxycephala, it was previously purplish as a baby and turned progressively black. Any idea what it could be? What's a way to differentiate the two species? Thanks in advance.
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~Katt

G. janseni
"juvenile janseni have an olive to dull greenish ground colour."
Scutellation:
2 postoculars; 1 2 or 2 3 temporals, 1 large preocular; 9 to 10 supralabials, the 5th, 6th and 7th, occasionally only the 6th and 7th in contact with the eye; the posterior one being a little higher and arching around the eye; the last (9th or 10th) supralabial is distinctly enlarged; 11 to 13 infralabials; loreal narrow and very much elongate; 23 or 25 dorsal, smooth to weakly keeled vertebrally; scale formula 21-23-17-15; 245 to 257 ventrals; 130 to 140 subcaudals; anal plate divided

G. oxycephala
2 postoculars; 2 3 or 2 4, sometimes 1 4 temporals; 1 large preocular, 9 to 11 rarely 8 supralabials, the 5th and the 6th or 6th and 7th, rarely the 6th 7th and 8th or 5th, 6th and 7th in contact with the eye, the last (the 7th or 8th) being distinctly larger and arching aroud the eye; 12 to 14 infralabials; loreal enlarged longitudinally, very rareluy the loreal is fused to the prefrontal as an anomaly; 23, 25, sometimes 27 dorsals (MB), smooth or very weakly keeled on the back; scale formula: 25-23-21-19-17, 23-23-21-19-17-15, 25-27-25-21-19-17, or 27-25-23-21-19-17; 230 to 263 ventrals; 120 to 157 subcaudals; anal plate divided.

All the info are reported from " A Monograph of the Colubrid snakes of the Genus Elaphe", Klaus-Dieter Schultz, Koeltz Scientific Books, 1996

I never had janseni but from your description I think the snake of your friend is a janseni, if possible post a pic
regards
nazzza

Last year the Denver Zoo bred two black janseni together (actually the female quadruple clutched!) What came out of that first clutch of eggs surprised everybody - they were indistinguishable from G. oxycephalum. That is, they were green with a red-brown tail. However they had just a tiny bit of black tipping on the scales and over the first year of growth the black spread progressively. If your friend's snake is a juvie, it could be a black janseni that has not finished going through its ontogenetic change. If it's an adult, it could be a black janseni that is simply not 100% melanistic. In any case, I'm pretty well convinced that "black janseni" are simply an insular melanistic form of G. oxycephalum.

-David

>>Has anyone heard of a janseni having bits of green? Or a red tail being black? Friends of ours have a snake that is mostly black with the face having bits of green. Sold as a G. oxycephala, it was previously purplish as a baby and turned progressively black. Any idea what it could be? What's a way to differentiate the two species? Thanks in advance.
>>-----
>>~Katt
Ophidiophile Farms

I've kept Janseni. I agree with the last two posts....Frank