Ants in RMNH campus, Mysore
PRELIMANARY STUDIES ON ANTS [ORDER HYMENOPTERA, FAMILY: FORMICIDAE] AND THEIR DIVERSITY AT THE REGIONAL MUSEUM OF NATURAL HISTORY CAMPUS AND ITS SURROUNDINGS, SIDDARTHA NAGARA, MYSORE – 570 011, SOUTH INDIA.
The Regional Museum of Natural History is located on the northern bank of legendary Karanji tank at Mysore and sprawling over 5.23 acres along the foot hill of Chamundi. The museum campus promotes the growth of 315 species of plants, which includes sixty-two species of major trees, eighty-five varieties of shrubs, creepers, herbs and seven species of grasses. Throughout the year, ideal and conducive weather for any living organism prevails. The adjacent Karanji tank  acres] provide food and shelter for about 56 species of aquatic and terrestrial birds. The Chamundi hill stands as the backdrop of museum, replenish the ground water to the study area. Thus, the Museum campus found to be an ideal natural setup for the natural inhabitation for many life forms. Considering the ecological connotation of ants as one of the very important agency that propagate a healthy environment and well support balance to other live form, the present study initiated. There is no previous attempt made in these aspects along the study area. Hence, the preliminary report of the attempted studies on ant fauna presented here as baseline works that may invite a detailed study in future.
DESCRIPTION OF THE STUDY AREA
The study area, Regional Museum of Natural History is located in Mysore at Karnataka state[India] is situated between 12º18” North latitude and 76º 42” East longitude at the North –western base of the Chamundi hill. The height of elevation is 2525ft MSL. The museum is located on the Northern bank of Karanji tank with the backdrop of Chamundi hill.
This garden houses diverse life forms such as insects, mammals, reptiles, birds, mollusks etc and rich in organic materials supporting various flora, trees to grass varieties. For example, there are twenty-six butterfly species, thirty-two species of birds etc., in this view a preliminary inventory of ants made, which yield an astonishing result on the ant miscellany of the campus.
The museum and its supplementary buildings occupy nearly about two acres of area that houses museum galleries, administration, technical, library, a minor kitchen, a transit accommodation, and stores.
In all such area one or the other type of ants found seasonally. Since museum has adopted “No Pesticides” policy, one can easily perceive a number of ant trails in the natural cover on the garden flooring.
The early enumerations by various scientific agencies lists out an approximate of three hundred and eighty ant species reside in. In Mysore city alone about, thirty-four species been counted at different biotypes. The biologically rich microhabitat RMNH campus is holding a very good carrying capacity of twenty-three species of ants belonging to five subfamilies of ants shown in table 1.
TABLE ONE - LIST OF ANTS
However, there is very little information in Kannada literature on ants available, there are several varieties identified by the village folk in their own way and such information exactly match the information of modern days. The ants classified into ten to twelve groups. The vernacular and synonym shown in table 2.
TABLE TWO – VERNACULAR AND SYNONYMS
Though there are many ants resemble each other, these names are more in usage in identifying the ants for the convenience.
SUBFAMILY: - DOLICHODERINAE
Scientific name: - Tapinoma melanocephalum [Fabricius]
Common name: - Odour Ant
Local name: - Vaasane Iruve
These ants are very small, they measure about 1.5 to 2 mm in length. The thorax and abdomen pale yellow coloured. The gaster is pale yellowish white in colour. At houses, usually in the kitchen they are trailing around sweet spillage and food items. They nest in the trees, at the base of the trunk, crevices and cracks in the buildings. Some times, they nest in the cloth folding, old news paper bundles also. They are fond of flower nectar and plant sap secretions; they can predate soft bodied and dead insects also.
In RMNH garden, they found trailing on the bark of Madhuka indica, Syzygium cumini, and Spathodea campanulata trees.
