The Malayan Five Ring (Ypthima horsfieldi humei)
We've reached the penultimate month of 2024 and the cool wintry weather is upon many countries in the northern hemisphere. Over in West Malaysia and Singapore, we have been inundated by heavy rainstorms over many days of the month as flood alert warnings are typical on both sides of the Causeway. Over in the east coast of West Malaysia, where the north-east monsoons are more severe, Malaysians are preparing for the worst floods in a decade. Thus far, fatalities have already been reported, and tens of thousands of residents displaced from their homes.
Over in the temperate countries in the northern hemisphere, temperatures are plummeting as residents prepare for colder winters ahead. South Korea's capital, Seoul, was blanketed on 27 Nov by the heaviest November snowfall since records began over a century ago, with more than 200 flights cancelled or delayed due to the weather conditions. Whilst residents enjoyed the sights and experience of a white Seoul, others who were affected by power outages and delayed travel plans weren't so happy about the snowfall.
A mating pair of Malayan Five Ring
Again, the impact of climate change can be correlated with continued evidence of these extreme weather conditions which are getting more often in recent years.Even the number of incidents of "air pockets" where turbulent conditions affected air travel in recent years. Some researchers think that climate change has made turbulence more likely. Last year, scientists at Reading University in the UK found that severe turbulence had increased 55% between 1979 and 2020 on a typically busy North Atlantic route. They put the increase down to changes in wind speed at high altitudes due to warmer air from carbon emissions.
This month we feature a rather controversial species as far as its taxonomic identity is concerned. A common species that is often overlooked as it is unremarkable and drab, the Malayan Five Ring (Ypthima horsfieldi humei) and its lookalike cousin, the Common Five Ring (Ypthima newboldi) are often mistaken for one another. In fact, there is some measure of discussion and disagreement amongst butterfly taxonomists as to whether they are a single species, a subspecies, or two distinct species.
Whilst the taxonomists continue to debate on this species, we take a look at this widely distributed butterfly where it occurs across Singapore along forest edges and open grasslands. The Malayan Five Ring is a weak flyer and usually stays close to the ground in semi-shaded grassy areas in the vicinity of our nature reserves.
A Malayan Five Ring opens its wings as it is feeding on the flowers of the Bandicoot Berry (Leea indica)
The upperside of the Malayan Five Ring is a pale brown with a large yellow-ringed ocellus on the forewing. Two pairs of ocelli are also typically seen on the upperside of the hindwing when the butterfly opens its wings to sunbathe or when feeding.The post-discal areas on both wings are usually lighter, with the basal area and margins of the wings a darker brown.
On the underside, there are five ocelli arranged in pairs - in spaces 6 and 5, 3 and 2 and the double tornal ocellus at space 1b. In typical examples of this species the ground colour of the wings is lighter (compared with Y. newboldi) and the ocelli in spaces 2 and 3 are distinctly separated. In Y. newboldi, these two ocelli are contiguous or touching each other, and the pair in spaces 5 and 6 are usually contiguous. In the Malayan Five Ring, these ocelli are typically well separated.
The Malayan Five Ring's preferred habitat is forested areas and secondary growth, where it can sometimes be quite common. They prefer to stay close to the ground and have a habit of opening their wings to sunbathe in the morning hours of a sunny day. At other times, it will stop on the upper surfaces of leaves with its wings closed upright.
A mating pair of Malayan Five Ring perched on their caterpillar host plant, Axonopus compressus
It has been successfully bred in Singapore on various grasses Axonopus compressus (Common Cow Grass), Ottochloa nodosa (Slender Panic Grass), and Kyllinga nemoralis (White Kyllinga). The life history of the Malayan Five Ring is fully documented from egg to adult in this blogpost.
Text by Khew SK : Photos by Huang CJ, Khew SK, Loh MY, Low JK, Michael Soh and Horace Tan
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