31 May 2023

Butterfly of the Month - May 2023

Butterfly of the Month - May 2023
The Ciliate Blue (Anthene emolus goberus)

A Ciliate Blue feeding on a damp wooden log

Time flies, and the month of May is almost over as we head for June and towards the end of the first half of 2023. The month of May belongs to the astrological sign Taurus. For those born between 20 April and 20 May, your zodiac sign is Taurus. We featured Capricorn, Aquarius, Pisces and Aries in the preceding Butterfly of the Month blogposts and will now move into the next in the series. The 12 zodiac signs are Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius, and Pisces.

A Ciliate Blue feeding on the flower of Prickly Lantana (Lantana camara)

Taurus (♉︎) (Ancient Greek: Ταῦρος, romanized: Taûros, Latin for "bull") is the second astrological sign in the modern zodiac. The sign of Taurus is associated with several myths and bull worship from several ancient pagan cultures. It was established among the Mesopotamians, who called it "The Great Bull of Heaven,"

A Ciliate Blue feeding on the flower of the Bandicoot Berry (Leea indica)

Taureans are typically calm, patient, and kind. Adopting the characteristics of their zodiac symbol, the bull, they will start seeing red and keep charging on once they focus on an objective. They will be difficult to calm once provoked. They have a persistence and patience to see things through to their logical conclusions. Taureans can tend towards obstinacy in their outlook and their minds will be hard to change once they adopt a position.

Habits are a prominent theme for those born under the sign of the Bull, as their routines can help them be productive and organized. But when the habit has outlived its usefulness, they may stick to it long after it is necessary. A negative trait of a Taurean is that of being averse to change, and overly rooted in their ways and mindset. Though not particularly vengeful, Taurus' long memory may mean they seldom forget a slight or mistake, and it may take offenders a long time to earn back the Bull's trust, or to forgive someone who has betrayed them.

Our feature butterfly for the month of May 2023 is the common Ciliate Blue (Anthene emolus goberus). A small Lycaenid, this species has a wide distribution across Singapore, and exists in habitats ranging from urban greenery to mangrove areas, nature parks and the forested nature reserves. It is a fast-flying species, sometimes engaging in dogfights with another individual of the same species.

Upperside and Underside of Male and Female Ciliate Blue.  Animation by Horace Tan

The upperside of the male Ciliate Blue is a deep purple blue whilst the females are generally dull brown with light blue wing bases. There are dark marginal spots at the tornal area of the hindwing. The underside is a pale greyish brown with a series of white striations on both wings. There is a large orange-crowned black marginal spot on the hindwing. A prominent black spot on the dorsum on the underside of the hindwing is a key characteristic of this species.

There are two species from the genus Anthene in Singapore. Both species are characterised by short fine tails which are extensions of the hindwing cilia. The other species, The Pointed Ciliate Blue, is the rarer of the two species found in Singapore, but both may frequent the same localities. The Ciliate Blue has solid jet-black eyes and the antennae are banded.

A Ciliate Blue puddling at a damp sandy path

Males of the species are sometimes found puddling on damp footpaths. An interesting behaviour of the species is that it is partial to human perspiration, and sometimes stays on a person for long periods of time, and keeps coming back to feed on the perspiration despite being chased away!

A Ciliate Blue laying eggs on the stem of its host plant. Note the cluster of green eggs and the Weaver Ant all ready to "farm" the caterpillars

The Ciliate Blue's caterpillars feed on a variety of host plants and can usually be found on Saraca thaipingensis (Yellow Saraca), Saraca indica (Ashoka Tree), Bauhinia sp., Smilax setosa (Sarsaparilla Vine), Senna fistula (Fabaceae, common name: Golden Shower), Senna alata (Seven Golden Candlesticks), Syzygium zeylanicum (Spicate Eugenia). Eggs are usually laid in clusters and the caterpillars are tended by Weaver Ants.

Text by Khew SK : Photos by : Gavin Chan, Khew SK, Ann Kong, Loh MY, Tan King How, Michael Soh, Horace Tan and Mark Wong

14 May 2023

Life History of the Flash Royal

Life History of the Flash Royal (Tajuria deudorix ingeni)

Butterfly Biodata:
Genus: Tajuria Moore, 1881
Species: deudorix Hewitson, 1869
Subspecies: ingeni Corbet, 1948
Wingspan of Adult Butterfly: 28-34mm
Caterpillar Local Host Plants: Dendropthoe pentandra (Loranthaceae, common name: Malayan Mistletoe), Scurrula ferruginea (Loranthaceae, common name: Rusty-leafed Mistletoe).

Physical Description of Adult Butterfly:
On the upperside, the male is shining blue with black distal borders on both forewing and hindwing; the female is pale purplish blue with black borders. On the forewing, the black border in the female is narrower, reaching near cell apex. The forewing dorsal area is whitened. On the underside, both sexes are dark yellowish brown with a postdiscal series of dark brown striae on both wings. The post-discal line is closer to the termen than to the cell end. In the hindwing, black tornal spots are present in spaces 1a and 2. Adjacent to these spots, prominent orange patches extend towards the postdiscal line, and upwards into spaces 3 and 4. Each hindwing has a pair of white-tipped black tails at end of veins 1b and 2.

