Whilst I was photographing these butterflies, I noticed that two males were closely associating with each other. But when I came to look at the images closely, it was apparent that they were not only absorbing liquids using their proboscises, but also secreting small amounts of liquid from the end of their abdomens. Quite what is going on, I don’t know, but it is interesting to record butterfly behaviour; there is so much we do not know about the lives of such species, and I hope this goes a small way to demonstrate the richness and complexity of the lives of living insects.
This butterfly is Vindula erota erota Fabricius, 1793: the Thai Cruiser. There are both Wet and Dry season forms of this species (1). This occurrence of different types or forms of the same butterfly species, in different seasons, is called ‘seasonal polyphenism’ and has probably evolved as an adaptation to the different environments – and the challenges they bring – in the ‘wet’ and ‘dry’ seasons of tropical regions. There is a theory (2) that in the dry season, when butterflies may spend quite a long time in a state of quiescence – waiting for the rains! – there is a greater need for the butterflies to be cryptic or hidden, to escape from their predators. In the wet season on the other hand – which is generally a time of reproduction and egg laying – it is better to adopt colours and patterns which can startle or deflect predators. Well that’s one idea. Whatever is going on, there are wet and dry season forms in many different butterfly species, so it is clearly a useful adaptation and may involve different behaviours as well as colours (2).
The sequence of photographs shown below are of dry season, V. e. erota males photographed on the 30 November 2015 in northern Thailand (Doi Chiang Dao). The timing of the occurrence of wet and dry season forms probably varies from place to place and females are said to exhibit more seasonal variation than males (3). I posted pictures of the slightly larger female, dry season form, in a previous blog (4). The female has a prominent whitish band which extend across the upperside of both wings, in contrast to a greenish-brown background colour of the wing (below).
The male is a much brighter orange brown colour, with black and brown spots and markings and a greenish tinge to the abdomen on fresh specimens (see below).
Males are commonly seen ‘mud puddling’ – absorbing moisture and salts. Females are seen much less commonly and I did not see any in this location on this occasion. I took a series of photographs of these butterflies on a sunlit patch of concrete on the steps leading up to a temple (Wat Tham Pha Plong) on the slopes of Doi Chiang Dao, Chiang Mai Province, Thailand (below).
Whilst I was photographing the butterflies, I noticed that two males were closely associating with each other. But when I came to look at the images closely, it was apparent that they were not only absorbing liquids using their proboscises, but also secreting small amounts of liquid from the end of their abdomens. Quite what is going on, I don’t know, but it is interesting to record butterfly behaviour; there is so much we do not know about the lives of such species, and I hope this goes a small way to demonstrate the richness and complexity of the lives of living insects.
The two interacting butterflies can easily be separated, as one had a couple of small notches – no doubt as a result of pecking damage by birds – on the apex of the right forewing (below). Let’s call him ‘Notch’.
The other butterfly was by contrast unmarked, let’s call him ‘Unmarked’ (below).
Unmarked was ‘puddling’ by himself – sucking up something good, salty or satisfying – on a sunlit piece of concrete on the steps. The abdomen was also noticeably curved downwards, as we will see again more clearly, below.
Unmarked carried on supping in the sun, slowly opening and closing his wings and gradually lowering the tip of his abdomen and pressing it onto the ground.
Then along came Notch, landing next to Unmarked, and started feeding right next to him in exactly the same way.
Notch gradually moved closer to Unmarked and placed his wings exactly along side Unmarked’s wings, mirroring his position. I got the impression that they were pressing against each other. The wings were so closely aligned that it looked like they had wanted to be side by side; but what was the purpose of this behaviour? They were both engaged in absorbing something liquid from the ground.
Together they carried on feeding and pressing up against each other.
In this photograph (below), they are both dipping their proboscises in the same small patch of liquid.
This carried on for some time and I started to get a bit tired, lying on the ground in the sun, propping up my macro lens with my elbow. Passing Thai people and monks were tolerant and fortunately used to Farangs – foreigners – doing unusual things! They could see that I was photographing butterflies, which all good Buddhists revere.
Unmarked eventually flew off. Then Notch did something I only noticed after I looked closely at these photographs on the computer. The butterfly angled the tip of his abdomen downwards and appeared to deposit a small quantity of liquid on the concrete (below).
I consulted butterfly expert Professor Dick Vane-Wright, who suggested that the butterfly might have been ‘recycling’ something that it has already voided from its anus – the proboscis is reflexed backwards, perhaps to absorb the exudate – a behaviour which Professor Vane-Wright reported that he had seen before in skippers and swallowtails (pers. comm.).
Whatever the significance – or not – of this behaviour, it provides a nice example of glimpses we can get into the lives of insects, by taking photographs. The excellence of modern digital cameras and lens – even relatively inexpensive compact cameras will do – allows us to record behaviour in a way which would have amazed butterfly admirers of old.
These aggregations of puddling butterflies usually consist largely of males, which are thought to be replenishing their sodium-reserves, lost (or soon to be lost) in the process of delivering a spermatophore to females during mating. Or more prosaically, it may be to enable the males to produce a ‘nuptial gift’ in the form of sodium, for the females.