Scientific name: - Technomyrmex albipes [F.Smith, 1861]
Common name: - White - footed Ghost Ant
These are very common black shiny ants with white coloured tarsus. White footed ghost ants measure about 2.5 to 4 mm in length. In gardens one can easily notice, they are trailing in ling trails and feeding on nectaries. Apart from feeding on nectar, they tend homopterans for the honeydew. Usually they are arboreal by nature. They nest under stones, below leaf litter coverage, rotten barks, In RMNH garden they found nesting under the bark of Albezia lebbeck, Aegle mermelos trees
When compared the head is longer than the breadth, the antennal scape is moderately long, gradually thickening towards the apex of the funiculus. A very fine silky white hair covers the entire body, the gaster is oval and there are five gastral segments visible in the dorsal side.
In RMNH garden, these ants have seen on the Ixora sp, Jasmine sp, Pentas sp, Punica granatum, Tabernaemontana sp. Mussaendra sp, Balsam sp plants.
SUBFAMILY: - FORMICINAE
Scientific name: - Anoplolepis gracilipes [Smith, 1857]
Common name: - Yello Crazy Ant
Local name: - Oduga
These are very fast moving ants; hence, they called ODUGA in local dialect means RUNNER. With such fast movement, sometimes they appear moving helter – skelter in loose trails running crazy.
These ants measure about 6.5 to 7 mm in length. They are predators by nature and feed on wounded, weak insects, caterpillars and they feed on homopteran honeydew. Their diet includes chewing the sprouts and young shoots too. Their filliform antennae are 11 jointed. The scape of the antennae is long and can reach far above the head. The oval shaped, massive gaster is from pale yellow to dark brown in colour. The legs are extremely long and slender.
These ants nest in cool, shady and moist places under leaf litter at the base of trees and large shrubs. They are unarmed; their movement on the body causes tickling sense.
In RMNH garden, they nest at the base of Callistemon sp and Ficus benjamina trees.
Scientific name: - Paratrechina longicornis [Latreille]
Common name: - Black Crazy Ant
Local name: - Kari Oduga
These fast runners are quite familiar to every one. Usually they found around the kitchen, on the pavements, on the walls, at the wardrobes, bookshelves …
They measure about 3 to 3.5 mm in length. The long antennae 12 jointed and remarkably long and slender scape is an important identification key. Like the other craze ant, they too feed on sugary products and scavenge on dead /organic matter. The gaster is oval and huge. These ants are dull brown in colour, because of the minute hairs abundantly cover their body they look black. This is an unarmed species; they cannot bite or sting. They nest in pavement cracks, underneath stones, wood logs, and leaf litter in the gardens.
These ants found in RMNH garden as well as in vehicle garage, generator workshop, and vehicle-parking area.
Scientific name: - Polyrhachis lacteipennis [ Smith, 1858]
Common name: - Common Bullhorn Ant
Local name: -
Usually this genus is arboreal by nature, but this species found nesting at he base of Terminalia sp., trees. They construct carton nests.
This ant measure about 7.4 to 7.6 mm in length. They are black in colour; the three pairs of spines are important identification key. One long pair on the petiole curves to the shape of the gaster; one long pair on the propodeum with tips curved outwards; and the last pair, two short thick divergent spines on the anterior part of the pronotum. The long and sharp spines an the petiole resembles the horns of a bull. Hence, this ant called Bullhorn Ant. The gaster is opaque, short and oval.
Usually they seen underneath the trees and large shrubs, and may nest in corner of houses and other minor gardens. They diet on sugary secretions of plant sap, and scavenge.
In RMNH garden, they nest at the base of Terminalia tomentosa, Terminalia bellarica tree base and Corner of bird watching tower staircase, and in the scrap yard corners.
Scientific name: - Polyrhachis rastellata [ Latreille, 1802]
Common name: - Shiny Four - star Ant
These ants are also arboreal ants like their cousins. However, they may be nesting in other places also. They measure about 5 to 6.5 mm in length. Their body is black, smooth and shiny. The coxae, femora, tibiae of the leg display tinge o red colour. The head is triangular; the gaster is round – globose and shiny. There are four sharp radiating spines projecting upwards and raised pronotum. They have very few hairs distribution on the body.
