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Night brings with it a sense of enigma. Darkness, and everything associated, is one such thing. This is more pronounced because of the fear instilled in us during our formative years. The familiar path that we tread with ease during daytime, under the cover of darkness, is full of ‘hurdles’ that often don’t physically exist. This primarily is due to our dependence on our vision. It also prevents us from exploring our environment under the night sky. For most urbanites who are used bright light even after sunset, it is a world that does not exist.

Imagine yourself in the midst of a dense forest with no torch to guide you along the path. The only available light is the faint glow of the night sky to vaguely light your path. Close your eyes for a long second. And, when you open your eyes, you see streaks of faint green glow on the forest floor. Look hard and you will see that some tree limbs around you have the same eerie glow. So much so that it sends a shiver down your spine.

When your eyes are used to the dark  you see the forest floor scattered with the eerie glow!

When your eyes are used to the dark you see the forest floor scattered with the eerie glow!

 

For those who are not aware of the presence of bioluminescent fungi, it can be spooky. But for the informed, who has been aching to see this phenomenon– it is a treat. You shine the torch and you see a normal dry twig. Switch it off and get used to the darkness… you see the twig glow again!

Twigs on the forest floor - it looks like any other twig under normal light.

Twigs on the forest floor – it looks like any other twig under normal light.

 

The same twig in the dark!

The same twig in the dark once your eyes get accustomed to the darkness!

 

I have in the past written about glow worms where I have discussed some aspects of bioluminescence and also mentioned that the light produced by these creatures does not produce heat.

The bioluminescent fungus too produces the faint glow in a process which is akin to that used by the glow worm. The growing part of the body of the fungi (hyphae) which is present in decaying plant matter is responsible for the glow.

Only about 70 species of fungi are known to be bioluminescent. This is a very small number if you considered the diversity of fungi in the world – over 70,000 known species! Why they glow, what benefit they derive is not very clear. However, some preliminary observations suggest that the bioluminescence could attract insects which help in dispersing spores!

A recent attempt to better previous results at capturing this beautiful phenomenon.

A recent attempt to better previous results at capturing this beautiful phenomenon.

 

Like the bioluminescent fungi, there are a lot of organisms that are best seen and appreciated under the cover of darkness. Resist the urge to switch on that torch. Step outside your comfort zone – at least once in a while. And enjoy what Nature has to offer.

One morning last week, when I came out of my room, I was treated to a very interesting sight. A Coucal. The booming calls of the Coucals are often heard and the birds themselves are seen regularly in our garden. The bird came out of the bush and landed on a stone slab nearby. On close observation, I noticed something in its beak. It was a large juicy green caterpillar (probably of the Oleander Hawk Moth) in its mandibles! The caterpillar (or larva) was gulped down in no time. The whole drama happened so quickly that there no time to capture this event.

Tabernaemontana bush.

Tabernaemontana bush.

 

However, it reminded me of a similar event that had transpired many years ago – to be more precise February 2006! One afternoon I noticed some movement near the top of the same Tabernaemontana bush. I waited for a while and noticed movement again. This happened a few times. I could not contain my curiosity and ran into the house to get my binoculars. Gazing through them, I noticed a fat green caterpillar with an outward pointing stiff tail. Also, nearby was a Garden Lizard Calotes versicolor.

Garden Lizard and the larva of the Oleander Hawk Moth.

Garden Lizard and the larva of the Hawk Moth.

 

The lizard lunged at the caterpillar and barely managed to get a hold. But it had to let go since the caterpillar had a stronger grip of the twig! The lizard repeated this effort several times. Unable to get much purchase with its tiny teeth, with each effort it only managed to injure the caterpillar.

The Garden Lizard attacking the larva.

The Garden Lizard attacking the larva.

 

Until eventually the green gooey innards of the caterpillar was threatening to fall out.

Notice the green innards of the larva exposed.

Notice the green innards of the larva exposed.

 

 At this stage, the lizard decided to abort the effort and go away. This came as a surprise to me. The lizard had invested ample time and effort to maim the caterpillar. A little more and it would have been rewarded with a juicy morsel. I am not sure if it was the exposed innards of the caterpillar that forced the lizard to quit. Unfortunately, the caterpillar became neither meal nor moth!

This time around, since the drama went on for longer, I managed to get a couple of frames of another predator of the same caterpillar!

Pond Skater

All of us, during our childhood, must have made paper boats and let it float on water. Unknowingly, we had accessed the physical properties of water to indulge in those moments of joy.