When visiting Doi Chiang Dao – a place I have written about before (1) – last November (2015), I came across some interesting aggregations of butterflies; composed mainly of Blues (lycaenids) and Yellows (pierids). I may have been a little bit late, as October is said to be the best month to see butterflies in this area, but there were still large numbers of them around.
The place with good aggregations of butterflies is at the army camp at the entrance to Chiang Dao Wildlife Sanctuary (2), where most of the photographs shown here were taken.
The soldiers place fruit and dead fish to attract the butterflies; fermented fish mixed with fermented pineapple extract was found by researchers to attract the most species (3).
I came across a Common nawab (Polyura athamas) feeding on the dead fish (below). It might be common, but it is, like all nawab butterflies – species in the genus Polyura – exquisitely marked and very attractive. Presumably, the patterns and colours have a more practical purpose than to satisfy our aesthetic yearnings!
The Yellows appeared to be mainly Changeable Grass Yellows (Eurema simulatrix), also called Hill Grass Yellows. There were also other yellow pierid species present in smaller numbers, including Yellow Orange Tips (Ixias pyrene), and probably others. Common and Three-spot Grass Yellows all look very similar, at least to my untrained – in pierid taxonomy that is – eyes!
There were also lots of small, black-and-white butterflies – called Pierrots – present, including: Straight, Elbowed and Banded Blue Pierrots (Caleta roxus, Caleta elna and Discolampaethion,respectively).
There are various subspecies of these widely distributed butterflies which I do not feel competent to identify, other than by location.
There were also fairly large numbers of Zebra Blues (Leptotes plinius), Common Ciliate Blues (Anthene emolus) and Plain Hedge Blues (Celastrina lavendularis). There were probably other species, including The Bi-spot Royal (Ancema ctesia ctesia), present amongst the aggregations; remarkably at least 426 species of lycaenids have been recorded in Thailand.
Like the Yellows, all of these Blues and Pierrots like puddling, or mud puddling: sucking up salts on moist ground or for example, from dung, carrion or bird droppings.
These aggregations of puddling butterflies usually consist largely of males, which are thought to be replenishing their sodium-reserves, lost (or soon to be lost) in the process of delivering a spermatophore to females during mating. Or more prosaically, it may be to enable the males to produce a ‘nuptial gift’ in the form of sodium, for the females (4). Absorbing nitrogen-rich resources will also give the males added “oomph” or, in other words, increase their reproductive success (5).
If this blog has whetted your appetite and you want to see some better, truly amazing macro photographs of butterflies from this location, then I recommend this website (6), which shows the beautiful photographic work of Antonio Giudici (7). I can only aspire to the quality of his work, but I have ordered a better macro lens for my next visit! I think the last word should be with the mountain (below).
It is said that 50% of wild butterflies are killed and eaten before they get a chance to mate and reproduce (1). Poor things! One way to avoid being eaten is to divert the lethal pecks of predatory birds towards body parts that can be sacrificed in the interests of survival. Obtaining direct evidence for the protective utility of eyespots is difficult, but the deflective function of marginal eyespots has been demonstrated in some studies. It has also been shown to work well under low light conditions – such as at dawn and dusk – when birds are most active (2).
Photographs of butterflies often show evidence of extensive damage. Whilst such evidence of ‘beak marks’ – damage caused by a would be predator – is only circumstantial, it is a good indication of the fact that it is a regular occurrence in nature. Indeed, photographs could perhaps be used as a research tool into the intensity of such attacks, although one would only observe the survivors! The others would be inside the birds stomachs. Once pecked, as in the above photograph, the eyespot may be lost, so the butterfly is presumably more vulnerable to subsequent attacks. It has also been shown that eyespots can function in different ways in different seasons: eyespot plasticity! In the dry season, eyespots are a liability, so natural selection has resulted in the evolution of a spotless form – able to blend in well against brown, dead leaf litter – and another form, with eyespots, in the wet season, where they have an evolutionary useful deflective function (3).
Another feature which has become obvious to me as I have taken more and more photographs of butterflies, is that they are seemingly able to fly about and carry out their lives, despite sustaining considerable damage to their wings. Some of this may be simple ‘wear and tear’ as well as predation damage. I have written about this before (4)! It’s a subject which fascinates me for some reason! Perhaps its something to do with our universal fragility? Compare these two images, below. The first, a highly worn and presumably ‘old’ butterfly – a male Clipper, Parthenos sylvia apicalis. The second, a much fresher specimen of the same species – but nevertheless, still sporting a beak mark on the left hind wing – which only became apparent to me after I photographed it and looked at the image on my computer. Yet both individual butterflies were gaily flying around and resting to feed on flowers. Indistinguishable to the casual observer. For some reason, perhaps to do with age, I take comfort in this fact!
All three images were taken in Doi Chiang Dao, in northern Thailand.
Tinolius is a genus of five striking moths in the family Erebidae (Noctuoidea), sometimes called Owlet moths. The forewings are buff coloured with different numbers of white spots; the abdomen is pale red or yellow with lateral black bars on each segment.
