Interesting post there Bob,



Id like your full citation if you dont mind making things easier for me.



You are correct not only about the venom/feeding angle but virtually every other aspect of Diadophis aut-ecology is unknown across their range. My [& perhaps others] hypothesis using that term figuratively [w/o data!] is that the red-tail-coiling group is venomous & are a seperate spps from the yellow ventered non tail coiling group. I dont doubt, as sibling spps., they intergrade.... though Im unaware of this.

What might really be wild is to discover one or more of the red-tail-coiler populations are in fact non-venomous mimics!

Another difficult concept for me is to reconcile is that certain blackheaded snakes [Tantilla ex. nigriceps]....appear to be mimicking Diadophis.



I look forward to interpreting my eventual feeding trials with color sensitive predators such as shrikes & roadrunners.

The Nightsnakes [Hypsiglena] appear to employ constriction or some sort of "para-constriction" while envenomating serpent prey, so while constriction is known in xenodontines, its interesting that despite others observations such as yours, I've never observed this with a substantial number of feeding trials w/regalis.



Thanks for posting, John Gunn







Posted by: BobHansen at Wed Nov 17 14:51:41 2004 [ Report Abuse ] [ Email Message ]

Just to follow up on the constriction angle with Diadophis...We published a note a couple of years ago in Herp Review concerning an observation of an adult Diadophis in CA found constricting a plethodontid salamander. The whole business of whether Diadophis envenoms prey across its range is unstudied. Regals are obviously venomous and I suspect that ringnecks from other parts of the range are too--it's just that they don't attain the impressive size of regalis and don't feed on other snakes--so detailed observations of feeding have not attracted much attention from careful observers. My hunch is that ringnecks that employ constriction do so not in the conventional sense (which is to kill prey before ingestion), but rather use constriction to subdue prey in order to facilitate envenomation/ingestion. But, they are great animals, aren't they?



Cheers,



Bob Hansen

rwh13@csufresno.edu

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