26 April 2020

It Takes Two! : Part 2

It Takes Two! : Part 2
a.k.a. Butterfly Sex!

A mating pair of Common Posy resting on a leaf 

In this 2nd part of the series featuring mating butterflies, we investigate the diversity of mating species amongst the remaining three families of butterflies - Riodinidae, Lycaenidae and Hesperiidae. Unlike the larger butterfly species in the previous week's blogpost, the species of these 3 families of butterflies are much smaller in size and it takes a bit of luck, opportunity and patience on the part of the butterfly photographer to shoot these mating pairs.

A mating pair of Pale Mottle with the larger female on the right

It is difficult to establish with certainty, whether the males or females of these mating pairs do the flying in the field. In our observations as recorded in the families with larger butterflies or slow flyers, we could study them as they move from perch to perch. These smaller species in the remaining three families prove slightly more challenging to follow when they are in flight.

A mating pair of Large Snow Flat, with their wings opened flat

The mating pairs of these smaller butterflies are generally more skittish, and are able to fly quite rapidly out of reach, if disturbed. Some move under leaves to hide, whilst others fly to treetop levels to get out of harm's way. However, if approached stealthily, a photographer may be able to capture a good shot of the mating pair that are undisturbed and stay still.

Family : Riodinidae

A mating pair of the Spotted Judy at Mt Faber Park

There are only 5 species in this family that are extant in Singapore. Most are relatively uncommon and at least one species, the Harlequin, is critically endangered as its local habitat where a small colony is found in, is in danger of being wiped out by development. All the other species are shy and prefer heavily shaded habitats and forested areas.

A mating pair of the Malayan Plum Judy with the male on the right

Observations of mating pairs of the Riodinidae are rare and we have on record, only the Malayan Plum Judy and Spotted Judy. They are still quite skittish even when mated and are easily spooked off when disturbed. It is difficult to say for sure whether the male or female does the flying for the pair as there have been few observation records of mating pairs.

Family : Lycaenidae Subfamilies : Curetinae, Poritiinae, Miletinae and Aphnaeinae

Mating pairs of Malayan Sunbeam (top) and Sumatran Sunbeam (bottom)

Collectively, these four subfamilies of the family Lycaenidae support a total of 13 extant species in Singapore. Of the Curetinae (or Sunbeams), there are only 2 species found here, we have had records of mating pairs of both. Both species, the Malayan Sunbeam and Sumatran Sunbeam, are moderately common with a wide distribution all over Singapore in their preferred habitats.

Mating pair of Sumatran Gem

The Sumatran Gem is the only representative of the subfamily Poritiinae which we have recorded a mating pair. Both the local species are rare and very local in distribution, preferring the heavily shaded forest understorey in the nature reserves of Singapore.

Mating pairs of the Pale Mottle (top) and Lesser Darkwing (bottom)

Amongst the seven species from the subfamily Miletinae, mating pairs of the Pale Mottle are quite regularly encountered, judging from the number of such posts on forums and butterfly groups on social media. Other species in the subfamily have occasionally been spotted mating in their preferred habitats in forested areas.

Mating pairs of Bigg's Brownwing (top) and Apefly (bottom)

The Bigg's Brownwing, Apefly and Lesser Darkwing are species that have records of mating pairs that have been encountered by butterfly photographers over the years. These are moderately common species and due to their caterpillars' carnivorous feeding habits, they are well distributed all over the island in a wide variety of habitats.

Mating pair of the Long Banded Silverline 

Of the subfamily Aphnaeinae, there are only 2 extant species in Singapore. Both species are not uncommon and can be found in habitats from urban parks and gardens to the forested nature reserves. Mating pairs are rarely encountered, but the Long Banded Silverline has been photographed mating.

Family : Lycaenidae Subfamily : Polyommatinae

This subfamily is often referred to as the "Blues", and are small delicate butterflies. Many of them have thread-like filamentous tails and are adorned with spots and streaks or iridescent tornal scales on the undersides of their hindwings. This is one of the largest group of butterflies compared to all the other families.

Mating pairs of the Grass Blues - Pygmy Grass Blue (top), Lesser Grass Blue (middle) and Pale Grass Blue (bottom)

Many of the species are very small in size, and the Pygmy Grass Blue (Zizula hylax pygmea) is the smallest species in the region. Mating pairs of the Grass Blues are not difficult to find, as they are urban butterflies and quite common. Lesser Grass Blue and Pale Grass Blue are the others that are usually encountered.

Mating pairs of the Indian Cupid (top) and the Malayan (bottom)

The rare Indian Cupid makes occasional appearances in Singapore, and then mysteriously disappears for long periods of time before showing up again. Interestingly, when they do appear, I have encountered mating pairs at least 3 times before. The Malayan, which is more common, is also featured here.

