I desagree with that...Mine has a blotch, like a continuation of his stripes on his dorsal an is a male...How do I know if it is a male? Because i've seen him trying to mate with my female jd. How do i know if it is a female jd? Because she lays eggs every month, like a clock.... Maybe Im confusing the blotch with something else but..for me , this blotch on the dorsal thing never worked out...
I'm no expert but I find it pretty easy. Here's my female H. carpintis "Escondido". You can see the black in the dorsal on her just as it would be on a texas even though they're different species.