They construct their nest by spinning a thin silky wed between two or three leaves. Some times in the corners with dull light in abandoned buildings , masonry work areas, they construct carton nest using pieces of dry leaves, wood scraps, jute fibers.
In RMNH, garden the nests found in an abandoned telegraph pole, in the electrical switch boxes, and in Duranta variegata plant.
Scientific name: - Camponotus irritans [Smith, 1857]
Common name: - Gaint Honey Ant
Local name: - Kempu godda
These are ground dwelling ants, they construct nest in soil, rarely in cracks and crevices in buildings and structures. They are polymorphic. The major worker ants measure about 8 to 10 mm in length and the minor worker measure upto 6 to 7 mm.
The mesosoma little longer compared with its cousins, in major workers the gaster is dark- reddish brown and shows shining. Where as in minor worker the head and mesosoma are honey coloured. The node of the petiole conical in shape, and little convex in anterior and posterior it is flat.
These ants are predators and scavenge on small insects, caterpillar, worms, egg deposits and organic matters.
In RMNH garden, one can notice them roaming with other ants on trees bark, walkways and underneath small bushy plants.
Scientific name: - Camponotus sericeus [Fabricius, 1798]
Common name: - Golden Back Ant
Local name: - Vibhuti Iruve
These ants show a distinct polymorphism. There are major, median and minor workers. The major worker measure about 8 to 10 mm in length. The minor worker measure about 3 to 4 mm.
The head and thorax is opaque black, gaster has a dense deposit of silky golden or silvery pubescence. The legs, antennae, tibiae, tarsi of the legs are darkish red in colour. Though the median workers resemble the major workers, they are smaller in size and the colour of the legs and antennae are lighter compare to the major workers.
Generally, the minors stay near / around the nest area. These ants build their nest with a circular entrance and the excavated debris deposited on one side of the nest.
Tandem behavior is a characteristic of these ants.
Scientific name: - Camponotus compressus [Fabricius, 1787]
Common name: - Godzilla ant.
Local name: - Godda, Kttiruve, Karigodda.
These are one of the biggest ants, robust built. They show a clear distinct polymorphism. One can easily notice the major workers and minor workers.
The workers have a massive, disproportionately large head and measure about 11 to 16 mm length, with strong mandibles. The minor workers measure about 6 to 8 mm in length they have a small head. The gaster is quite big they have frontally located eyes. Their bite is very strong, painful and mean time may bleed.
They are commonly congregating at urinals to feed on urea. They enter houses where they come in scores in search of food. In parks and gardens, they are a common scene. They are very good predators, they predate on smaller animals, insects, dead and decaying matter and even on their wounded companions.
Generally they nest under ground at the tree base , some times they gather in old abandoned plumbing pipes, toilet and sewage transporting pipelines, and under ground drainage chambers.
The major workers display tandem running.
In RMNH garden, they found near at almost all the trees moving individually and in small groups.
Scientific name: - Oecophylla smaragdina [ Fabricius, 1775]
Common name: - Weaver Ant
Local name: - Kenjiga
These well-known arboreal ants of India build nests on various trees and big shrubs. The nests are made of leaves, using silk produced by their larvae to join the leaves.
These ants also polymorphic, they are bright orange in colour, there are major, median and minor workers. The major worker measures about 8 to 10 mm.
These predatory ants equipped with strong triangular mandibles with the first tooth long which can grip any thing with ease. The narrow mesosoma gives the ant a slender appearance. They feed on other insects, larvae, including other ants including their own wounded companions also.
Though these ants construct their arboreal nests on a very wide range of trees and shrubs, usually they select Mango [Mangifera indica], Champaka [Michelia champaka], and Pongamia [Pongamia pinnata] trees.
