Yellow Flower Mantis
Parhymenopus davidsoni
Malaysia has a rich Praying Mantis fauna which includes some of the world's most beautiful species. Such mantises of amazing shapes and vibrant colour patterns often belong to the subfamily Hymenopodinae. Certain species of this subfamily like the Orchid Mantis Hymenopus coronatus, Banded Mantis Theopropus elegans and several Creobroter spp. are usual exhibits in live insect exhibitions and zoos around the world. Unfortunately for mantis lovers, it is not easy to breed even common Hymenopodid mantises. This is the reason why, rare and more beautiful species cannot be appreciated by us on par with their more common relatives. One such species is the Yellow Flower Mantis Parhymenopus davidsoni (Wood-Mason, 1890) found in highland rain forests of Thailand, Malaysia and Indonesia. During my field trip to Cameron Highlands, Malaysia I learnt that the forest dweling people of Semai tribe seldom find Yellow Flower Mantises on various plants that have inflorescences of fragrant light coloured flowers. It appears that the Yellow Flower Mantis is not so common on flowers frequented by a strikingly similar and more known species - the Orchid Mantis. However, Yellow Flower Mantises might be more common in the upper canopy to which insect catchers have no access. Early this year I got a comparatively small female which seemed to be strong and active. She started feeding actively and after 10 days laid her first oötheca (egg case). Soon followed by another two, each after an approximately two week interval. Each oötheca hatched after a 30 day incubation period giving birth in all to 164 nymphs. This was a perfect start for a captive colony of this species. Since time immemorial, people in different parts of the world were fascinated by the unusual behaviour of praying mantises. The most impressive behavioural act praying mantises perform is the startle display and theYellow Flower Mantis is no exception from the rule. Whenever a female encounters something dangerous like a frog, a gecko or even a small bird it may suddenly open its wings and fearlessly strike the intruder. Such a quick change of size and shape, topped with unexpected aggression makes predators leave the mantis alone. Yellow Flower Mantis males and nymphs are too small for such tactics and it is easier for them to fly or run away from danger. During early stages, Yellow Flower Mantises have other ways to avoid their enemies. Newly hatched nymphs are about 5.5 mm long, bright orange in colour and move fast. Most of the potential predators would hesitate to eat them because, to them, they look like distasteful and dangerous Assassin Bugs (Reduviidae). In addition, such young nymphs may set their forelegs into a pedaling movement the same way as certain species of Jumping Spiders (fam. Salticidae) move their palps. These spiders are voracious and quick predators feared by many larger insects. After the first moult Yellow Flower Mantis nymphs drastically change their appearance, they become yellow or light green in colour and a little bigger. These colours easily disguise them against most of the natural backgrounds and from then on Yellow Flower Mantis nymphs largely rely on camouflage to be unnoticed by predators and prey, spending endless hours absolutely motionless with their forelegs folded or stretched forward mimicking a young shoot or a flower bud. My experimental releases of Yellow Flower Mantis nymphs on various inflorescences show that they usually hide under flowers among the flower stalks. Such a position, makes them virtually invisible on this background, protects them from direct sunlight, and allows easy access to prey attracted by the flowers. This kind of insect behaviour is called floral simulation, and the question whether the plant benefits from it remains to be answered. In spite of their small size, the nymphs are typical
mantises in their eating habits, they catch and devour any moving object of appropriate size. Their usual diet includes bees, butterflies, flies, spiders, etc. and just like most insectivorous predators they avoid eating bugs and ants. To become adult, Yellow Flower Mantis female nymphs undergo eight moults, while males undergo only six. After each moult nymphs become a little bigger. In insects, the time between two moults is called an instar. Usually each subsequent instar is longer than the previous, thus the last instar of a Yellow Flower Mantis female nymph can be 6 times longer than one of the early instars. Male nymphs reach adulthood in about 2 months, while for female nymphs it may take twice longer. Adult Yellow Flower Mantises are easy to recognize since both sexes have well developed wings and are very good fliers. The species exhibits remarkable sexual dimorphism. Females are 1.5 times longer (up to 48 mm) and 10 times heavier than males, besides the coloration of two individuals of the opposite sex can be quite different. I observed that the female's main colour can range from brownish orange to yellowish white, while for males it ranges from light green to yellowish white. Males and females are ready to mate on the following day after becoming adult. Mating is not an easy task for males, because females very often eat them before or after it. In the wild, males locate females by smelling female pheromones. Once a female is visible, the male slowly approaches her from the rear and makes an attempt to climb her back. If the attempt is successful he establishes himself there and rubs her back with his forelegs, sometimes in a very rough manner. This back scratching helps the female to realize what's going on and makes her more cooperative. Females can mate more than once. Copulation may start at any time of the day and usually takes 3.5 hours. Sooner or later, after copulation, the male has to get down from the female's back and he must do it very carefully or he never makes it to another female. The life span of the Yellow Flower Mantises in captivity is approximately 3 months. I believe it can be twice longer in the wild, however a 3 month time span allows the female to lay 1-3 egg cases, while for the male there is enough time to mate with as many females as he wishes until he is eaten by one of them.
Some of the results obtained while breeding Parhymenopus davidsoni. In principal, each stage of their life should be longer than the previous and females' life stages are longer than the corresponding life stages of males. However in real life it may not allways be the case. Such factor like food consumption may influence even the number of instars it takes for a nymph to reach the adulthood.
