Three new spider species identified from Western Ghats of Karnataka

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Adding more to the endemic fauna of the Western Ghats, researchers have identified and described three new species of spiders from the Uttara Kannada district in the Indian state of Karnataka. 

Neoheterophrictus crurofulvus (Male)

Christened as Neoheterophrictus crurofulvus, N. sahyadri and N. uttarakannada, the newly identified spiders belong to a new genus Neoheterophrictus which is close to the existing Heterophrictus genus of spiders.

 

According to a research paper published in the Journal of Threatened Taxa, certain morphological and anatomical features which were consistent with the three species makes them different from other members of the Heterophrictus genus. 

The spiders in the new species have multi-lobed spermatheca (an organ in the reproductive tract in female spiders and other insects which usually stores the sperm from males to help fertilization), says the paper. 

Despite their close similarities with members of Heterophrictus and Plesiophrictus genuses, male spiders of new species have double tibial spur or two additional spines or segments at the distal end of their limbs than the members of closely related genuses. 

According to  Manju Siliwal, who was part of the research team, Stridulatory spines in these spiders are located on outer side of maxillae (small leg like structure in front of legs, where the basal segment is called maxillae) and inner side of coxa of first pair of leg. "So for sure, sound producing (by these spiders) might be different", she said.

The African Connection

The newly found genus also adds to the Gondwana relic taxa of the Peninsula. "The new genus belongs to the subfamily Eumenophorinae, which is restricted to Africa in distribution. So, finding a genus or species that is having ancestors in Africa are referred to be Gondwana relic", said the researcher.Presence of such connections supports the theory that India, Africa, Australia, South America and Antarctica were part of the super continent Gondwanaland which later broke apart to form the present continents.
 

Female of Neoheterophrictus sahyadri

Among the three, Neoheterophrictus crurofulvus was named so for the light brown legs of the female spiders. ‘Cruro’ in Latin means legs or limbs and ‘fulvus’  means tawny or yellowish-brown. While the males of the species were found under decaying logs and rocks, females were spotted in burrows. According to the researchers, the females of the newly identified spiders make 0.15 to 0.25 meters long silky vertical burrows of 15 to 25 mm diameter on slopes.


"We found many male individuals below decaying wooden log and found one wandering female, first", said a researcher of the team. However, the female spiders gave a tough task to the researchers. " On searching for five months we were able to locate more females because they don’t built typical theraphosid web", says the researchers. 

Neoheterophrictus sahyadri was named after the biodiversity hot spot and world heritage site Western Ghats from where it was found, since the mountain ranges are called ‘Sahyadri’ in local languages. 

Female of Neoheterophrictus uttarakannada

Females of the N. sahyadri makes burrows of 30 cm deep under decaying logs or rocks and hides in the burrow if the log is disturbed. According to researchers, they also tend to mark the borders of the resting place with mud. 

The third among the newly described spiders was named Neoheterophrictus uttarakannada after the district from which it was collected. The new discovery adds to the arachinid diversity of Western Ghats. 

The new addition to points to the unexplored nature of the rich biodiversity of Western Ghats. "It shows that these areas have still potential to find something new or interesting.", said Manju Siliwal who is a researcher with the Wildlife Information Liaison Development Society, Tamil Nadu. 

Neha Gupta, University School of Environmental Management, Guru Gobind Indraprastha University, and Robert Raven, Queensland Museum, Queensland, Australia have also co-authored the paper.

Cryptothela Sundaica, a rare spider spotted after 122 years from India

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After a gap of some 122 years, a rare spider has been reportedly spotted from India since it was first recorded by a British Spider Researcher in 1890. 

Cryptothela Sundaica
Image Copy Right Sudhikumar

According to A V Sudhikumar, an Arachnologist with the Zoology Department of Christ College Irinjalakkuda in the South Indian state of Kerala, his team has found the rare spider Cryptothela Sundaica, from the forest patches of Thommankuthu waterfall near Thodupuzha in Idukki district.

The spider was earlier reported by British Archnologist R F Pocock in 1890s from Udagamandalam in the neighboring state of Tamil Nadu. Interestingly, the earlier report was about a male member of the species while the new record is about a female one. 

A Cryptic spider

According to Sudhikumar, the genus is called ‘Cryptothela’, for their cryptic nature which always hides them from the eyes of the researchers. The spider, with the size of a small beetle, according to the researcher, is mud coloured and is difficult to distinguish from the surroundings since it is often found amidst dead and decaying leaves. 

