RS:

Besides the question of ancestral type, what geological events isolated these two forum long enough so that when conditions returned so that their distributions became parapatric and probably sympatric, that they had diverged to the point that they no longer interbreed(or so it seems)?



Of the several hundred preserved specimens examined and over 1700

lives specimens (mostly from Oregon) I have examined, none exhibited intermediate traits. The closest that such an situation exists is in the 7 preserved specimens from high elevation in Tulare County. Three additional specimens of the Tulare population were found in 2002 with one being examined after it had been preserved and two live specimens (which I have since donated to CAS). This population resides in habitat very similar to the Forest Sharp-tailed Snake and also exhibits a relatively long tail and high caudal count. However, the range of both traits overlap C. tenuis and not the Forest Sharp-tailed Snake.



Recent mtDNA results show that this Tulare population does diverge considerably from C. tenuis but not like the divergence shown by the Forest Sharp-tailed Snake. So there appears to be a connection between forested habitats and longer tails/higher caudal counts.



There were about 65 - 75 preserved specimens of the Forest Sharp-tailed Snake in all collections which provided a base upon which to identify a reasonably amount of its distribution. With the bulk of preserved specimens being C. tenuis, its distribution is far better identified.



From habitat association, I would expect the Forest Sharp-tail to eventually be found in the coniferous forests in Marin County and through much of Del Norte County in Calif. It has only been identified from three Oregon counties of Curry, Coos, and Douglas. But considering habitat association, I expect it will eventually be found in Jackson, Josephine, and Lane Counties. It may possibly exist further north in the coniferous forested habitats of Benton, perhaps Lincoln counties on the west side of the Willamette Valley and perhaps Linn County on the east side of that valley.



The Common Sharptail (C. tenuis) is far more widespread occurring on some of the islands in Puget Sound and SW corner of Vancouver Island, in the Tacoma region of W. Wash., in eastern Washington due east of Seattle, and along the Columbia River from at least Lyle, Wash. opposite The Dalles, Oregon to Carson, Wash. west of Hood River, Oregon. I would not be surprised that the species may eventually be found is suitable habitat south of Tacoma all the way down to Vancouver, Wash.



In Oregon it has been documented in Wasco County east of Mt. Hood and in all interior counties from Yamhill south to the Calif. border. I am certain it will eventually be found in other counties as well. When I began my study, Contia (both species)had been documented from 8 counties and I increased that number to 11. The species is so obscure that most biologists have never heard of it let alone be able to identify the species. There has been one full article published on the species (Cook, 1960). In Calif. C. tenuis has a fairly large distribution from San Luis Obispo County northward on the coastal side and Tulare County northward on the western side of the Sierra plus a number of interior counties.



Concerning the subject of interbreeding, the two size morphs of Charina bottae readily cross. What mechanism has kept one morph from overwhelming the other (where they meet) is another great question for speculation. I have one idea in that regard.



I have completed a couple of crosses between dwarf male X large morph females. I currently have two surviving offspring from one of those crosses and both (one male and one female) are now adults. In the next year or so, I plan on making the reciprocal cross of dwarf female X large morph male. Will also backcross the hybrid female X dwarf male and hybrid male X dwarf female.



Richard F. Hoyer

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