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Post by jrlaiho on Mar 8, 2011 12:03:52 GMT -8
You are right, I should not say that IT IS a hybrid. However, it is generally considered to be a hybrid because it occurs were tyche and hecla fly together (at least those I know of). Hybrid or not, I would at least not consider it a regular form of tyche. It is far too rare for that (in fact extremely rare here in Finland). An occasional aberration is one possibility (strange colour forms, extreme melanistic forms etc. occur as occasional aberrations among all butterfly species). Another fact that could support the idea of a hybrid is that there are cases were several specimens have been collected together. If it was a rare aberration we would probably have only single records.
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Post by maurizio on Mar 8, 2011 14:49:25 GMT -8
Another fact that could support the idea of a hybrid is that there are cases were several specimens have been collected together. If it was a rare aberration we would probably have only single records. Also hybrids occur very rarely: if you report cases of several specimens collected together, this is against the hypothesis of an hybrid origin of the taxon. |
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Post by jrlaiho on Mar 8, 2011 21:26:50 GMT -8
Maurizio: if you report cases of several specimens collected together, this is against the hypothesis of an hybrid origin of the taxon.
Why? Keeping in mind how many eggs a female lay, the offspring of the female can be more than just one specimen (and usually is, otherwise the population would face extinction). I would rather say that it is likely that we have more than just one offspring from a hybridisation.
Note "several specimens" is perhaps better expressed as a few specimens as we are talking about 2-4 specimens. I'm sorry if this lead to a misunderstanding (10-50 specimens would, of course, be very unlikely as offspring from one female and one hybridisation event).
As you said hybrids occur very rarely, but they do occur in Colias. F. christiernssoni is very rare and there can be decades between observations here in Finland. Of course, aberrations occur rarely and irregularly as well, so it does not exclude this option.
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Post by jrlaiho on Mar 8, 2011 22:05:10 GMT -8
And for those not interested in discussing th tyche-complex, let's get back to the original idea of this post. Here is another nice Colias. Colias sagartia from Iran. Attachments:
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Post by bobw on Mar 9, 2011 2:11:35 GMT -8
The subject of hybridisation has been much discussed in Colias but still seems to be poorly understood. One of the biggest problems in separating species in Colias is that the genitalia are generally very similar, rendering it not much use as a diagnostic feature. This has the side effect of making hybridisation much easier. It has been shown by researchers such as Ae and Lorkovich that several species can be hybridised using artificial methods, including such unlikely crosses as alexandra x interior.
There is certainly one well-documented instance of two species hybridising freely, i.e. philodice x eurytheme; interestingly the hybrids are fertile but the species seem to have a preference for their own kind when pairing, so maintaining the integrity of the two species. Most evidence of hybridisation seems to be in North American Colias, Ferris put forward his "hybrid swarm" hypothesis to explain the repeated occurrence of unusual phenotypes in a population in Alberta where several Colias species fly together; I have several wierd specimens from this locality which can probably only be explained this way. There are many other probable one-off crosses, I certainly have a few specimens for which I can find no other explanation.
However, hybridisation does seem to be overstated in many instances. Many people have said that croceus and erate hybridise regularly in eastern Europe. Whilst there is no doubt that these sister-species hybridise occasionally I believe it is a rare occurrence and the theory is based on a misunderstanding where any specimen intermediate in colour between the two species is called a hybrid. C. erate has a reasonably common orange form (f. chrysodona) and pale specimens are not unusual in croceus, many of these are automatically designated as hybrids. The "hybrid" in Tolman's book is clearly C. erate f. chrysodona.
Bob
P.S. I'm sorry if there are any errors in references but I'm not at home now so this is just from memory.
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Post by wollastoni on Mar 9, 2011 3:36:10 GMT -8
Juha < I love sagartia from Iran. I have few pairs of them.
Didn't know there were some orange females like yours !
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Post by homard on Mar 11, 2011 14:21:58 GMT -8
Nothing beats netting something personally (although some of the few bought specimens I have are Colias). It is tempting sometimes when I see them on EBay  Would you be able to post some pics of your C. meadi? Do you have C. scudderi as well? I'd agree that nothing is better than to collect specimens personally. Alas, the life is too short, so one never could visit every place to collect everything wanted. So here comes exchange or trade to help us Perhaps I'll post here a pic with my series of C. meadii later on. Of C. scudderi I have but a short series |
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Post by homard on Mar 11, 2011 14:49:18 GMT -8
Alexei Have we corresponded? I'm not sure who you are but I thought I probably knew all the people with whom David has been in touch. Bob, If not to consider your request for my price-list (way back in '08) and my reply to it - than no, we have not corresponded It's great, really! Perhaps you were especially lucky, or had a very knowledgeable guide(s) . In addition, from my personal experience, collecting in the mts. of C. Asia is more easy than in Northern Eurasia because of better weather conditions. Our North is unpredictable at all... Thanks for the explanation! Of course, I meant alta. Though for me, it looked immediately as a relative to hyale, not to erate. Alexei |
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Post by homard on Mar 12, 2011 4:30:16 GMT -8
Would you be able to post some pics of your C. meadi? rayrard, For you, here is my series of C. meadii meadii from CO and MT (left to right - 5 columns), then a pair of C. meadii lemhiensis (VI column), a few of C. meadii elis (VII column), C. canadensis (VIII column), and the single male of C. thula (or is it C. boothii - in the light of after all the discussion here ?)  Alexei |
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Post by rayrard on Mar 12, 2011 9:33:18 GMT -8
Would you be able to post some pics of your C. meadi? rayrard, For you, here is my series of C. meadii meadii from CO and MT (left to right - 5 columns), then a pair of C. meadii lemhiensis (VI column), a few of C. meadii elis (VII column), C. canadensis (VIII column), and the single male of C. thula (or is it C. boothii - in the light of after all the discussion here ?) Alexei Thanks alot! I love the orange/green contrast with the ventral surface. I guess these are more orange than the real red ones from overseas. |
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Post by jrlaiho on Mar 14, 2011 0:26:35 GMT -8
A white female of meadii
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Post by jrlaiho on Mar 14, 2011 0:31:00 GMT -8
A white female of meadii Attachments:
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Post by homard on Mar 15, 2011 4:05:30 GMT -8
Juha,
I suppose it's relatively rare? Never got it, despite I had a relatively big supply of C. meadii a years way back... Same should be with our C. hecla at Polar Ural - never collected a white female there...
Alexei
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Post by bobw on Mar 15, 2011 5:32:57 GMT -8
The white female of C. meadii is very rare except in some populations (e.g. Beartooth Plateau and C. m. lemhiensis) where it is more frequent, although still not common.
White females of C. hecla are extremely rare, and probably exceptionally so in sulitelma.
Bob
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Post by jrlaiho on Mar 15, 2011 5:44:41 GMT -8
White females of meadii are rare (or even exremely rare) in most populations, but in some populations (eg. on Bearthooth Plateau) it can be fairly common. Same with hecla. Never found in Fennoscandia, but if we include the Baikal populations of viluiensis into hecla, white females are common.
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