Arctornis in Singapore.

[Psyche]

After more than a decade there is still no further studies of the Arctornis in Singapore.
MoB remains the sole reference.
The white species are very difficult.
However a few which can be identified can be eliminated from the unidentified list.

Arctornis singaporensis.
White, without corrugated scalings.
No black discal spot.
Veins green tinged.
Male ground whiter & the veins stripes less defined.
Female vein stripes enhanced by interneural bands of white scales,
The two sexes can look like different species.
Males.
https://static.inaturalist.org/photo...706/large.jpeg
https://inaturalist-open-data.s3.ama...3155/large.jpg
https://inaturalist-open-data.s3.ama...586/large.jpeg
Females.
https://inaturalist-open-data.s3.ama...366/large.jpeg
https://inaturalist-open-data.s3.ama...3/original.jpg
Pair.
https://www.inaturalist.org/observations/105780706


Arctornis marginalis.
This rather rare as there is only one shot.Veins tinged green; grey triangles at distal margins.
Apical costa dark edged.
Singapore.
https://www.inaturalist.org/observations/82994882
P. Malaysia. Male & female.
https://www.inaturalist.org/observations/35231033
https://www.inaturalist.org/observations/19966353

[Psyche]

Collonette in 1932 wrote onthe Arctornis in Malaya (including Singapore).
The white species recorded in Singapore includes A. nivosa, singaporensis, phrika, riguata, perfecta, camirusquama & marginalis.



A 2019 survey of the Bukit Timah Forest include a new record, A. ungula.
A. ungula is described as " frons with three black spots & two lower ones. legs spotted.
https://www.mothsofborneo.com/part-5...thini_1_40.php
Probable A. ungula.
Sabah.
https://inaturalist-open-data.s3.ama...491/large.jpeg
P. Malaysia.
https://inaturalist-open-data.s3.ama...0195/large.jpg

[Psyche]

Three species recorded in the past in Singapore are probably extinct.

1. Arctornis perfecta.
Large species with deep & acute FW in the male.
No discal spot; satiny white without corrugation.
https://www.mothsofborneo.com/part-5...thini_1_36.php
P.Malaysia.
https://static.inaturalist.org/photo...7015/large.jpg



2. Arctornis phrika.
FW with a discal spot & a sinuous postmedial fascia.
Frons & palps dull rufous brown & legs patched the same.
https://www.mothsofborneo.com/part-5...thini_1_26.php
Fortunately there is a BOLD image with visible patterns.
http://v3.boldsystems.org/pics/EPNG/...1479336568.JPG
Sabah.
https://inaturalist-open-data.s3.ama...135/large.jpeg
P. Malaysia.
https://inaturalist-open-data.s3.ama...7577/large.jpg
https://inaturalist-open-data.s3.ama...9/original.jpg
https://inaturalist-open-data.s3.ama...5808/large.jpg

There is much confusion with Arctornis poecilonipha in the past.
The general description seem to fit both.
https://www.mothsofborneo.com/part-5...thini_1_21.php

Arctornis poecilonipha.
FW with a rather larger irregular discal spot.
Frons with a dark brown patch & palps much paler; legs marked with dark brown.
FW more densely laid with opalescent scales, postmedial angled at 90% to costa at upper third.
P. Malaysia.
https://inaturalist-open-data.s3.ama...9230/large.jpg
https://inaturalist-open-data.s3.ama...8089/large.jpg
https://static.inaturalist.org/photo...2218/large.jpg
https://inaturalist-open-data.s3.ama...0203/large.jpg



3. Arctornis camurisquama.
A distinctive white arcuate postmedial band that falls short of costa & dorsum. Costa more reflective.
https://www.mothsofborneo.com/part-5...thini_1_50.php
Sabah.
https://inaturalist-open-data.s3.ama...695/large.jpeg

[Psyche]

Following are attempts at ID.
There are far fewer species in Singapore & the majorities are likely to be widespread species.