Upperside view of a male Flash Royal.

Underside view of a male Flash Royal.

Upperside view of a female Flash Royal.

Underside view of a female Flash Royal.

A rear-end view of a Flash Royal, showing the orange-crowned block spot in the tornal lobes.

Field Observations:
The Flash Royal was recorded as extant in Singapore by early researchers and its life history was documented during WWII in Singapore by F.C, van Ingen while he was a prisoner of war. Due to its close resemblance to the much commoner Felder's Royal (Tajuria mantra), its sightings in the past few decades in Singapore had largely been overlooked or wrongly identified. A recent review of local photographic records of Felder's Royal by Dr Seow Tek Lin revealed that several of them are actually Flash Royal, thus allowing us to confirm the existence status of this species. It is noteworthy that sightings of the Flash Royal in the past three decades have all been confined to the Southern Ridges.

An archived picture of the Flash Royal taken in 2006 but misidentified as Felder's Royal then.

On the upperside, there are two main differences between the Flash Royal and the Felder's Royal. 1. The male Felder's Royal is greenish blue and the female is greyish blue, whereas both sexes of the Flash Royal are purer blue; 2. The dorsal area of the forewing is whitened in the Flash Royal, but not whitened in the Felder's Royal. On the underside, the differences are more subtle and mainly occur in the hindwing. 1. the parts of the postdiscal line in spaces 2 and 3 are straighter in the Flash Royal, but more curved in lower portion in the Felder's Royal; 2. the part of the postdiscal line in space 1b resembling a chevron is more rounded in the Flash Royal, but more pointed in the Felder's Royal. 3. The marginal patch in space 1b is bluish green dotted with black in the Felder's Royal, but whitish dotted with black in the Flash Royal.

Comparison of hindwing underside features between females of Tajuria deudorix and Tajuria mantra.

Comparison of hindwing underside features between males of Tajuria deudorix and Tajuria mantra.

Early Stages:
In Singapore, thus far two larval host plants have been confirmed, namely, the Malayan Mistletoe (Dendropthoe pentandra) and the Rusty-leafed Mistletoe (Scurrula ferruginea). On the larval host plant, the early stages of the Flash Royal feed on the leaves and flower buds. In all but the final instar, the caterpillar has the habit of grazing on the leaf surface, creating long grooves in the process.

Local host plant #1: Dendropthoe pentandra (Malayan Mistletoe).

Local host plant #2: Scurrula ferruginea (Rusty-leafed Mistletoe)

Eggs are laid singly on the stem or leaf of the host plant. Each egg is about 1mm in diameter and about 0.5mm in height. It is white with a slight greenish tinge when freshly laid. The bun-shaped egg has a depressed micropylar at the pole and a surface reticulated with polygonal depressions.

A Flash Royal laying an egg on a stem of the Malayan Mistletoe.

Two views of an egg of the Flash Royal.

A sequence of views from left to right, showing the egg shell being eaten away to allow for the emergence of the caterpillar. The rightmost view shows the empty egg shell.

It takes about 4.5-5 days for the egg to hatch. The young caterpillar consumes just enough of the egg shell to emerge. The remnant of the egg shell is left alone after the caterpillar emerges from it. The newly hatched is pale pinkish brown with reddish lateral bands and posterior patches, and has a length of about 1.6mm. Long setae (hairs) run along the length of the body dorsally as well as sub-spiracularly. Raised dorsal tubercles are transparent. The body also features a diamond-shaped pale brown prothoracic shield and a pale brown anal plate. As it grows in this instar, the body ground colour turns yellowish brown, and a dorsal reddish band gains prominence gradually. The 1st instar lasts about 5 days with the body length increased to about 3.6mm.

A newly hatched caterpillar next to its empty egg shell.

Two views of a newly hatched caterpillar, length: 1.6mm.

Two views of a L1 caterpillar, length: 3.1mm.

A 1st instar caterpillar with its grazing trail on the leaf surface.

A late 1st instar caterpillar of the Flash Royal, dormant prior to the moult to the next instar.

In the 2nd instar caterpillar, long dorsal setae seen in the 1st instar are now absent. The body is pale yellowish brown and adorned with a prominent dorsal red band stretching from the mesothorax to the 7th abdominal segment. The reddish band forks into two from the mesothorax to the prothorax. At the posterior end, the reddish band broadens from the 7th abdominal segment into a reddish patch covering the carapace feature over the fused 8th-10th segments. The prothoracic shield is brown in colour and the dorsal nectary organ on the 7th abdominal segment is now distinguishable. Small and irregular-shaped reddish patches are scattered throughout the body surface. As it feeds and grows in this instar, the body takes on a greenish undertone. The 2nd instar lasts for about 5 days, with the body length reaching up to 6mm.

