A PRELIMINARY INVENTORY AND COMPARISON STUDY OF TERMITES AT TWO DISTANT LOCATIONS IN MYSORE CITY - PART 1
Post date: Feb 20, 2018 10:14:59 AM
An effort made to understand the co-existence of termite population in two different locations under an aggravating urbanization is presented here. The result expresses Termite miscellany of two locations. Totally eight species have been documented of which four are present in Regional Museum of Natural History premises and seven in Roopa Nagar Residential Layout. The reason behind the absence of few species at two different locations is required to be ascertained in future studies.
The Regional Museum of Natural History (RMNH) is located in Mysore, Karnataka situated on the south-eastern part of Mysore City adjoining Karanji Lake. Spread over an area of 2 acres, RMNH premises houses a well-maintained garden supporting plants and grass to tree varieties. It supports diverse life forms - insects, mammals, reptiles, mollusks and rich in organic materials includes 26 butterfly and 32 bird species. Here symptoms of termite presence found seasonally. Since the museum has adopted “No Pesticides” policy, recorded a number of Termite trails in the natural cover on the garden flooring.
Roopa Nagara (RNRC) is a recently planned residential Colony sprawling about 100 hectares and on the western outskirts of Mysore city. The area studded with a scanty population of mango and coconut cultivation along with other native species of Ficus, Pongamia and Acacia converted into a planned residential colony. Predominantly this area is surrounding by numerous human settlements. This area does not have any open water bodies.
Method & Results
The RMNH, once a barren land with few thorny shrubs and clumps of grass had been converted into arable and varieties of plants have been planted in the past 22 years. As the maintenance and other activities produce heaps of organic wastes, it attracted a number of insect forms to dwell in. Thus termites also had an opportunity to hold their colonies.
Whereas, the RNRC is a human settlement, studded with numerous termite occupations and being transformed into a new gardening plot. The agricultural and horticulture fortifications are ably holding up the termite fauna.
Termite samples were collected from both the areas in different seasons of the year beginning with the year 2006 till 2014. Usually, samples were collected in the field just after sunrise when they are more active. The insects were picked up by using soft round brush (usually number 03 denomination) and put into vials containing 70% alcohol which is the best and time-tested preservative for these soft-bodied insects, and when collections made in a greater number i.e. from excavation of a mound, the lot was preserved in a cold box and later transferred in to alcohol preservative. On each collection prepared field notes with details like location, time, nature of the nest - mound/ bark/ underneath stone/dry dung; weather –sunny/rainy/ after rains etc..
Around 100 vials of termite samples were sent for taxonomic identification to Zoological Survey of India (ZSI), Kolkata. The report confirms identification. The termite samples have been deposited vide ZSI -55/2016 for future references and further studies.
Table: Termite species recorded in RMNH and RNRC
Brief description of Species
Termites construct three types of nests:
- Nests below ground level –underground / subterranean
- Mounds - above ground level
- Arboreal nests – on trees, high stumps ...
The higher termites (Termitidae) build terrestrial nests, above ground, which houses a large fungus garden, but there are subterranean nest builders too.
Each species have specialized a fastidious architectural pattern of nest building to suit its lifestyle, basically, the mound patterns may be classified into unilocular, where a nest has a large central cavity and in multilocular pattern several cavities. This is further divided into fungus growers and non-fungus growers.
The most common and important mound building termites in south India are;
- Odontotermes obesus (recorded in present study area)
- Odontotermes redemanni (not recorded in present study area)
- Odontotermes wallonensis (recorded in present study area)
Out of these, Odontotermes obesus build very tall and conspicuous subcylindrical mound, with series of buttress supporting the structure all around.
Further termites are recognized as larger species and smaller species based on the head length to the base of mandibles. If it is more than 2.0mm they are placed under larger species.
Outlines of genus Odontotermes and genus Trinervitermes, that are dealt in this article.
- Head: pale yellow-yellowish brown coloration; sparsely hairy head, and fairly densely hairy body
- Head-capsule: oval or subrectangular, converging in front.
- Fontanelle indistinct
- Antennae –with 15 -18 segments
- Labrum- Tongue shaped, anteriorly either rounded, at anterior margin or narrowed to a sharp or bluntly rounded tip
- Mandibles-delicate to strong and stout.
- Left mandible-with a small, rudimentary to a large and prominent tooth situated at variable positioned on inner margin.
- Right mandible – the presence of a small, rudimentary corresponding tooth.
- Postmentum –subrectangular, weakly to strongly arched, sides sub straight to strongly convex.
- Pronotum – saddle-shaped.
Genus: Trinervitermes – Soldier - Dimorphic: Soldier Major and Soldier Minor
1. Soldier Major
- Head – with along cylindrical rostrum narrowing towards anterior end.
- Antennae –with 12-14 segments
- Mandibles – vestigial without any spinous process.
- Pronotum – strongly saddle-shaped.
- Legs – moderately long, hairy.
- Abdomen –Elongated.
2. Soldier Minor resembles the major in many respects
- Head capsule elongated pyriform to subrectangular.
- Rostrum – narrow, cylindrical and much lengthier, compared to head length than in major.
- Antennae - 12-14 segments, longer in comparison to soldier major