A group of jumping spiders that mostly occur in Eurasia and Africa, has been spotted for the first time in Ernakulam’s Illithodu forests by arachnologists from Kochi’s Sacred Heart College, Thevara. The team also found that the spider belonging to the genus (a taxonomic classification above species) Habrocestum is a species new to science.
The team came across the different-looking spiders — six of them, predominantly brownish-black in colour with white and creamy-yellow patches — while conducting a routine survey (funded by the Department of Science and Technology-Science and Engineering Research Board) for ground-dwelling spiders in the Illithodu reserve forests of the Malayatoor forest division, barely 60 km from here. Back in their laboratory, they examined the physical features of males and females. They also compared these to similar-looking spider specimens collected earlier from the Thattekkad Bird Sanctuary.
A detailed examination of the spiders’ physical features revealed that they belong to the genus Habrocestum that has been recorded mostly in Eurasia and Africa and never in India, till now. Comparisons with studies of European Habrocestum spiders revealed that the spiders from Illithode are a new species altogether, for they had distinctly different reproductive organs.
The spider also has a single long spine on the underside of both its first legs, and this gave it its scientific name Habrocestumlongispinum (after Latin ‘ longe’ meaning long and ‘ spinae ’ for spine). “It measures just around 2 mm and seems to prefer dry habitats, dwelling in forest litter,” said Mathew M. Joseph, assistant professor at Sacred Heart College and a co-author of the study published in the Journal of Natural History last month.
While more detailed ecological studies are required, threats could include unregulated tourism activities and even climate change (which could affect the small insects by altering the specific micro-climates that they prefer), he said.
The study extends the range of these spiders to India. The discovery also lends support to the continental drift theory that suggests that the world’s continents were one large, contiguous landmass where these creatures thrived many millions of years ago, added Dr. Joseph.
