ID requests

[Psyche]

Post 29.
The 4-line Blues are very difficult to Id from the underside alone in many species and it is likely there were many mis-identifications in the past.
The dark striae within the bands are important in the Ids.

A. Dark striae within bands strongly developed ,appearing black.
Metallic scales on HW tornal spots always strong.

A1. Nacaduba pavana.
HW marginasl spots with their inner margins level, 'flat'.
Female.
http://www.butterflycircle.com/check..._female_01.jpg

A2. Nacaduba russelli.
HW marginal spots lozenge shaped, ie. with the inner margins oval.
FW submarginal spots large.
https://thaibutterflies.com/Butterfl...duba-russelli/
Some past observations are probably this species.
These have strong dark striae & should not be N. hermus.
https://static.inaturalist.org/photo...370/large.jpeg
https://inaturalist-open-data.s3.ama...2348/large.jpg


B. Dark striae within the bands absent or rather weak.

B1. Nacaduba hermus.
Dark sriae weak, not blackish.
Metallic scales in the HW tornal spot often sparse.
HW submarginal spots 4 & 5 with rounded margins & close to the postdiscal spots/band.
Males.
https://inaturalist-open-data.s3.ama...878/large.jpeg
https://inaturalist-open-data.s3.ama...6496/large.jpg
https://inaturalist-open-data.s3.ama...1747/large.jpg
https://live.staticflickr.com/65535/...81d68726_c.jpg
Female.
https://inaturalist-open-data.s3.ama...343/large.jpeg
https://inaturalist-open-data.s3.ama...1467/large.jpg


B2. Nacaduba pactolus.
White striae buff, enhanced.
Metallic scales on tornal spot strong.
HW submarginal spot 6 quadrate & connect sharply to a narrow band formed by submarginal spots 4 & 5; Distinctive.
Male.
http://www.butterflycircle.com/check...-%20horace.jpg


B3.Nacaduba angusta.
White striae broad & spots dark.
HW spot 6 large & round.
Metallic scales in tornal spot strong.
Female - left.
http://www.butterflycircle.com/check...20khew%202.jpg


B4. Nacaduba sanaya.
No metallic scales on HW tornal spots.
FW postdiscal spots usually dislocated at vein 6.
HW postdiscal spots & submarginal spots well separated in space 4 & 5.
This species present a confusing picture as the spacing in HW space 4 & 5 varies.
Forms with the HW submarginals & postdiscals in space 4 & 5 spaced apart.(as described in the text.)
Male & female.
https://inaturalist-open-data.s3.ama...8753/large.jpg
https://inaturalist-open-data.s3.ama...4238/large.jpg
Forms in which HW submarginals & postdiscals are very close.
Male & female.
https://www.besgroup.org/wp-content/...i-LenaChow.jpg
https://inaturalist-open-data.s3.ama...5990/large.jpg

It is possible some other species are involved but without upperside pix, it is difficult to wrk this out.


B5 Nacaduba subperusia lysa.
Ssp lysa is the lowland form recorded in Singapore.
No metallic scales on HW spot
HW submarginal spots in space $ & 5 with rounded margins & always close to the postdiscal spots.
FW postdiscal band less often dislocated.
Male P. Malaysia.
https://2.bp.blogspot.com/-ToaJYf3xH...0/DSC_2628.JPG
Female Thailand.
https://thaibutterflies.com/wp-conte...subperusia.jpg


B6.Nacaduba pendleburyi
FW postdiscal band not dislocated.
HW with the submarginals & postdiscals in space 4 & 5 well separated.
Upperside with the FW black border a thread & expanded at the apex in the male (Diagnostic.)
Added: FW marginal & submarginal spots narrow, submarginal spots 4 & 5 pointed.

B7. Nacaduba solta.
FW with a very straight postdiscal band as in N. calauria
This species is not found in Singapore.



TL Seow: Cheers..

PS. It is very likely that what was thought to be one variable N. sanaya species in Singapore actually comprise two equally common species, ie. N. sanaya & subperusia..
Previous use (for comparison) of N. perusia images with only features of dark markings & unbroken postdiscal band ( from neighbourig countries ) is probably untenable.

PS 2. The two males from Thailand match the image of N. pendleburyi male in C&P4.
HW with wide spacing of postdiscals & submarginals in space 3, 4, & 5.
FW marginal & submarginal bands narrow, submarginal spots 4 & 5 pointed.
https://pamsbutterflies.com/butterfl...-sanaya-elioti

One observation looks correct for male N. pendleburyi
https://www.inaturalist.org/observations/112126841

[LJK1410]

Thank you for the detailed reply Dr Seow!

I was looking through some iNaturalist observations and this one seems a little different to me with the way the FW post-discal band curves: https://www.inaturalist.org/observations/71003020
Could it be N.pendleburyi? Of course without dorsals it is difficult to confirm.

But it matches quite closely to this observation which was IDed as N.pendleburyi, https://www.inaturalist.org/observations/117297085

[Psyche]

Post 31.

