Identification of Orthomiella rantaizana and O. pontis

[DaveChiangMai]

Typical examples of Orthomiella rantaizana and O. pontis seem to be straight-forward to separate. However, I frequently find my observations and photos seem to look intermediate between the two, and I can find no good way of telling them apart.

Pointers to identification are given in Pisuth's book mentioning the straighter termen in rantaizana, though specimen photos on Yutaka and in Kimura do not always show this well, so does not seem to be a reliable way to tell them apart. Probably the most useful differentiation is background colour? Paler on pontis. However, some paler individuals appear to have rather dark markings and look rather dark at the base of the base of the hindwing. It's quite confusing.

I would be interested in any useful feature to separate them, and comments on the identities of these photos (all taken at high altitude on Doi Pha Hom Pok, n Thailand).

Only image 2 would I call a definite O. pontis. The others all have features pointing to both as far as I can see.

Many thanks.

Image 1.
25731

Image 2.
25732

Image 3.
25733

Image 4.
25734

Image 5.
25735

Image 6.
25736

[Psyche]

This is very difficult & confusing.

It is probable there is only one species O. pontis.
It is necessary to look at pontis in India where rantaizana is absent & to look at rantaizana in Taiwan where pontis is absent.

O. pontis; UnH markings fairly sharp & defined. FW postdiscal & cell marks should be present.
Colour veriable & FW shape generally more rounded in the male. Addendum: Ground colour pale & markings typically contrasted.
https://www.ifoundbutterflies.org/media_images/OrthomiellaPontis/OrthomiellaPontis_KrushnameghKunte_an395.jpg
http://www.flutters.org/home/photogallery/plog-content/images/butterfliesbrnbspnbspnbsplycaenidae-the-blues-br/subfamily-polyommatinae-brnbspnbspnbsp-genus-orthomiella---straightwing-blue/straightwing_blue_1_anurag_mishra_2.jpg
https://www.ifoundbutterflies.org/sp/1027/Orthomiella-pontis


O. rantaizana ;Male wingshape generally straighter.
UnH with the markings poorly defined. FW markings washed out & faint. Addendum: Ground colour deep brown & markings poorly contrasted.
https://en.wikipedia.org/wiki/Orthomiella#/media/File:Orthomiella_rantaizana_20150315.jpg
https://www.flickr.com/photos/scapeview/39754383745/
http://dearlep.tw/species.html?namecode=345759&photo_id=183ff8c9e305ad90b4631b2075b96117
http://yutaka.it-n.jp/lyc4/81410001.html

Images 2 & 5 have poorer FW markings but submarginal marks are also present.


TL Seow: Cheers.

[DaveChiangMai]

Many thanks for the feedback. Glad it's not just me that finds these very confusing.

By the way, the third link for O. rantaizana is now defunct.

[Psyche]

Many thanks for the feedback. Glad it's not just me that finds these very confusing.

By the way, the third link for O. rantaizana is now defunct.


The link is fine . Just wait for the image to appear. Ignore the 'no image available' sign.


TL Seow: Cheers.

[DaveChiangMai]

Thanks. Actually it appears to be a problem with Internet Explorer only. Works fine with Chrome. Some version issues.

[Angiud]

For me all your pics are O.rantaizana.

Here O.pontis

https://live.staticflickr.com/7652/17032370777_07be1a893d_c.jpg (https://flic.kr/p/rX6mr8)

and this is O.rantaizana

https://live.staticflickr.com/4385/36798132412_e55a41c8f9_c.jpg (https://flic.kr/p/Y4J3JQ)

Simply on the field pontis is a bit larger and way paler than rantaizana :)

[Psyche]

For me all your pics are O.rantaizana.


Simply on the field pontis is a bit larger and way paler than rantaizana :)




That would mean there are a fair numbers of O. rantaizana in the Butterflies of India' website.
For the record I did a check & O. rantaizana occurs in NE India.



TL Seow: Cheers.
PS. The typical O. rantaizana rovorea that matches Yutaka' image. S. China.
https://www.inaturalist.org/observations/20274950
http://yutaka.it-n.jp/lyc4/81410001.html

[Angiud]

Here more evident, only one pontis (the paler on the left is rantaizana as well)

https://live.staticflickr.com/898/42265931822_f05406a13b_c.jpg (https://flic.kr/p/27oTX1s)

[Psyche]

I am still confused.

What are these in the Indian website?
https://www.ifoundbutterflies.org/sp/1027/Orthomiella-pontis


Evans' description of O. pontis.
Below brown with dark catenulated (chain-like) spots arranged as usual; marginal markings nearly obsolete.
UnF a spot in the cell & one in space 1b below it. UnH dorsal (inner) half, from base to discal band darkened, covering all the markings.

taxon revorea Smaller, Wings more pointed. Browner above & yellower below.


Taxon revorea ;Fruhstorfer's original description.1918.
https://archive.org/stream/tijdschriftvoore611918nede#page/55/mode/1up

I have made a translation of the underside only.

' Underside of that of pontis, deviating from the lack of a brown band on the FW, & the narrower & therefore more delicate brown patch of the HW.
Overall colour of the underside predominantly yellowish grey, instead of grey black as in pontis,& thus similar to Una usta.
Colour in Una usta.
https://www.google.com/search?q=una+usta&rlz=1C1MSIM_enMY705MY706&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiO5PzA2cXiAhXLq48KHX4uBd4Q_AUIDigB&biw=872&bih=922


The colouration described are at odds with that of Yutaka but Yutaka's images of rantaizona revorea shows the FW band nearly obsolete as described for revorea.
http://yutaka.it-n.jp/lyc4/81410001.html
http://yutaka.it-n.jp/lyc4/81420001.html


I am keeping an open mind on these for the time being.

TL Seow: Cheers.

[Psyche]

Based on Fruhstorfer's description Post 1 pic 6 is O. rantaizana revorea.
http://www.butterflycircle.com/attachment.php?attachmentid=25736

The FW is sharp; ground colour yellowish; FW band narrow/obscure; HW markings narrow.


TL Seow: Cheers.