H. bicornis (Stoll)
Hymenopus coronatus, also called H. bicornis, is a mantis from the tropical forests of Southeast Asia. It is known by various common names including walking flower mantis and (pink) orchid mantis. It is one of several species known as flower mantises from their resemblance and behaviour.
This species is characterized by brilliant colouring and a structure finely adapted for camouflage, mimicking parts of the orchid flower. The four walking legs resemble flower petals, and the toothed front pair is used as in other mantises for grasping prey.
H. coronatus shows some of the most pronounced size sexual dimorphism of any species of mantis; males can be less than half the size of females. The female predatory selection is the likely driving force behind the development of the extreme sexual size dimorphism. Prior to development of its camouflage, the female mantis implements ambush predation to allow it to hunt larger pollinating insects. An example of this ambush predation is the orchid mantis's ability to ambush foraging butterflies, a fairly large prey, which it captures using its pair of toothed arms and powerful bite. As the female orchid continues to develop, much of its dramatic increase in size can be attributed to predatory selection and ambush predation.
Hugh Cott quotes an account by Nelson Annandale of Hymenopus coronatus which he reports hunts on the flowers of the "Straits Rhododendron", Melastoma polyanthum. The nymph has what Cott calls "Special Alluring Coloration", where the animal itself is the "decoy". The insect is pink and white, with flattened limbs with "that semi-opalescent, semi-crystalline appearance that is caused in flower-petals by a purely structural arrangement of liquid globules or empty cells". The mantis climbs up and down the twigs of the plant until it finds one that has flowers. It holds on to these with the claws of its two rearmost pairs of legs. It then sways from side to side, and soon various small flies land on and around it, attracted by the small black spot on the end of its abdomen which resembles a fly. When a larger Dipteran fly, as big as a house fly, landed nearby, the mantis at once seized and ate it.
The species is reported by Costa, quoting Shelford's 1903 account, to show parental care by guarding the eggs. Costa asks rhetorically "Why has so little [research] been done on parental care in mantids, such an unexpected and intriguing aspect of their behavior?"
The species is carnivorous, mainly catching other insects. In the laboratory, it prefers lepidopteran prey. Its diet consists of small insects, including crickets, flies, fruit flies, beetles, and stinging insects such as bees. Some are cannibalistic, eating their own siblings when one strays too close.
In human culture
A beautiful drawing of this rare insect, Hymenopus bicornis (in the nymph or active pupa state), was kindly sent me by Mr. Wood-Mason, Curator of the Indian Museum at Calcutta. A species, very similar to it, inhabits Java, where it is said to resemble a pink orchid. Other Mantidae, of the genus Gongylus, have the anterior part of the thorax dilated and coloured either white, pink, or purple; and they so closely resemble flowers that, according to Mr. Wood-Mason, one of them, having a bright violet-blue prothoracic shield, was found in Pegu by a botanist, and was for a moment mistaken by him for a flower. See Proc. Ent. Soc. Lond., 1878, p. liii.— Alfred Russel Wallace
The drawing was published in Edward Bagnall Poulton's book The Colours of Animals. Poulton calls it an "Indian Mantis" which "feeds upon other insects, which it attracts by its flower-like shape and pink colour. The apparent petals are the flattened legs of the insect."
The orchid mantis is favoured by insect breeders, but is extremely rare, so is also extremely expensive.
- Gullan, PJ; Cranston, PS (2010). The Insects: An Outline of Entomology. Wiley (4th edition). Page 370.
- Prete, 1999. p.107.
- Svenson, Gavin J.; Brannoch, Sydney K.; Rodrigues, Henrique M.; O’Hanlon, James C.; Wieland, Frank (December 2016). "Selection for predation, not female fecundity, explains sexual size dimorphism in the orchid mantises". Scientific Reports. 6 (1): 37753. Bibcode:2016NatSR...637753S. doi:10.1038/srep37753. ISSN 2045-2322. PMID 27905469.
- Chen, Gao; Zhao, Guang‐Hui (February 2020). "Orchid mantis ambushes foraging butterflies". Frontiers in Ecology and the Environment. 18 (1): 12. doi:10.1002/fee.2155. ISSN 1540-9295.
- Gurney (1951). "Praying Mantids". Annual Report of the Board of Regents of the Smithsonian Institution. The Smithsonian Institution. 105: 344–345.
- Prete, 1999. pp. 283–184.
- DK Pocket Eyewitness Insects. Dorling Kindersley. 2012. p. 38.
- Cott, 1940. pp 392–393.
- Annandale, Nelson (1900). "Notes on the Habits and natural Surroundings of Insects made during the 'Skeat Expedition' to the Malay Peninsula, 1899-1900". Proceedings of the Zoological Society of London: 837–868.
- Costa, James T (2006). The Other Insect Societies. Harvard University Press. pp. 138–139.
- Shelford, R (1903). "Bionomical notes on some Bornean mantids". Zoologist. 4: 298–304.
- Boucher, Douglas H (1988). The Biology of Mutualism: Ecology and Evolution. Oxford University Press. p. 207.
- Prete, 1999. p.313.
- "Hymenopus Coronatus (Orchid mantis) Caresheet". InsectStore. 25 January 2006. Retrieved 5 January 2013.
- Wallace, 1889. Note 80.
- Poulton, 1890. pp 74–75.
- Cott, Hugh Bamford (1940). Adaptive Coloration in Animals. London: Methuen.
- Poulton, Edward Bagnall (1890). The Colours of Animals: Their Meaning and Use, Especially Considered in the Case of Insects. Kegan Paul, Trench, Trübner. pp. 74–75.
- Prete, Frederick R (1999). The Praying Mantids. JHU Press. p. 313.
- Wallace, Alfred Russel (1889). (Wikisource)