The marvels of a paper boat or a leaf gently floating over water are both possible because of the surface tension of the water. The strength of this force is adequate to support light objects and prevent them from sinking. We learnt this and a lot more about water as we grew up, but often failed to relate it to the floating boat.

Dimples on the water surface !

Dimples on the water surface !

 

The Pond Skaters, also referred to as the water-striders, is a group of true bugs that have taken to an aquatic life-style. They, to stay afloat, use the surface tension of water too! They can be found in most ponds, lakes and rivers, preferably in more still waters.

A congregation of pond skaters.

A congregation of pond skaters.

 

Like all insects, the pond skater has 6 legs. They (body and legs) are also covered with water repelling hair which further helps the insect to stay afloat. Only 4 legs (2nd and 3rd pair) are prominently visible. These are long and help to distribute the weight of the insect and to propel it on the water surface. The other 2 legs (1st pair) are the shortest and help in detecting vibrations/ripples on the water surface. This ability helps the pond skater to detect other small insects that may fall on the water. Once detected, it will swiftly ‘skate’ to the source of the disturbance, use the claws on the first pair to puncture the prey and eventually suck it dry!

Pond skater feeding.

Pond skater feeding.

 

Look around, observe nature carefully, there is plenty to learn – for that matter even refresh and recollect what we have learnt during our school days and relate them to nature better. Whoever said Nature is only about Biology!?

Bagworm

Many of us may have noticed a little brown speck of ‘dirt’ stuck to the walls in our homes. It looks like a blot on an otherwise clean wall or should I say on our house-keeping skills? Often, it is promptly removed and disposed. If you were the procrastinating type perhaps you noticed that the speck has moved and it is no longer in the same place on the wall. If you happen to be curious, you would have figured out just what that moving brown speck of is!

One of more commonly seen bagworms - seen on the walls both inside and outside of homes.

One of the more commonly seen ‘specks’- seen on the walls both inside and outside of homes. This one belongs to family Tineidae and referred to as case worms.

 

We are talking about what is popularly referred to as bagworms. What are bagworms? They are a small family of moths belonging to family Psychidae. This family comprises of over 1300 species of the 1.3 lakh species or so moths in the world.

There is something unique about this family of moths. The larva, soon after emerging from the egg, builds a little case. For this purpose it uses the silk that it produces and material available in their environment – could be lichen, tree bark, twigs, sand, leaves etc. It can be seen with just a bit of its body protruding out when it is moving about.

A bagworm using debris to decorate itself !

A bagworm using debris to decorate itself !

 

Once its growth as a larva is complete, it will pupate within the ‘bag’ it had built as a larva. The males of most species have wings like other moths and will fly away. However, the adult females often lack wings and look like the larva itself! The males are very short lived. They even lack mouthparts and don’t eat as adults. So the males have to locate females as soon as they can and mate with one. They do this by following the pheromones produced by the females. Eventually, they mate and the females lay eggs within the ‘bag’ and die. The females too live just long enough to mate and lay eggs. Like the males, the females do not eat as adults. And, this entire process continues generation after generation.

In the outdoors, one can find a variety of ‘bags’ built by these little creatures. Some of them are really amazing feats of engineering, while some others look clumsy to help them camouflage beautifully with their environment. Below are some such ‘bags’.

Twigs are used to make this 'bag'. This is also a fairly common sight in places with some shrubbery.

Twigs are used to make this ‘bag’. This is also a fairly common sight in places with some shrubbery.

 

This structure looks more like a broken 'twig' ! It is amusing to watch this twig move about.

This structure looks more like a broken ‘twig’ ! It is amusing to watch this twig move about.

 

What looks like pieces of bark have been stuck together by this bagworm. What is even better is that it looks like an extension of the tree - excellent camouflage indeed !

Pieces of bark have been stuck together by this bagworm. What is even better is that it looks like an extension of the tree.

 

A 'bag' constructed using sections of leaves !

A ‘bag’ constructed using sections of leaves !

 

Two examples for usage of twigs - one neatly stacked and the other seemingly disorganised.

Two examples for use of twigs – one neatly stacked and the other seemingly disorganised. Both serving the purpose indeed.

 

But this takes the cake  for the engineering. Hollow twigs cut to the right length and organised into a tapering spiral!

But this takes the cake for its engineering. Hollow twigs cut to the right length and organised into a tapering spiral!

 

So, the next time you see one of these aggregations of material – be it twigs, leaves, bark, etc., – give it another look. Lo and behold you may have discovered another beautiful piece of engineering – a bagworm!

