batrachos,

Thanks for your response. And by the way, the species involved is the Rubber Boa and not the Rosy Boa.



I have posed this same question elsewhere. So far, no one has even attempted a response let alone pose a solution either with or without the use of subspecific designations. So you stand alone in providing some input and that is appreciated.



At times, I have found myself agreeing with Ron Nussbaum who in a 1974 paper on the species, discarded the then 3 recognized subspecies and simply lumped all Rubber Boas into a single species. Yet that arrangement overlooks the present situation (unknown at that time) where there are two discernable groupings of the species. On the one hand, there is the large morph populations characterized by large size, relatively high ventral and dorsal scale row count. In contrast, there are the dwarf morph populations all characterized by small size and with relatively lower ventral and dorsal scale row counts.



In addition, these two groupings are clustered geographically. Had such information been available in bygone years, the two groups would either have been designated as subspecies or species. However, the present mtDNA results throws a monkey wrench into that scenario. At the present, I can think of two explanation that might tend to be consistent with the mtDNA results.



1) One might argue for retention of the two species, the Southern Rubber Boa and Northern Rubber Boa with the latter being composed of two subspecies as follows: All large morph populations would comprise a northern subspecies and all other dwarf populations (expect those in the San Bernardino and San Jacinto Mts.) would constitute a southwestern subspecies of the Northern Rubber Boa.



2) A second scenario would be to have three subspecies. All large morph populations would belong to the northern subspecies, the dwarf populations in the San Bernardino and San Jacinto Mts. would belong to a southeastern subspecies, and all other dwarf population in S. Calif. would belong to a southwestern subspecies.



Of course, the problem with both scenarios is that they disregard the current vogue of discarding all subspecific designations. I am not knowledgeable enough about how to interpret mtDNA results but the data presented in Javier's paper might suggest additional scenarios as well.



I did not post the longer explanation which indicates all Rubber Boas populations occupy the identical ecological niche regardless of geography. They are all nest robbers mostly preying on small mammal nestlings (shrews, moles, mice, gophers, voles, rats, etc.) Secondly, I have already completed some crosses between dwarf and large morph specimens and size is definitely under genetic control. In addition, maintaining juvenile and subadult specimens of both size morphs under identical laboratory conditions substantiates that size is genetically controlled and not a function of differing environmental conditions.



Re your forum name, are you fondly 'attached' to slender salamanders? Thanks again for your input.



Richard F. Hoyer

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