The presence of these weaver ants regulates the invading monkeys, certain birds and insects to these trees. The bite and spray of these ants causes unbearable pain and burning and keep any intruder away.
In RMNH garden, they are found on seventy-seven species of plants belonging to thirty-four genera. A documentation of these plants and trees can be found here.
SUBFAMILY: - MYRMICINAE
Scientific name: - Cataulacus taprobanae [Smith F, 1853]
Common name: - Deceptive serrated Ant
These dull coloured ants are d\little difficult to find, they live in the nest built in hollows of trees. They well camouflage with the background of tree bark.
They measure about 4 to 4.5 mm in length. An important clue to identify them is, they play dead when disturbed. They have a broad flat head; the antennae protruded from the groove slit. The antennae are club shaped with 11 joints with three apical joint of the funiculus forming a club. The head and mesosoma irregularly striated, the gaster is oval, and propodial spines are directed towards the gaster and divergent. The head mesosoma and gaster have bristle like hairs. Legs are short and stout. The antennae, tibia and tarsus are yellowish red in colour.
These ants are solitary foragers; they tend aphids and feed on the excreted honeydew.
In RMNH garden, they found on Sphathodea companulata, Pongamia pinnata and Milletia ovalifolia trees.
Scientific name: - Crematogaster ransonneti [Mayr, 1868]
Common name: - The Glossy Slender Acrobat Ant.
Local name: - Cheliruve
These ants measure about 4 to 4.5 mm in length. Though they are arboreal dwellers, they found in underground nest sites also. The antennae are slender and the scape extended beyond the top of the head. The club of the funiculus formed of the apical the segments. These ants have an extremely broad cordate gaster; the heart shaped gaster is shiny black in colour. Generally, they are orange or dark brown in colour, there are no hairs on the body; the head is a square, the propodeal spines are long and little bit divergent.
When alarmed or in hurry they raise the gaster, for the reason they are compared with scorpion and called CHELIRUVE.
In RMNH garden, they found on Ficus benjamina, Syzygium cumini, and Morinda tinctoria trees.
Scientific name: - Crematogaster subnuda [Mayr, 1879 ]
Common name: - Common Broad Acrobat Ant
Local name: - Cheliruve
These ants measure about 3 to 3.5 mm. They are bright chest –nut red in colour and the gaster is nearly black in colour. They have slender antennae with long scape reaching beyond the top of head. The antennae are 12 segmented; the last three apical segments thicken to form a club. The pronotum is huge and rounded anteriorly mesonotum is small and sloping propodeum. The propodeal spines are short and pointed. The post petiole grooved longitudinally, like the other members of the genus; this ant also keeps the gaster upheld while foraging or alarmed.
They construct carton nests where there is a cup shaped accommodation available on tree body or at the branch intersections.
In RMNH garden, they found in the leaf pocket of Ficus krishnae tree, Samanea saman tree bark surface.
Scientific name: - Meranoplus bicolor [Guerin –Meneville, 1844]
Common name:-Silky Shield Ant
Local name: - Goorala
These ants measure 4 to 4.5 mm in length. The antennae are nine segmented and the apical three segments of the funiculus forms a club. The trapezoidal head deeply grooved, just above the eye to accommodate the antennae to fold and rest. The anterior portion of the mesosoma has short and acute angles, and posteriorly equipped with sharp, elongated backwardly pointed spines. The propodeum also armed with two backwardly pointing spines. These ants are ground dwellers; they construct their nest in the shade of small shrubs or in open fields where there is no vegetation.
They are too slow and sluggish in movement. When disturbed, they roll into a ball and play dead. The whole body is covered with very minute and long silky hair , thus compared with a person wrapped in a woolen rug moving in slow pace called GOORALA in kannada.
They feed on floral nectar, while feeding nectar they help pollination also. They harvest grass seeds also.
In RMNH garden, they found in TFL garden nursery and in front of scrap stores.