See more images of Bagworms

Moon Crab

Sun, sand and surf are all that comes to mind when planning a trip to the beach. These three elements almost invariably cloud out everything else. If anything else, we might indulge in building sand-castles or perhaps long walks on the sand at sunset!

It was one such evening while walking along the water’s edge during a visit to the Devbagh Beach Resort near Karwar that I was treated to one of the most beautiful creatures that I had ever seen – probably a crab. Spines on either side of its body and legs that were flattened gave it a very non-crab appearance at first sight.

The creature that I was staring at had an almost circular body which was about 4 cm across. But the flattened appendages intrigued me and left me wondering what these adaptations could possibly mean.

The Moon Crab Matuta sp. at Devbagh, Karwar.

The Moon Crab at Devbagh, Karwar.

 

This was the Moon Crab (Matuta sp.), also sometimes referred to as the Sandy shore crab. It spends the day buried in sand. Its spade-like appendages are used to dig into the sand and for swimming!

When these crabs come out to forage in the night, they are known to feed on small creatures – be it worms, clams, and other small animals – that they can overpower. They also seem to have a special taste for dead fish!

Face-to-face with the Moon Crab.

Face-to-face with the Moon Crab.

 

Adult females have been found to be capable of producing more than one batch of eggs from a single mating with each batch containing about 65,000 eggs!

Moon Crabs have a very wide distribution. They are known to occur all the way from the Red Sea, through much of Asia to Australia where it is common in the Great Barrier Reef.

Assassin Bugs

It was during my second, albeit brief, visit to Port Blair that I got an opportunity to trek in the wilderness of the Andamans. The trek was from Shoal Bay to Madhuban. The distance that we had planned to cover was short, but it seemed to take forever to reach the destination. A multitude of small fascinating organisms kept vying for attention all along the way and this slowed us down enormously.

The ‘star’ of the trek turned out to be a weird and strange looking creature that we spotted on a spider web about 5 feet from the ground. It kept moving constantly, making it very difficult even to lock focus. It had a long body and even longer legs that were wiry. I could not venture very close to get all the details for fear of not seeing the complete insect in the frame. Three pairs of legs (the first set resembling those of a praying mantis); a pair of long antennae; it being on a spider web; all had me confused no end. It was only recently (after 3 ½ years!) that I managed to put a name to this enigma. It turned out to be what is popularly known as the ‘Thread-legged Bug’.

Thread-legged Bug on a spiders web, Andamans.

Thread-legged Bug on a spider’s web, Andamans.

Very little is known about the Thread-legged Bugs. Though these bugs have a wide distribution, tropics have the highest diversity of species. These predatory insects are known to be nocturnal and they occur in a variety of habitats including spider webs. Some species are even known to steal prey caught in spider webs!

The Thread-legged Bugs belong to a much larger group of bugs called the assassin bugs (Family Reduviidae). This is a very diverse group of which there are around 6000 known species. All assassin bugs, as one would expect, are predators. They are characterised by the presence of a very prominent ‘beak’.

The beak is used to pierce the prey and inject saliva thereby paralysing them. The saliva helps in digesting the contents of the prey. Subsequently, the assassin bug sucks the contents leaving behind an empty shell! This behaviour is what gives them their name.

Assassin bug nymph feeding on a moth attracted to light, Goa.

Assassin bug nymph feeding on a moth attracted to light, Goa.

Assassin bugs are known to occur over most parts of the world. Though I have often seen assassin bugs, it came as a surprise when I learnt that the Thread-legged Bug occurs even in cities – it can be seen in and around Bangalore too. So keep a watch around you and when you do encounter one, you may do well to leave it alone since assassin bugs can deliver a painful bite!

Assassin bug feeding on an aphid, K.Gudi.

Assassin bug feeding on an aphid, K.Gudi. Assassin bugs could be of potential value in pest control.

Ever since I got interested in nature, I have always had this feeling that there are creatures constantly watching me. Also the feeling that I have missed more than I have seen has also bothered me. And I have often wondered why I don’t get to see them.

The answer seems to be in the ability of organisms to blend in with their surroundings – in other words – camouflage! Over the years, I have come across creatures, predominantly small ones – both prey and predators, that have evolved some amazing camouflage.