However, the researchers were lucky this time since the spider they have spotted at Thommankuthu was a female carrying a triangular, white egg sac over her. 

Living on a diet of worms and insects, Cryptothela Sundaica has many tricks to avoid attackers. “If disturbed, it exhibits catalepsy (acting like dead when disturbed)”, says Sudhikumar. 

According to the researcher, the finding may be shortly published at the journal of Journal of Arachnology published by American Arachnological Society. 

The new spotting is very important as organisms not recorded for a period of 100 years are usually considered extinct. However, there are hardly any scientific studies conducted on the species in the recent past. 

According to Wikipedia, Cryptothele is a genus of spiders which comes under Zodariidae family of spiders. Cryptothele has ten described species of spiders including Cryptothela Sundaica. It also shows that the species was also reported by Tamerlan Thorell from Singapore in 1890s and has two sub species.

Spider Diversity in India

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Believe it or not, these eight legged creatures comprise the largest order of animals in the animal kingdom. As with other micro fauna, the Indian subcontinent is rich with spider diversity too. According to an updated check list in 2012 India has1685 spider species from 438 genera and 60 families . Among this, 91 species are Mygalomorphs or spiders with their fangs pointed down without crossing each other, as in other group of spiders.  The remaining 1595species belong to Araneomorphs, or spiders with fangs which are opposite in direction, crossing over to each other.

According to research reports, out of the total spider species found in India, 70 are exclusively from Karakorum area, or in other words, endemic to Karakorum area.

Critically Endangered Spiders of India

According to International Union for Conservation of Nature (IUCN) the international agency which monitors the conservation status of organisms,If the population decline is severe among a species which wipes away almost 90 percent of the population in a decade, that species can be considered as critically endangered.

 IUCN also suggest that if the extent of occurrence of the organism shrinks to 100 km² area, or to a single location, it can be listed as critically endangered, indicating that it is closer to a possible extinction or a state where it no more exist in the face of the mother earth. If only less than 250 mature members of the species are known to exist, it also indicate that a species is critically endangered.

The Rameswaram Ornamental Spider (Poecilotheria hanumavilasumica)

Also known as the Rameswaram Parachute Spider, this beautiful organism is facing the risk of a possible extinction from the face of earth. This special spider has been so far found only from India, with the last record being from 2004.

The Rameswaram Ornamental Spider

These spiders are found to be semi-social which makes them live some time in groups or alone. These shy creatures tend to live in hiding and are found along the coastal savannah, tropical lowland rain forests and montane forests. They have been reported from altitudes up to 2000 m above mean sea level.

These spiders are dangerous with their ability to deliver quick poisonous bites. But their bits are not fatal in nature. However, they are finding their population falling down with their typical habitats being altered and degraded due to human intervention.

Present conservation status

According to IUCN, Rameswaram Parachute Spiders are restricted to a Rameswaram Island and the associated mainland close to the island, limiting its presence to a 100 km² area. However, based on the reports of occurrence, the actual area of occurrence of these rare species of spiders can be less than 6 km² area. IUCN documents claim that they are found on tamarind, casuarina and mixed dry deciduous tree and palm plantations here.

 Apart from the island, the species has been recorded from less than 15 severely fragmented locations also.

The alteration of habitat is the major threat to these spiders as their distribution is restricted. For instance, when the tamarind plantation sprawling to 5 hectares were recently grazed down by government authorities to build up government quarters, it killed all the 70 individuals found in the plantation. The flood o tourists and the associated construction activities are again sweeping away the remaining population of this rare spider.

Due to the loss of natural vegetation, continuing decline in area and absence of enough mature individuals may soon make this rare creature to vanish from the face of earth. Unfortunately, the legal machinery in India is yet o make any move to save this spider.

 The Gooty Tarantula (Poecilotheria metallica)

Also known as Peacock Parachute Spider, this magnificent creature is also facing risk of extinction in Indian subcontinent to which it is endemic. With a visually appealing steel blue color and patches of intense orange-yellow, black and white, it is also a victim of international pet trading rackets which smuggle them beyond borders to sell.

Reported from Gooty (Ooty/Udagamandalam) and from forests between Nandyal and Giddalur in the state of Andhra Pradesh in South India, it is also believed to have an area of occurrence of less than 100 km².

While habitat loss and degradation are the major threats to this spider which is known to live in deciduous forests, international pet trade rackets are the second major threat to these small beautiful creatures. IUCN has issued a warning that at the present rate, the species may disappear from earth in the near future.