The male antennae are strongly bipectinate – meaning that they have two margins – toothed like a comb – a bit like a feather (below). This species has one less white spot than the one above, but I have not seen able to name it.
The larvae of these moths are described as being ‘ophiusine’ semi-loopers (1). They have very long and fine setae, some of which are elongated and flattened at their ends into black blades. They really are extraordinary looking caterpillars. Quite what the function of the paddle-like structures is, other than defence, I don’t know. There is very little in the on-line literature on these remarkable insects.
All of these photographs were taken in northern Thailand, at Doi Chiang Dao.
Zahiri, Reza, et al. “Molecular phylogenetics of Erebidae (Lepidoptera, Noctuoidea).” Systematic Entomology 37.1 (2012): 102-124.
Asota plana Walker, 1854. A moth in the family Erebidae in the superfamily Noctuoidea which is found between 1,000 to 1,900m. I took this photograph at Doi Ang Khang, in northern Thailand, well below the peak at 1,928 metres. The subspecies Asota plana plana is found in China, India, Indonesia, Japan, Laos, Malaysia, Myanmar, Nepal, Sri Lanka, Thailand and Vietnam. The larvae are very striking, coloured black with yellow rings around each segment and festooned with long white hairs; definitely aposematic! (1). The host plant is said to be Ficus (Moraceae).
The moth flew onto a pane of glass, which resulted in an attractive photograph (below) even though it was taken with a small compact camera. I have rotated the image from the vertical to the horizontal plane for added impact! It is one of my favourite images and shows that you do not need to spend a lot of money on equipment to get interesting images. But you do need to get lucky now and then!
The large, and very attractive moth, Asota (=Anagnia) subfascia, shown below, is another member of this genus. This specimen appeared on the balcony outside my hotel room one night in Pattaya. Another species with a wide distribution, including India, Thailand, Peninsular Malaysia, Indonesia, the Philippines and Taiwan. It seems to have gone through a number of name changes as it was also previously named, Peridrome subfascia Walker, 1854.
The caterpillars of this species – the Spurge Hawk-moth (Hyles euphorbiae) – are highly variable and there are many different subspecies; some of which are now regarded as separate species (1, 2). In fact, it seems to be a taxonomic nightmare! First of all, the Hyles genus itself comprises “a complex of species, subspecies and forms, all closely related to Hyles euphorbiae” (3). Secondly, the species complex called Hyles euphorbiae “is rather difficult to classify for it would seem to be in the process of diverging into a number of species” (3). Thirdly, some of the subspecies have crossed with each other to form localised hybrid populations in some parts of Europe!
The yellow, black and white larva (with orange prolegs!) shown here is probably Hyles euphorbiae euphorbiae, as itlooks very similar to photographs of other larvae collected from the same area (Serres) in northern Greece (3). They feed on species of Euphorbia, which they consume with great gusto and if disturbed, eject “a thick stream of dark green fluid” said to be “rich in phorbol esters, which are potent toxins and irritants” (3). So you have been warned!
This complex of species and subspecies would seem to be a great opportunity to observe evolution in progress, and some researchers are doing just that (5, 6). The problem is that taxonomists have sometimes disagreed as to whether certain forms are completely different species, or just distinct subspecies. Interestingly, and this is by no means unique in rapidly diverging species, the adult genitalia – features beloved by classical lepidopterists – are of “little use as they show practically no difference between taxa” (3). Fortunately, the colour and patterns of the larval stages do “provide a very good guide to the relationships between the many ‘species’ and ‘subspecies'”, although there is some overlap (5). This is analogous to a study which found ten cryptic species lurking within indistinguishable adults of a neotropical species (in Costa Rica) that did however, have distinctly different caterpillars (and feeding preferences) (4).
Molecular studies – using mitochondrial DNA sequences – are also coming to the rescue of the Hyles euphorbiae complex (HEC) (5). It seems that the different lineages within the HEC complex arose as a consequence of geographical isolation in Pleistocene refuges in Europe, during the Ice Ages (6). But there are unresolved issues concerning the separation of different forms, or haplotypes, using mitochondrial DNA (see reference 6 for a discussion).
Hebert, Paul DN, et al. “Ten species in one: DNA barcoding reveals cryptic species in the neotropical skipper butterfly Astraptes fulgerator.” Proceedings of the National Academy of Sciences of the United States of America 101.41 (2004): 14812-14817.
Hundsdoerfer, Anna K., Ian J. Kitching, and Michael Wink. “The phylogeny of the Hyles euphorbiae complex (Lepidoptera: Sphingidae): molecular evidence from sequence data and ISSR-PCR fingerprints.” Organisms Diversity & Evolution 5.3 (2005): 173-198.
Mende, Michael B., and Anna K. Hundsdoerfer. “Mitochondrial lineage sorting in action–historical biogeography of the Hyles euphorbiae complex (Sphingidae, Lepidoptera) in Italy.” BMC evolutionary biology 13.1 (2013): 83.