Arctonis nivosa. Mainland Asia.
This is recorded from Singapore.
Collinette state of this species , diaphanous like A. singaporensis, but creamy white, denser scaling & lacks the green veins.
One specimen match this well.
Bukit Panjang Sep 2020.
https://inaturalist-open-data.s3.ama...494/large.jpeg


Arctornis semihyalina. Sundaland to PNG.
Translucent without dense patches; fine transverse strations in fresh specimen; Frons brown . Palps & foreleg paler brown.Discal spot present.
https://www.mothsofborneo.com/part-5...thini_1_24.php
June 2022 MacRitchie Reservoir.
https://static.inaturalist.org/photo...3592/large.jpg
Jan 2022 Yishan
https://inaturalist-open-data.s3.ama...0115/large.jpg
Aug. 2021 Yio Chu Kang.
https://inaturalist-open-data.s3.ama...3484/large.jpg
Feb. 2020 Yishan.
https://inaturalist-open-data.s3.ama...0728/large.jpg

There are some which do not show much striations although fresh. ? Probable variant.
https://inaturalist-open-data.s3.ama...454/large.jpeg

Wear quickly destroy the patterns in sparsely scaled species.
Worn specimens.
https://inaturalist-open-data.s3.ama...328/large.jpeg
https://inaturalist-open-data.s3.ama...1714/large.jpg
https://inaturalist-open-data.s3.ama...3001/large.jpg
Male with less rounded FW.
https://inaturalist-open-data.s3.ama...429/large.jpeg

[Psyche]

Arctornis riguata.

This have a weak discal spot; irregularly oriented scales on the FW.
Diagnostically there are deep faint grey triangle on the distal margin.
The apical costa is darken, causing confusion with A. marginalis.
https://www.mothsofborneo.com/part-5...thini_1_22.php

A serious outbreak occur in Probolinggo Java in 2011.
Initally it was identified as A. submarginata.
The 2013 article indicate it is largely Arctornis riguata.
https://data03.123doks.com/thumbv2/1...-berwarna.webp
https://www.sciencedirect.com/scienc...78301916301024

Dec. 2014 Toh Yi Drive.
https://inaturalist-open-data.s3.ama...5457/large.jpg
Jul.2021 Thomson Lane.
https://inaturalist-open-data.s3.ama...123/large.jpeg
Jun. 2022 Sengkang.
https://inaturalist-open-data.s3.ama...3053/large.jpg

[Psyche]

Likely Arctornis rufimarginata.
https://www.mothsofborneo.com/part-5...thini_1_57.php
Wings are uniform white (ie without corrugation or rippled scales).
Fringe & costa golden-brown. Swinhoe states rufous (reddish)
The colour is rendered too grey causing the brown to appear blackish.
Jan. 2019 CWC.
https://inaturalist-open-data.s3.ama...799/large.jpeg


Possibly Arctornis hedleyi.. Prominent FW marginal grey 'triangles'.
https://www.mothsofborneo.com/part-5...thini_1_71.php
Dec. 2021 USR.
https://inaturalist-open-data.s3.ama...542/large.jpeg

[Psyche]

Probable Arctornis perfecta.
The only satiny white species here with an acute FW (male) & lack a discal spot.
Uniform white without corrugation or condensed scales.
https://www.mothsofborneo.com/part-5...thini_1_36.php
https://inaturalist-open-data.s3.ama...676/large.jpeg
The 2nd pic shows with a deeper brown patch besides each eye(whitish) & the palps shaded dark brown ventrally.
The brown bar across the base of the antennae is not visible here.
https://inaturalist-open-data.s3.ama...694/large.jpeg

Other similar species have a black discal spot.
UnIDed species.
Fron is marked as described for A. submarginata but wingshape is incorrect.
https://inaturalist-open-data.s3.ama...8487/large.jpg

[Psyche]

Probable Arctornis rhopica.
Some resemblance to A. poecilonipha.
Frons , palps rufous brown.
Jan 2020 Mandai Road.
https://inaturalist-open-data.s3.ama.../original.jpeg
https://inaturalist-open-data.s3.ama.../original.jpeg
https://inaturalist-open-data.s3.ama...9024/large.jpg
https://www.mothsofborneo.com/part-5...thini_1_34.php

For comparison. P. Malaysia.
Probable A. rhopica.
https://inaturalist-open-data.s3.ama...4650/large.jpg
A. poecilonipha.
https://static.inaturalist.org/photo...7098/large.jpg

[Zicky]

Dear Doctor Seow,

Would then this observation be faded female Arctornis singaporensis?
I do not understand the part where scale structure can be corrugated, but this observation is white, veins are green and lacks a discal spot
Inat link - https://www.inaturalist.org/observations/142270783

Skipping regards
Zicky

[Psyche]

Dear Doctor Seow,

Would then this observation be faded female Arctornis singaporensis?
I do not understand the part where scale structure can be corrugated, but this observation is white, veins are green and lacks a discal spot
Inat link - https://www.inaturalist.org/observations/142270783

Skipping regards
Zicky

Yes.
A. singaporensis; No discal spot; no corrugation, green veins ;vein-stripes enhanced in the female.


Corrugation : formings ridges , like roof tiles.
ARCTONIS.png