Gerosis tristis or G. limax

[DaveChiangMai]

I photographed this on 28 Jun 24 at Ton Nga Chang WS in southern Thailand. To me this is one of the Gerosis species, and it strongly resembles the image of Gerosis tristis tristis in Kimura (size, shape and positioning of spots in FW).
I am aware this is a rare and poorly known species. The only alternative I feel would be Gerosis limax, but none of the images I have or that I find in the literature match well.
I'd be interested in opinions on the ID as Gerosis tristis tristis.
Many thanks.

28544

[Psyche]

Agreed, this is Gerosis tristis tristis.Male.
There seem no image on the web.

I do have images of the male from C&P4 (BMP) & Fleming (Butterflies of west Malaysia & Singapore.

This the only male in which the HW white band is much sullied with the veins dark-dusted.


The male of G. limax have a clearer Hw white band.
More importantly the FW hyaline spot at the cellend typically runs the width of the cell.
https://singapore.biodiversity.online/species/A-Arth-Hexa-Lepidoptera-000064
https://yutaka.it-n.jp/hes/90810010.html

The female of G. tristis have a white HW band & would look similar to that sex of G. limax & phisara but the abdomen is mostly mostly white.


TL Seow: Cheers.

[Psyche]

I did locate a pic of the female Gerosis tristis.

This pic was taken in Singapore twenty years ago.
It was thought to be G.sinica.
https://www.butterflycircle.com/attachment.php?attachmentid=119&stc=1&d=1088336228
Like sinica it has the abdomen with a white band, but the FW spots do not extend down to the lower margin, joining the HW band.

TL Seow: Cheers.

[DaveChiangMai]

Many thanks for the confirmation and details.