In this photo feature, I bring you a dozen images from my collection representing insects, spiders and reptiles – all of which are very well camouflaged in their respective habitats. This is an attempt to showcase some of my observations of the these beautifully camouflaged beings! I know the nagging feeling that I have missed something is still there and will continue to bother me. Don’t blame me if you start feeling likewise after seeing the images below!

I would like to thank Shyamal for identifying some of the insects that are featured here.

Flying Lizard Draco dussumieri, Dubare : The presence of this lizard becomes obvious away only when it moves or when it is extending and collapsing the bright yellow gular sac.

Bark Gecko Hemidactylus leschenaultii, Bheemeshwari. Seen living on trees and difficult to spot even for a trained eye.

Bark Gecko Hemidactylus leschenaultii, Bheemeshwari : Seen living on trees and difficult to spot even for a trained eye.

Two-tailed Spider Hersilia sp. - Kabini. This spider can be seen most often on trees. However, it can be seen on walls of buildings in the city too.

Two-tailed Spider Hersilia sp. – Kabini : This spider can be seen most often on trees.

Moth - Bangalore. I chanced upon this beauty in my back yard. Just goes to show how easily creatures in our midst could be missed out !

Moth – Bangalore : I chanced upon this beauty in my back yard. Just goes to show how easily creatures in our midst could be missed out!

Bug , Bangalore. This nymph was sitting in a fissure on the bark of the tree and completely motionless.

Bug, Bangalore : This nymph was sitting in a fissure on the bark of the tree and completely motionless.

Bug, Dubare. It was while I was searching for spiders that I espied this amazingly camouflaged bug.

Bug, Dubare : It was while I was searching for spiders that I espied this amazingly camouflaged bug.

Bug, Bangalore : This nymph is another example of stunning camouflage.

Bug, Bangalore : This nymph is another example of stunning camouflage.

Plant hopper, Goa : This fulgoromorph looked more like a piece of moss growing on the trunk.during the rains.

Plant hopper, Goa : This fulgoromorph can easily be passed off as a piece of moss growing on the trunk during the rains.

Plant hopper, Bangalore : Another fulgoromorph on the bark of a tree during the drier months.

Plant hopper, Bangalore : The pattern on the hopper is so deceptively similar to the bark of a tree during the drier months.

Grasshopper, Goa : The genus (Phyllochoreia) to which this grasshopper belongs is endemic to Western Ghats and Sri Lanka.

Grasshopper, Goa : The genus (Phyllochoreia) to which this grasshopper belongs is endemic to Western Ghats and Sri Lanka.The strong resemblance to a leaf had me completely fooled.

Praying mantis, Bangalore : This mantis lives almost entirely on trees and has colour forms that blend with trees on which it is !

Praying Mantis, Bangalore : This mantis lives almost entirely on trees and has colour forms that blend with trees on which it is!

Praying Mantis Gongylus sp., Kabini : Though I had seen individuals of this in Bangalore many years ago, seeing and photographing this was very exciting. It is interesting to see how all these creatures always seem to find the right substrate to blend in !

Praying Mantis Gongylus sp., Kabini : Though I had seen individuals of this in Bangalore many years ago, seeing and photographing this was very exciting. It is interesting to see how all these creatures always seem to find the right substrate to blend in!

Every day that I have walked into my office building this week, I have been welcomed by a mild, enjoyable and a heavenly aroma. Out of curiosity my eyes wandered and espied the tiny white flowers borne on long spikes. I remember noticing that this tree, near the entrance, was almost bare just a month ago. Today, it stands in full glory with the dark green leaves providing a lovely background to the equally beautiful and delicate inflorescence. Indeed, a delectable transformation!

What was even more interesting was that the flowers were attracting a lot of butterflies. The Blue Tigers and Crows that are on their annual migration seemed to find the flowers worthy of a visit before they continued their journey. The honey bees were busy visiting the flowers too. Other butterflies like the Common Jezebel, Common Jay and the Tailed Jay were also attracted to the flowers.

Citharexylum spinosum - entire inflorescence.

Citharexylum spinosum – entire inflorescence.

The Fiddlewood tree Citharexylum spinosum, of which there are very few in the city of Bangalore, was the source of the fragrance and the activity. I am personally aware of very few trees – one in my office premises, one in Basavangudi (not far from Ramakrishna Ashram circle) and a couple of trees in the campus of the Indian Institute of Science.

The tree is a native of tropical America and West Indies. As can be guessed, it gets its name from the fact that the wood is used in making musical instruments.

