Lethocerus indicus

Lethocerus indicusis agiant water bugin the familyBelostomatidae, native toSouthandSoutheast Asia, as well as southeast China, theRyukyu Islands, andNew Guinea.It was originally described asBelostoma indicumbut is no longer placed in that genus.
This insect is well known as an edible species in a number of different Southeast Asian cuisines. The taste of the flight muscles is often compared to sweet scallops or shrimp.
The Asian region has several species of Belostomatidae includingL. patruelis,L. insulanus,L. indicus, andKirkaldyia deyrolli.L. indicustypically has a length between 6.5 and 8 cm (2.6 and 3.1 in).Lethocerus insulanusis found along the islands of Southeast Asia to northern Australia and has a medial dark stripe between the light stripes of the pronotum whilepatruelis(found from southern Europe to Myanmar) has narrower light stripes and the first tarsomere on the foreleg is longer than the claw (almost equal inL. indicus).Kirkaldyia deyrolliis paler and lacks pronotal stripes. The genusKirkaldyiacan be distinguished fromLethocerusby more widely separated eyes, and the presence of two asymmetrical furrows on the inner setal pad of the fore femur.
The species is distributed widely in peninsular India, Sri Lanka, Bangladesh, into Southeast Asia, extending east to Taiwan and south along Sumatra, Java, Indonesia, Philippines and parts of western Papua New Guinea.
Glands in the abdomen produce odorous chemicals that include (E)-2-hexenyl acetate, (E)-2-hexenyl butanoate, 1-undecen-3-one, 3-mercaptohexyl acetate, and 3-mercapto-1-hexanol which may have a role as an attractant particularly in males. The first two are said to impart a sweet banana-like smell.
The large size of this insect and itsflightmuscles and the ease of dissection makes it an excellent model organism for muscle structure with special features pertinent to thecardiac muscle. The high degree of structural order makes is possible to obtainX-ray diffractionpatterns richer and more detailed than those from vertebratestriated muscle.
The Vietnamese call this insectcà cuống. It is a highly prized food and often boiled and fried whole.
The insect's essence (apheromoneproduced by the male that attracts females) is harvested by collecting its liquid-producing sacs. That liquid is then placed in small glass containers. The insect is claimed to be scarce,and demand for the extract is high. Most of thecà cuốngessence on the market is therefore imitation, with the actual essence fetching a high price.Cà cuốngis typically used sparsely and eaten withbánh cuốn(rice noodle rolls) by adding a drop to thenước chấm(dipping sauce).
It is also eaten in a soup dish called 'bún thang' adding a unique essence to the broth. The dish traditionally includes rice noodles, thinly sliced egg crepe, pork cold cuts, and other various additions in a chicken/dry squid broth. A tiny drop of the extract on the tip of a toothpick would suffice to flavor the whole bowl of soup. This dish originated in Northern Vietnam.
In the northeast region ofThailand, eating insects is common. In other parts of Thailand, including the Central and Southern regions, the aromatic essence from this species of insect, known asmaeng da(Thai:แมงดา),maeng da na(แมงดานา) ormaeng da na(แมงดานา), is also popular. The water bug can be eaten whole and fried, and as an extract.Maeng dais used to makenam phrikmaeng Da, a type of chili sauce used as a condiment.
In theIlocosregion in the northern part (Luzon) of thePhilippinessome insects such as crickets, locusts, and beetles are traditionally eaten. The water bug or water beetle is known asalukapinIlokano language. It is sauteed or fried in oil, garlic, onions and tomatoes, or roasted, after the wings and legs have been removed, and eaten as a viand for steamed rice or as a finger food with liquor. The same is done in theVisayasregion where it is calledobusin theVisayan language.
Consumption of *Lethocerus indicus* is valued for its nutritional benefits, including high protein content, and forms part of a broader cultural practice of entomophagy in the region. The insect is called *Gangjema* locally in some communities, and its preparation methods vary, but it is often fried or made into a savory dish.
In addition to Assam and Manipur, tribes in Nagaland and Mizoram also consume other edible insects, often prepared based on traditional culinary practices.