The vast campus of Calicut University is a haven for a large diversity of jumping spiders, according to a recent study.
A ten-month-long study conducted on the lush green campus found 46 species of jumping spiders coming under 33 genera. It is for the first time in the country that the presence of such a variety of jumping spiders was detected from a particular area, say scientists.
According to them, spider diversity and density are directly related to the structural complexity of the environment. Highly varied habitats provide a greater array of microhabitats, microclimatic features, alternative food sources, and retreat sites, all of which encourage colonisation and establishment of spiders.
The study was conducted by Athira Jose, research scholar in Zoology under the leadership of E. Pushpalatha, Head of the Zoology Department, University of Calicut, and Dr. Sudhikumar A.V., Centre for Animal Taxonomy and Ecology (CATE), Christ College, Irinjalakuda.
This study was funded by the University Grants Commission (UGC) as Maulana Azad National Fellowship (MANF) to Athira for the project entitled ‘DNA barcoding of jumping spiders of Kerala’. Findings of this study appeared in the latest volume of Serket, an international scientific journal published from Egypt.
Eight eyes
These non-web builders usually capture their prey by a sudden jump over it, so these are known as jumping spiders. These spiders possess eight eyes in three rows. The last pair is located on the back of their head that enables vision of back side without having to turn their head. The big pair of eyes at the central position of the first row helps recognise these spiders in the field. These eyes help them to judge the distance to prey and also facilitate accurate jump. Its exceptional eyesight enables it to prowl round the clock.
Body of male individuals possess attractive colour pattern. They attract females for mating by their specific dancing act by the characteristic movement of legs and abdomen, which is known as nuptial dance. Since many members of the family mimic venomous wasps, it is very helpful to escape from enemies. Family Salticidae is the biggest spider family in diversity and there are 6,175 varieties of jumping spiders under 644 genera so far reported from all over the world.
The study was conducted in 500 acres of Calicut University campus, which is rich in acacia trees, teak plantation, mango orchard, scrub jungles, and grass lands. The study reported the presence of a pirate spider named Portia (moustached spider), which intrude into the web of other spiders and feed on the owner of the web. Muticoloured peacock spider (Chrysilla), minute dark jumper (Harmochirus), crescented spider (Hasarius), scorpion spider (Indopadilla), red ant mimicking spider(Myrmaplata), red-eyed spider (Phidippus), fly catcher (Plexippus), fly-mimicking spider (Phintella), yellow wasp spider(Rhene), and rusty headed spider (Tamigalesus) are the other important species reported from the campus during this study, according to Dr. Sudhikumar.