Scientific name: - Monomorium pharaonis [Linnaeus]
Common name: - Spineless Harvester Ant
Local name : - Hottiruve
These are small sized harvester ants. They display polymorphism. The major workers measure about 3 mm and the minor worker measure about 2 mm.
The entire body of the both caste is smooth and shiny. The body colour is reddish yellow and the posterior part of the gaster is black in colour. The colour of the head and mesosoma is slightly paler in minor workers. They have a slightly thick node of the petiole; it rounded at the top.
These ants go for foraging in long trails. They construct their nest in soil below leaf litter.
In RMNH garden, they are elsewhere.
Scientific name: - Myrmicaria brunnea [Saunders, 1842]
Common name: - Short –legged Hunchback Ant
Local name: - Gooniruve
These ants measure about 5.5 mm to 8 mm in length.
The antennae are seven jointed which is an important key in identifying this genus. The head and mesosoma are striated. The antennae and slender legs have oblique, reddish – yellowish bristles. These ants are chestnut red in colour and body full of shiny long straight bristle. The gaster is black in colour. The propodium armed with a pair of spines. They display a peculiar movement sign they keep the abdomen bent down while walking. Though they are scavengers by nature, they tend homopterans for honeydew. These ants build huge crater like nest in open ground / under the base of trees.
In RMNH garden, on the lawns one can notice them busy in excavating.
Scientific name: - Pheidole watsoni [ Forel, 1902.]
Common name: - Spiny Harvester Ant
Local name: - Hottiruve
These harvester ants are polymorphic. The major worker measure about 4 mm and the minor workers measure about 1.5 mm in length. The major workers have a massive, rectangular, longitudinally striated head disproportionate to the body. The mesosoma of the major worker is reddish brown the gaster is brownish. The leg and antennae shows yellow shade. The propodeal spines are short and erect. The post petiole portion is wider than the petiole.
The minor workers are pale yellow with darker head and brownish gaster. Body of these ants covered with short erect hairs. The major workers show tandem running.
In RMNH garden, they are nesting at the TFL garden and Scrape stores area.
Scientific name: - Solenopsis geminata [Fabricius, 1804]
Common name: - Common Red Fire Ant
Local name: - Kempiruve
These ants are polymorphic. The major workers measure upto 7 mm in length. The Minor workers measure about 3 to 4.5 mm. There is a slight colour difference among the worker castes.
The major workers are reddish yellow in colour; the mandibles and gaster are dark reddish brown. The head is disproportionately large and square shaped. The minor workers are pale yellow in colour and gaster is dark reddish brown. The antennae are with 10 –segments like all myrmicines.
Solenopsis geminata has a two-segmented waist and a gaster armed with a stinger. When they bite, it creates unbearable pain and burning like as if burnt by a red-hot iron.
They construct nest in soil with loose diffused soil particles raised all around above the ground with several entrance for a colony.
In RMNH garden, one can notice them at several points along with curbstones.
Scientific name: - Tetramoriun walshi [Forel, 1890.]
Common name: - Sluggish Wooly Ant
Local name: - Boodi Goorala
These ground dwelling sluggish ants measure about 2.5 to 3 mm. These tiny ants move in such away it is too difficult to notice their presence. The antennae are short and 12 – segmented. The last three apical segments form the club of the funiculus. The propodeum has a pair of short backwardly pointed spines. The gaster is oval, the petiole and the post petiole are longer than the breadth. Though the mandibles, legs and antennae are yellowish brown, the dense whitish hair all over their body gives them an ashy look. They construct nest with a raised opening amid the grass culms.
In RMNH garden in the model forest area, they have the nests in rubbles and leaf litter deposit.
SUBFAMILY: - PONERINAE
Scientific name: - Diacamma ceylonense [Emery]
Common name: - Greater Straited Bispinous Ant
Local name: -
These strongly built, black ants measure about 12 m to 15 mm in length. They are usually solitary foragers. They have a pair of curved spines on their petiole, pointing towards the gaster. The whole body covered with velvet like grayish pubescence. Antennae are long. These ants are predatory by nature; they feed on several insects including other ants and alate insects.
