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Psyche
23-May-2024, 08:22 PM
The alea subgroup can be extremely frustrating to ID.

The cleander group.
28533
FW spot 4 can sometimes be slightly shifted out causing confusion .
Similarly HW spot 7 is sometimes shifted or overhang a little inwards of spot 6.

The cleander subgroup consist of two species , athada & silhetensis.
They are very large about 2X the size of the alea subgroup.
The larger wings mean the HW postdiscal spots & the submarginal spots/band are widely separated.

Five members of the alea subgroup were recorded in Singapore.
They are A. milleri, sublustris, normani, phanda & aroa.

Two are probably extinct.

Arhopala aroa.
Wings are rather elongate with rounded margins. This cause the markings to be well-spaced.
The upperside is darkish blue.
UnH spot 6 is tapered downward sharply so that it is almost triangular.
https://yutaka.it-n.jp/lyc4f/82180001.html
Sunny Chir posted a montage of four individuals for comparison a dacade ago, one of which resembles A. aroa in the HW spot 6.
It would certainly be interesting to check that image again.

Arhopala phanda.
Upperside is darkish blue.
The underside have the markings broad.
UnH spots 6 & 7 are quadrate & joined like a column.
https://m.singapore.biodiversity.online/species/A-Arth-Hexa-Lepidoptera-000442
These two males should be A. phanda , wrongly labelled.
https://m.singapore.biodiversity.online/species/A-Arth-Hexa-Lepidoptera-000492


The three extant species are A. milleri, sublustris & normani.
They are very similar on hte underside.

A sublustris is by far the commonest species.
The upperside blue in the male is more shiny & reflective than all other species.
UnH spot 6 tapers from top downwards & may be more convex on the outer margin.
Using a flash should show its reflective quality.
These below are confirmed by the shiny blue uppersides.
https://www.inaturalist.org/observations/197700376
https://www.inaturalist.org/observations/189834021
https://www.inaturalist.org/observations/213668206
https://www.inaturalist.org/observations/86284346
https://www.inaturalist.org/observations/86168391
https://www.inaturalist.org/observations/86165404
https://m.singapore.biodiversity.online/species/A-Arth-Hexa-Lepidoptera-000443
Males with a bit of brighter blue exposed on the HW.
https://www.inaturalist.org/observations/218058796
https://www.inaturalist.org/observations/218058787
https://www.inaturalist.org/observations/218058785
https://www.inaturalist.org/observations/218058780
https://www.inaturalist.org/observations/218058779



A. milleri.
Male upperside is a less reflective indigo blue.
It appears dark blue in a shot.
UnH spot 6 also tapers downwards as in A. sublustris.
It seem impossible to separate two based on the underside alone.
Male.
Note in the middle pic especially the HW upperside is very dark, even with flash.
https://www.inaturalist.org/observations/213668173
From Selangor. Note dark blue upperside.
https://www.inaturalist.org/observations/168799932
Female .The upperisde matches Otsuka Lycaenids of Borneo L207 (Free pdf available.)Note long palpi.
https://www.inaturalist.org/observations/189320986



A. normani.
Male upperside deep violet blue appearing darker than in sublustris.
UnH spot 6 with sides hardly tapers, almost parallel, usually well overlapping the cellend bar.
https://m.singapore.biodiversity.online/species/A-Arth-Hexa-Lepidoptera-000439

Probable A. normani.
Note shape of HW spot 6.
The little bit of FW blue in the FW tear looks dark despite the flash.
https://www.inaturalist.org/observations/214584068
Added.
Probable A. normani. Note UpH very dark blue, HW spot 6 with parallel sides.
https://www.inaturalist.org/observations/218058801


Finally .
Arhopala agrata.
This resembles an alea subgroup member.
This is the only tailed Arhopala here with FW spot 9 absent or nearly obsolete.
HW spot 6 is much wider than spot 7 & the markings tend to be weak.
Federick HO & Sunny Chir shot this male in the CCA in 2010.
Should still be extant in the protected forest.
https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiyCfW0amTGW35865DjpZsAA0ke5KEEF5VK6NpIkzEgna jkPEondIJ2mgzxM-BRdnEcGKS5oc8CHfNsUOtROZVinvW_YrA27mPVV8xOa2ZaKy8H dwHX27_Lu0ZlI6ay748iWhUDK17iGugh/s1600/DSC7123-Arhopala.jpg
https://peacockroyal.blogspot.com/2010/11/deep-inside-cca.html


TL Seow: Cheers.