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This question of subspecies integrades of monkey scincid Corucia zebrata will be …
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The question of intergrades between the main archipelago monkey skink: Corucia zebrata zebrata - (Czz) and the North Solomon monkey skink: Corucia zebrata alfredschmidti - (Cza), has been discussed. The three main tracks of this question are: If Intergrades exist... A). Could this have happened naturally in the original ecosystem between random chance introductions of Cza and Czz through natural means such as rafting episodes? B). Could Wild Corucia been distributed across the Bougainville Strait between Bougainville and Choiseul by the Solomon native human contingent? C). Are the intergrades a result of pairing of Corucia in captivity by human orchestrated introductions, whether planned, by random chance, or in pairing desperation. Track A: As stated in Subspecies comparison of the Genus: Corucia, A semi Wallace line of genetic distinctiveness in size and genetic diversity is clearly evident. If there was free natural exchange across the Bougainville strait, The differences would be much more watered down. A Cza Corucia from Bougainville or a Czz from Choiseul could be conceived as rafting on a log from Bougainville to Choiseul or from Choiseul to Bougainville. Rafting is well known as a means of distributing species and creating new ones. For instance: in the lizard world the common green iguana - Iguana iguana has by rafting, established new populations and species such as in the Galapagos Island archipelago. Evidence of this across the Bougainville strait as of this date, does not reflect this. Another point to consider is the strength and direction of the Bougainville current which further gives credence to this being a natural barrier. The wind and current difficulties in navigation are mentioned in Thirty Years in the South Seas - Richard Parkinson - 1999. Track A Conclusion: Could rafting have occurred to introduce the two species- Highly doubtful. Track B: Solomon native humans do have a market for Corucia for food and shipments from one island to another are possible. Also possible are accidental or deliberate introductions of one island Corucia to another. Again, as of this date, Imports from the Solomons as well as research by Parker, Balsai, Gray and Kohler - shows no evidence of naturally occurring integrades of Corucia. Track B conclusion: Are there man induced integrades of Cza and Czz in the Solomons? Not Likely. Track C: Captive bred integrades of Corucia. As subspecies, it is feasibly possible to breed Cza and Czz. There has been some genetic drift and there is behavior differences noted from the two subspecies. However, a pairing could produce young. The time honored classification of what is the demarcation of two species is that any young produced are considered 'mules' and cannot reproduce. As subspecies: A Cza/Czz offspring should not only be viable but also be able to produce young. The genetic drift as subspecies would make the Czz/Cza hybrid potentially a contributor of possible miscarriages and deformities. A Czz/Cza hybrid would be identified by a mixed combination of features some from one subspecies and some from another such as Scleral color, mixture in parietal scales, body scalation, etc. Track C Conclusion: Could Captive bred subspecies integrades of Corucia exist? A possibility. A documented case remains to be seen.
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