Colias from Beijing

[luehdorfia]

This Colias is from the outskirts of Beijing, 15th September 2016, in a real estate development in some small hills where a few undisturbed patches were left, around 100m.a.s.l. flying around noon. Next year probably almost all the fields will be gone. Altogether I didn't see many undisturbed meadows or grassy places in Beijing. Up in the hills around Beijing it is a little bit better but not much.
I think it should be a Colias poliographus, but since it is one of my first Colias I do not know for sure. Also which subspecies would be applicable?

[bobw]

It is poliographus. This species is very common and widespread; it's a culture follower so its range is expanding all the time as it follows the foodplants planted by man, similar to croceus and erate further west.  Because of this, even though several have been described, I would not recognise any subspecies - they all look identical in series.

Bob

[luehdorfia]

Is poliographus and erate syntopic? Do you happen to have erate and poliographus from north China to compare them?
I will definitely look out for some more exciting Colias this year, there is one mountain in Beijing where they have Colias heos, and if I can escape from work long enough I will go to Gansu, Qinghai, or Tibet. Xinjiang is a bit too dangerous since several areas especially remote ones are closed for foreigners because of Islamists.
Thanks again and if you know some good places where you have been in China I'd love to hear about them.

[bobw]

C. poliographus was traditionally considered to be a ssp. of C. erate, although Alpheraky and Grum-Grshimailo suggested they were separate species over 100 years ago!  It is almost impossible to separate them by phenotype (although those with solid borders in the male are nearly always erate) but there is geographical separation so I tend to agree with those that consider them to be separate species.  Possibly more research into early stages, female genitalia or DNA may help to prove it one way or the other.

C. erate flies as far east as the Chinese Tien Shan and southwestern Mongolia with rare strays into the Russian Altai; in eastern Mongolia only poliographus is found, straying into Tranbaikalia.  Therefore all Chinese specimens except those from the Tien Shan would be poliographus.  Both species are culture followers, so where we plant fields of leguminous crops such as Alfalfa or Soya, the butterflies will follow.  Because of this poliographus is expanding rapidly to the west and south, and erate is expanding to the east and north so that their ranges are starting to meet and will soon overlap; as they are clearly at least sister-species they could easily start to interbreed in a similar way to C. philodice and eurytheme in North America.

C. erate is also rapidly expanding eastwards so it is now quite common in Austria and Bavaria where it was previously only a rare vagrant.  This is bringing it more regularly into contact with C. croceus, adding fuel to the unfounded rumours of hybridisation between these two species - nearly all "hybrids" are misidentifications of the fairly common orange form of C. erate - f. chrysodona.

As you say, C. heos is found not far away from Beijing and C. chrysotheme is found in NE China, as far south as Shanxi province.  The common C. poliographus and C. fieldii are found nearly everywhere but for the best Colias (and Parnassius) you have to go to western China.  There are some good species in Xinjiang, Szechuan and Tibet but the best provinces are Qinghai and Gansu.  I only went there once, in 2004, but it was a particularly bad season after a prolonged drought and we saw very few Colias or Parnassius. I have data about some good places so if you're thinking of going there and want to know more, PM me.  By the way, be careful when collecting in China; collecting by foreigners is strictly forbidden (although it's allowed for locals) and I know of several people who have had brief stays in jail.

Bob