Request for ID

[Samuel T]

Dr Seow, need your guidance to ID this butterfly. Taken at Upper Seletar Reservoir. Thanks.

Regards
Samuel

[atronox]

Male Nacaduba beroe neon, from the absence of the lowermost costal spot on the forewing

[Psyche]

Agreed it is male Nacaduba beroe neon here.
A word of caution on relying on just one features for ID.
In Singapore where there are only small separated colonies of species any crossing between closely related species may result in an abnormal feature in the colony far longer or more permanent.
Where the colony is large an inherited feature from a cross will overtime be diluted & may died out.


The features of the male Nacaduba beroe neon (not applicable to the female).
1. Dark striae or lines within the bands obsolete or weak.
2. Lowest FW costal spot absent.
3. Wingbases darkened variably.
4. Upperside deeper violet blue without a frosted appearance.
Typical males Singapore.
https://wanderingbutterflyeffect.fil...f39fce860b.jpg
http://1.bp.blogspot.com/-xhPzgiOQMi...-Line-Blue.jpg
http://www.butterflycircle.com/check...imon%20Sng.jpg
Typical N. beroe ,Malaya.
http://1.bp.blogspot.com/-et_aVVQw8e...0/DSC_0015.JPG
http://4.bp.blogspot.com/-yS0EBTwvFo...0/DSC_0105.JPG
http://farm7.static.flickr.com/6186/...62cac367_b.jpg


The features of the msle Nacaduba berenice icena .
1. Dark striae/lines within the bands strongly developed.
2. Lowest FW costal spot present.
3. Wingbases not darkened.
4. Upperside a frosted lavender blue.
http://www.butterflycircle.com/check...drick%20Ho.jpg
http://www.butterflycircle.com/check...hee%20Beng.jpg
http://www.butterflycircle.com/check...obby%20Mun.jpg


Considered this shot of a male taken by Federick ,Lornie Trail, 2014,
http://3.bp.blogspot.com/-m0mSgms7_-...a+berenice.jpg
http://2.bp.blogspot.com/-2z1tHnAAtb...8male%2529.jpg

The underside have the black striae strongly developed but the lowest costal spot is missing.
The upperside is a frosted lavender blue of N. berenice.

The frosted blue appearance is due to the presence of long white ribbon scales (present only in the male berenice & sex-determined).

Thus this male is definitely N. berenice icena .
It may have a hybrid element or just that occasionally in berenice the lowest costal spot is absent.


TL Seow: Cheers.

[Samuel T]

Thanks Aaron 😀

[Samuel T]

Thanks Dr Seow 😀

[atronox]

Yes, Federick's shot does look exceptional