There is very little correct image of N. pendleburyi
All known shows the marginal & submarginal spots/bands to be very narrow.
While the band may be curved in pendleburyi,similar bands are also seen in sanaya & subperusia, & probably several others.
I would leave it as N. sanaya since the submarginals are large.

Two images below are definitely N. sanaya males.
If you use google zoom you can see violet at the apex.
In N. pendleburyi, it would be black.
There are examples where the postdiscal band is not dislocated; it would then be curved.
https://inaturalist-open-data.s3.ama...8753/large.jpg
https://static.inaturalist.org/photo...1909/large.jpg


TL Seow: Cheers.

[Psyche]

Nacaduba subperusia lysa.
Examples.
Cambodia.
https://geenature.com/taxa/animalia/...ubperusia-lysa
Thailand.
https://thaibutterflies.com/Butterfl...uba-superusia/
P. Malaysia.
https://3.bp.blogspot.com/-CCzm1ZlQs...rusia+lysa.jpg
http://nlliew66butterflies.blogspot....uhstorfer.html
Singapore.
https://www.inaturalist.org/observations/154051306
https://www.inaturalist.org/observations/138368856

N. sanaya.
The key indicates that the space between the submarginal & postdiscal spots in HW spaces 4 & 5 should be at least half the width of the postdiscal band.
This will only allow those in which the submarginals & postdiscals are almost touching to be excluded.
The FW submarginal spots have mostly convex margins in subperusia & straight margins in sanaya.
These examples are probably N. sanaya.
https://www.besgroup.org/wp-content/...i-LenaChow.jpg
https://www.inaturalist.org/observations/147389511
https://inaturalist-open-data.s3.ama...5068/large.jpg
https://inaturalist-open-data.s3.ama...3/original.jpg
https://inaturalist-open-data.s3.ama...3843/large.jpg
This one seem close enough to suggest N. subperusia.
The postdiscal band can not be used to confirm an ID.
https://inaturalist-open-data.s3.ama...6886/large.jpg

Some shots with narrow FW peripheral bands & wide HW spacing suggest. N. pendleburyi
https://www.inaturalist.org/observations/23644499
https://www.inaturalist.org/observations/112126841

TL Seow; Cheers.

[LJK1410]

Quite a few of my previously IDed N. sanaya females have the HW post-discal band close to the submarginal band,

These I'm still fairly confident is still N.sanaya since the HW submarginals are not strongly convex:
https://www.inaturalist.org/observations/128760828
https://www.inaturalist.org/observations/137955412

This was the one you pointed out above, but would the HW submarginals be considered convex?
https://www.inaturalist.org/observations/145646317

This one has more convex submarginals and the HW post-discal and submarginal bands are close together, possible for N.subperusia lysa? No better/closer shots unfortunately.
https://www.inaturalist.org/observations/124359422


This observation of a female from Cambodia clearly showing the convex HW submarginals:
https://www.inaturalist.org/observations/42730361

[Psyche]

Post 34.

1. This is a male & the HW spacing is quite wide. No issue.
https://www.inaturalist.org/observations/128760828

2. This have the HW submarginals with straighter margin so suggest N. sanaya.
https://www.inaturalist.org/observations/137955412

3. This has the HW spacing even closer, HW submarginal spots variable.
If this is given to someone new, he would IDed as subperusia by the key.
You can only convinced him by netting a specimen for examination to confirm it.
https://www.inaturalist.org/observations/145646317
http://yutaka.it-n.jp/lyc4/81210010.html

4. This appears to be N. hermus.
https://www.inaturalist.org/observations/124359422
A better pic showing the metallic scales.
https://www.inaturalist.org/observations/149097939


Typical N. sanaya females.
Wallace Collection
https://wallace.biodiversity.online/...doptera-000059
Bred by Horace.
https://www.butterflycircle.com/chec...race%20tan.jpg
Panti Forest, Johor.
https://www.flickr.com/photos/gancw1/14350846826


TL Seow: Cheers.

[LJK1410]

Hi Dr Seow,

I got some Arhopalas that I'm not too sure about. I know this group is really difficult for a definitive ID but any pointers would be much appreciated!

1. Arhopala athada? Thought the HW spots 6 & 7 seem quite different from a typical A.athada. Could it be something else? Shot at Upper Seletar Reservoir.
https://www.inaturalist.org/observations/172636328
photo1696144999 (1).jpeg

2. Arhopala sublustris? I recall the size was smaller than A.athada. Shot at Bukit Timah Nature Reserve.
https://www.inaturalist.org/observations/177311767
photo1696144999.jpeg
WhatsApp Image 2023-10-01 at 7.22.42 PM.jpeg

3. alea subgroup. This one was shot in Panti Forest, Johor, Malaysia.
https://www.inaturalist.org/observations/175865453
photo1696163676.jpeg
WhatsApp Image 2023-10-01 at 7.35.53 PM.jpeg

4. Another alea subgroup from Panti Forest, but no upperside shots.
https://www.inaturalist.org/observations/175865588
photo1696163689.jpeg