The Fiddlewood is not a very big tree. It grows to about 30-40 feet tall and does not have a spreading canopy. It can also be grown in spaces with little or no shade. All this, along with a long flowering season and fragrant flowers, makes the tree an excellent candidate for landscaping purposes and as an avenue tree. The tree can be propagated from seeds and from semi-hardwood cuttings.

Citharexylum spinosum - close-up of flowers.

Citharexylum spinosum – close-up of flowers.

So, the next time you find one of these trees, pause for a moment – appreciate the fragrance of the flowers or watch the butterflies visiting them. The time and effort will be well worth it and also a welcome relief to any urbanite.

Stonefly

The sun slowly disappeared behind the hills. The colour of the sky changed hues by the minute. I was at the banks of the Cauvery at Galibore sitting under a gigantic Arjuna tree Terminalia arjuna, soaking in the lovely evening.

Soon it became dark and was now the time for the stars to adorn the sky. A small lantern was brought in and placed on the table. In no time the lantern attracted scores of small insects – some familiar, some too small and some that made a brief appearance, not to be seen again.

Among these visitors was one little insect that decided to move about in the area where the lantern cast its light. It was neither unusual nor colourful. On the contrary, it looked like any other insect and was a dull brown except that it had a flatter appearance.

It had black beady eyes, a pair of antennae. A pair of tail like organs (cerci) that was very noticeable attracted my attention. So, it was photography time! I shot several pictures of this very active little insect until I was satisfied with what I got.

Later, when I was reviewing the pictures I realised that I had seen this insect earlier. The previous occasion was also close to the water and I had then identified it as a Stonefly (Order Plecoptera).

Stonefly

Stonefly

Stoneflies, like you may have guessed, spend their early days in water. The aquatic nymphs are in found in streams, along shores of lakes and often under stones. Now you know where they get their name from! The nymphs live in water until it is time for them to emerge as adults. Some of them have a very long nymphal stage –in some species lasting up to 3 years. Most stone flies do not feed as adults and those that do are known to be herbivorous. As adults they are not good fliers and hence seen in the vicinity of water bodies.

Reproducing is the main responsibility of adult insects. It is not different for stoneflies. To this end, the male stonefly has evolved a very interesting way of attracting the female. He taps on the substrate (often waterside vegetation) with his abdomen! Unmated females respond to this by drumming themselves. And the drumming signals are specific to each species!

I will leave you with another interesting aspect of the stoneflies before I close. These insects generally require unpolluted waters to survive. Hence their presence in a water body is (thought to be) an indicator of very good water quality!

Moulting spiders

It was during the latter half of the eighties that I witnessed an extraordinary event; an event that even to this day leaves me marvelling when I think about it!

Seeing a tarantula is an exciting experience in itself; but witnessing one moulting is even more so! I had the fortune of witnessing a tarantula which had just started to moult. The exoskeleton covering the carapace (cephalothorax; the first segment of a spider’s body) had just split from the exoskeleton covering the chelicerae (the organ that houses the fangs).

As I watched, the split widened and eventually the entire carapace separated from the rest of the exoskeleton barring a hinge attaching it to the abdomen. Next, the pedipalps (leg-like appendages next to the fangs) came out one after the other. One by one, the fangs and all the appendages came out! The last to come out was the abdomen as the spider crawled out leaving behind an almost intact skin (exoskeleton)! The tarantula with its new exoskeleton looked beautiful; the colour of the spider was darker and brighter and the fangs were white. The fangs turned to a deep brown as time passed. The ‘fresh’ spider sat still for a long time without any perceptible movement, allowing the new skin to dry.

The whole process took close to two hours as I sat, transfixed, watching it. The unfortunate part of the story is that I did not have a camera those days to document this fascinating natural history event.

All spiders, like other arthropods, have an exoskeleton that is restricting. It has to be shed periodically for the spider to be able to grow. The frequency and the number of times a spider moults, depends on the species, age and sex of the individual.

I had described one such incident earlier involving a grasshopper.

From the time, I rediscovered my interest in spiders in the recent times, I have seen tarantulas several times. I have also come across the shed exoskeleton but I have not been lucky enough to see another tarantula moulting. Nevertheless, I have chanced upon many other spiders doing so and the watching the process continues to fascinate me!

Events like this are happening all around us – in our little gardens or perhaps within our own homes. Look out and you may be rewarded. Here, I leave you with these two images of spiders moulting.

Giant Wood Spider moulting.

Giant Wood Spider moulting.

Ant mimic spider with discarded exoskeleton.

Ant mimic spider with discarded exoskeleton.

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