A newly moulted 2nd instar caterpillar of the Flash Royal, eating its old skin (exuvia).

Two views of a 2nd instar caterpillar of the Flash Royal, early in this instar, length: 2.5mm.

A 2nd instar caterpillar of the Flash Royal feeding on flower buds of the Malayan Mistletoe.

Two views of 2nd instar caterpillar of the Flash Royal, late in this instar, length:4.6mm.

Two views of a 2nd instar caterpillar, dormant prior to its moult.

Initially, the 3rd instar caterpillar resemble the 2nd instar mostly, but with a greenish body and narrower reddish dorsal band, and up to only six sub-spiracular reddish patches. Some individual will still have some degree of forking of the reddish band on the mesothorax, but the forked arms will gradually disappear as it grows in this instar. On the other hand, a reddish band branches around the prothoracic shield and stretch to the anterior end of the prothorax. The dorsal nectary organ on the 7th abdominal segment and the tentacular organs on the 8th abdominal segment are now easily discernible. The body reaches up to 12-13mm in the 3rd instar. After about 5 days in the 3rd instar, the moult to the 4th instar takes place.

Two views of a newly moulted 3rd instar caterpillar feeding on its exuvia.

Two views of a 3rd instar caterpillar feeding on flower buds of the Malayan Mistletoe.

A 3rd instar caterpillar feeding on a leaf of the Rusty-leafed Mistletoe.

A late 3rd instar caterpillar, dormant prior to the next moult, length: 12.5mm.

The 4th instar caterpillar resembles the 3rd instar caterpillar closely but with much narrower and discontinuous reddish dorsal band. In general there are still six reddish sub-spiracular patches, but some of these could be missing in some individuals. In this instar, the caterpillar switches to the habit of eating along the leaf edge and rarely grazes on the leaf surface. The 4th (and final) instar lasts about 6-7 days with the body length reaching up to 20-22mm.

Two views of a newly moulted 4th instar caterpillar, eating its exuvia.

Two views of a 4th instar caterpillar of the Flash Royal feeding along the leaf edge of the Malayan Mistletoe.

Two views of a 4th instar caterpillar on a leaf of the Malayan Mistletoe, length: 19mm.

As the 4th instar comes to an end, the anterior segments to the 4th abdominal segment, and the posterior segments starting the 7th abdominal segments gradually turn pale yellowish brown while the portion in between remains greenish. Soon after, the caterpillar ceases its feeding activity and its body gradually shrinks in length. The pre-pupatory caterpillar wanders around for a suitable pupation site. Typically it settles for a spot on the leaf surface of the host plant. At the chosen pupation site, it stays dormant for about 0.5 day or so before spinning a silk pad to which it attaches itself via claspers at the posterior end.

Two views of a late 4th instar caterpillar of the Flash Royal, with an ant in attendance at its dorsal nectary organ.

Two views of a late 4th instar caterpillar on Rusty-leafed Mistletoe, still feeding.

Two views of another late 4th instar caterpillar of the Flash Royal. Feeding has ceased.

Two views of a pre-pupa of the Flash Royal on the upperside of a leaf of the host plant.

About one day after the pre-pupatory caterpillar secures itself to the pupation site, pupation takes place. The pupa is held firmly via a broad cremastral attachment to the silk pad. It is 13.8 to 14mm in length, with the typical shape for a lycaenid pupa. It is mostly greenish in the thorax, wing pads and the lower part of the abdomen, reddish brown in the mesothorax and metathorax, and the dorsum of the abdomen in the middle and the posterior segment. Two short and yellowish cephalic horns are also present.

Video: A Flash Royal caterpillar turns into a pupa.

Two views of a pupa of the Flash Royal, length: 13.8mm.

Fully developed pupa. Top: male; bottom: female. Here the difference in the bluish patch in the wing pad is evident.

Eight days later, the pupa becomes darkened in color signaling the imminent emergence of the adult. The next day the adult butterfly emerges from the mature pupa (pupal period:9 days).

Video: A female Flash Royal emerges from its pupal case.

A newly eclosed male Flash Royal resting near to its pupal case.

  • [C&P5] The Butterflies of The Malay Peninsula, A.S. Corbet and H.M. Pendlebury, G. and N. van der Poorten (Eds.), 5th Edition, Malayan Nature Society, 2020.
  • Butterflies of Thailand, Pisuth Ek-Amnuay, 2nd Edition, 2012.
  • A Field Guide to the Butterflies of Singapore, Khew S.K., Ink On Paper Communications, 2nd Edition, 2015.
  • Tajuria deudorix ingeni. Extant in Singapore?, Seow T.L., ButterflyCircle Forum thread, 29-Jun-2014.
Text by Horace Tan, Photos by Loh Mei Yee, Khew SK and Horace Tan, Videos by Loh Mei Yee and Horace Tan.