Mating pairs of Pea Blue (top), Gram Blue (middle) and Cycad Blue (bottom)

Other common species like the Pea Blue, Gram Blue and Cycad Blue are urban butterflies that can be found in our parks and gardens. These are species with long white-tipped filamentous tails and can be spotted in numbers at times, especially when their respective caterpillar host plants are abundant.

Mating pairs of Jamides and Nacaduba species

Mating pairs of the lookalike species of the genera of Jamides and Nacaduba are also regularly encountered. They are easier to photograph when mating and left undisturbed, as the species are generally active and always on the move unless feeding. Here are just a few examples of these species' mating pairs.

Mating pairs of the Two Spotted Line Blue (top) and White Fourline Blue (bottom)

Of special note are the Two Spotted Line Blue (Nacaduba biocellata) which is an exotic species of Australian origin. This species is very seasonal, where it appears in large numbers at certain times of the year and then disappearing altogether until the next outbreak. The next one is the White Fourline Blue (Nacaduba angusta kerriana) which is very rare, and only appearing for a short period and even was "common" for a short period of time when we were able to record its life history.

Family : Lycaenidae Subfamily : Theclinae

A mating pair of Green Imperial

The next large group of butterflies from the sub-family Theclinae features small, but robust-bodied, swift-flying species. The sub-family is also known for a number of spectacular long-tailed butterflies, of which many are forest-dependent species.

Mating pairs of various Theclinae species

Some are very rare and seldom seen, much less a mating pair! A photographer must be very lucky to see mating pairs of these species, like Semanga superba deliciosa, Scarce Silverstreak, Ambon Onyx and Acacia Blue. This is because the males of these species tend to stay more often at the treetops and the majority of individuals spotted are usually females.

Some long-tailed mating pairs - Branded Imperial (top), Common Imperial (middle) and Common Posy (bottom)

The long-tailed beauties like the Branded Imperial, Common Imperial, Green Imperial and Common Posy are more usually encountered in the forested areas of Singapore. But occasionally, mating pairs are spotted and provides good opportunities to photograph them in ideal environments with good composition and background.

Family : Hesperiidae Subfamily : Pyrginae

A mating pair of the Large Snow Flat

We come to the last of the six butterfly families in Singapore, the Hesperiidae or Skippers. The first sub-family Coeliadinae has very few records of mating pairs and are thus not featured here. The next sub-family, Pyrginae (or Flats) are represented by 12 species extant in Singapore. Thus far, only two species have been spotted as mating pairs, although others have been seen, but not photographed.

A mating pair of the Hieroglyphic Flat

Of the two species, the Hieroglyphic Flat has had a few occasions where mating pairs were spotted. This iconic butterfly is one of the prettiest skippers found here in Singapore. The other "Flat" which has a photographic records of mating pairs is the Large Snow Flat. Note that even when mating, the species are seen with their wings opened flat.

Family : Hesperiidae Subfamily : Hesperiinae

A mating pair of Bengal Swift

The final sub-family Hesperiinae features over 50 species extant in Singapore, and counting. Many of the species are cryptic and appear irritatingly similar to each other, making identification in the field very challenging. Coupled with their variability, in-species variability in markings and male-female differences, the Hesperiinae needs more research into their identifications.

Mating pairs of various skippers - Dark Banded Ace (top), Chestnut Bob (middle) and Grass Demon (bottom)

Mating pairs of the rare Dark Banded Ace (Halpe ormenes vilasina) have turned up once in a while, whilst the common Chestnut Bob, Banded Demon and Grass Demon mating pairs do show up more often. Even so, some of them are still as skittish and hard to photograph in the field when they are not in a cooperative mood to be photographed.

Mating pair of Banded Demon

Mating pair of the sexually dimorphic Quedara monteithi monteithi - the all-brown male is on the right, whilst the white banded female is on the left

A rare encounter with the sexually-dimorphic Quedara monteithi monteithi's mating pair shows very clearly the male-female differences. However, mating pairs of the more common Small Branded Swift and Contiguous Swift turn up more regularly, but harder to distinguish, as the sexes are almost identical.

Mating pairs from the genera Taractrocera (top), Potanthus (middle) and Telicota (bottom)

Of the last few genera of the orange-black species from Taractrocera, Potanthus and Telicota, photographs of mating pairs turn up once in a while, especially of the more common species extant in Singapore. The photos featured here are not exhaustive.

Mating pair of the Lesser Dart

And there you have it, a series of photographs of butterflies procreating, compiled from the creative works of many butterfly photographers over the years. There is no doubt that there will be more species recorded in the coming years as more and more photographers who are spending more time out in the field will surely encounter these paired butterflies.

Text by Khew SK : Photos by Sunny Chir, Chng CK, Antonio Giudici, Huang CJ, Khew SK, Koh CH, Lim CA, Loh MY, Loke PF, Neo TP, Richard Ong, Simon Sng, Tan BJ, Bene Tay, Tea YK, Anthony Wong, Mark Wong and Siaomouse Wong

It Takes Two! : Part 1