Their nest construction is quite interesting. The nest entrance decorated with small twigs, stones, and with small plumages of birds in a circular pattern.
In RMNH garden, they had their nest at the model forest site.
Scientific name: - Leptogenys processionalis [Jordon, 1851]
Common name: - Procession Ant
Local name: - Saaliruve
These workers measure about 8 to 10 mm in length. Some times these are confused with the blind ants.
These ants have powerful and sharp mandibles. The head is oval, the upper surface of the petiole is compressed and is narrow above conically. These reddish brown ants can deliver a painful sting. In long trails, they go for forage. Hence, they called “processionalis”.
These ants are nomadic by nature; they keep on shifting their sites. They have a good tendency of foraging and hunting. They even can hunt animals quite bigger than them in many folds. Such as centipedes, frogs, toads, worms, coleopterans etc.
In RMNH garden, one can see them on set of monsoon in long trails at many places.
Scientific name: - Platythyrea sagei [Forel, 1900.]
Common name: - Shy spineless Bark Ant
These arboreal ants measure about 7 mm in length.
The antennae are thick and cylindrical, the mandibles and legs are reddish brown in colour. The body is opaque black. The petiole has a tooth on either side that is pointing outwards and backwards. Interestingly the propodeum too has a tooth like structures on each side, which points backwards and outwards.
The shape of their petiole and propodeum can easily identify these ants. They nest in cracks and crevices in trees. Usually they forage on the trunks of Mangos, Banyan, Fig, Bauhinia, Thespesia trees
SUBFAMILY: - PSEUDOMYRMICINAE
Scientific name: - Tetraponera allaborans [Walker, 1859]
Common name: - Polished Leaf- border Ant
These extremely shining arboreal ants measure about 5 to 6 mm in length.
Their antennae and mandibles are reddish yellow tinge. The legs are reddish brown and the femur is blackish brown in colour. The head is rectangular, the propodeum more or less equalizing the height of pronotum and mesonotum and placed in the same plane. The conical post petiole is broader than the oval petiole. They have large and oval eyes. There is scanty distribution of hair on the body.
Usually they found nesting on trees, their nests found in the cracks and crevices and in hollow of tree branches. These predator ants feed on a variety of diet. They forage on the bark and on the leaf borders and edges. They kill the prey by their sting and bring their catch to the nest
In RMNH garden, they usually found on Bauhinia trees.
Scientific name: - Tetraponera rufonigra
Common name: - Arboreal Bicolored Ant
These territorial and aggressive ants usually found foraging on tree bark crevices and cracks. They are arboreal by nature.
The colour of the body, size and shape is characteristic and helpful in identification. These ants measure about 10.5 to 13 mm in length. The antennae, mandibles and mesosoma are red/ orange; the head, post petiole and gaster are black. The red colour may vary and match the different degrees of red tinge, like light orange red, orange yellow, brick red. The head is rectangular, it is larger than wide. They have three ocelli; the legs are moderately stout and large. If they are provoked, immediately they sting. The sting is quite painful.
They nest in the deadwood, wooden stumps and beams. In RMNH garden, they found on the Rain trees [Samania saman].
About the author
Mr S. J. Srinivasa is a sculptor by profession, but by passion, he is an amateur naturalist. He had an opportunity to take part in a one day workshop on 'Ant study' arranged by Mysore Amateur Naturalists (MAN), Mysore in the year 2004, under the guidance of Mr Sunil Kumar M. Later who authored a handbook on the ants of peninsular India 'On a Trail with Ants' co-authored by Ajay Narendra. This participation leads Mr S. J. S. to study the ant fauna at his working place. He pursued the study with available materials and means since 2004 and in July 2010 he compiled his findings In the Regional Museum of Natural History (RMNH), Mysore. He is highly grateful to MAN and Merlin Nature Club, Bangalore who provide literature and support.