Manjunath S Nayak:
When we were young, it was very difficult for the family to handle our pranks. To control us, they would threaten us by telling us ghost stories, showing pictures of leopards and other wildlife. If little ones resisted eating, they would threaten you with the fact that these animals would eat you up. But this led us to observe and study various types of species existing in the nature, specially spiders.
In the background of this, I along with Prakash Ganiger, Beat Forester and Sangamesh Kadagad a biodiversity researcher has discovered a trapdoor spider species in the forest beat of Shantageri village in Gajendragad taluk of Gadag district, Karnataka, India.
The size of the trapdoor spider ranges from 1.5 to 2 inches. A rare spider of the genus Tigidia belonging to the Barychelidae family, it was found in Shantageri village. These species are mostly found in Western Ghats and in the semi-Malnad areas. Their habitat is found on the roadside and on steep slopes of forested hills.
KNOWN FOR TUBULAR NESTS
The above picture is of Shantageri village where this species was found. The trapdoor spiders build tubular nests and live in nests. The nests have a beautiful circular lid. The name Nelagumma (in Kannada) is derived from the hair on its body and the way it hunts, and the name Nelagumma is derived from its characteristics of hiding in a ground burrow.
The trapdoor spider mate at night. Further, these spiders delicately hunt frogs, lizards, mice, small birds and insects. Since these spiders’ bodies are larger than other spiders, it is difficult to flee to distant areas except to hide in the nest when danger arises and escape the alternative route. When a minor problem arises, they straighten their hair and make special noises.
THREAT TO TRAPDOOR SPIDERS
If the above habitat is maintained, then there will be no threat to these spiders. However, rampant deforestation, habitat destruction, and rising construction of two-lane and four-lane roads are detrimental to this species of spiders. It is also believed that killing this spider can cure certain diseases. So, a sick person is placed in front of it and worshipped – believing, it will cure a disease.
In some areas, in order to overcome the monthly difficulties in menstruating girls, the nelagumma/nelakiriba is held alive, inserted in an amulet and tied around the neck of the girl child. These are all superstitious beliefs. Others kill it if they think it is venomous.
ENDEMIC TO WESTERN GHATS
In fact, there are seven species of Tigidia. Primarily found in the Western Ghats, some species have extended their range to other parts of India. Three new species were initially discovered in the Western Ghats and they are:
T. sahyadri
T. nilgiriensis
T. rutilofronis.
Later, T. konkanensis was found in the Konkan region of Maharashtra, and three more species, T. jalgaonensis, T. tangerina, and T. fasciata, were described, extending the genus’s known distribution in India.
The majority of Tigidia species in India are found in the Western Ghats which is one of the World’s Eight “Hottest Hotspot” for biodiversity.
MAINTAINING ECOLOGICAL BALANCE
Since the spiders of the trapdoor species form a hollow-shaped nest, rainwater through these trenches helps in entering the ground water naturally. Apart from this, the trapdoor spiders maintain ecological balance – controlling pests by feeding on insects that are harmful to farmers and pests to forest trees.
In view of this, it is necessary to create awareness among the public about the importance of spiders and other insects so that ecological balance on Planet Earth is maintained.
(PHOTO CREDIT: ALL IMAGES BY PRAKASH GANIGER, BEAT FORESTER, KARNATAKA FOREST DEPARTMENT)