A pioneering study on the spider fauna (Arachnida: Araneae) of Sagar District, Madhya Pradesh, India

: The present investigations were carried out to elucidate the spider fauna of the Sagar district of Madhya Pradesh. A total of 1,505 spider specimens were documented from various sites of the study area. A total of 74 species grouped under 58 genera and 22 families are reported. The family Araneidae was the most common, accounting for 31% of the overall population followed by Salticidae, which accounted for 15% of the overall population. Spiders belonging to seven guild structures were identified which were then classified on the basis of their dietary habits. Further research is needed to analyze the behavior, biology and web patterns of these ubiquitous creatures.


INTRODUCTION
Spiders are remarkable primitive arthropods of the class Arachnida that live in every ecosystem on the planet, from Arctic islands to dry desert regions (Foelix 2011). They are members of the order Araneae, which are commonly known as spiders. Spiders can play an essential role in managing the populations of terrestrial arthropods. Because of their small body size, quick reproduction period, and great sensitivity to temperature and moisture changes, they are good biological monitors of ecosystem changes and habitat adjustments (Napiórkowska et al. 2021). Spiders are not only ecologically significant, but also commercially beneficial (Koneri & Nangoy 2017). Spider silk and venom have become essential industrial commodities, particularly in the pharmaceutical industry. They are also beneficial in decreasing the negative effects of pesticide and insecticide overdoses (Jose et al. 2018).
British explorers began studying spiders in India in the latter half of the 19 th century and taxonomists from India carried on the work (Siliwal et al. 2005). Presently, about 50,040 spider species classified into 4,250 genera and 131 families are described worldwide (WSC 2022) and India has 1,904 spider species classified under 490 genera and 60 families (Caleb & Sankaran 2022). The spider fauna of Madhya Pradesh was studied by various workers beginning from Tikader (1980Tikader ( , 1982a, Tikader & Malhotra (1980), and Gajbe (1987Gajbe ( -2003 in which they described several species from the families Thomisidae, Philodromidae, Lycosidae, Araneidae, and Gnaphosidae. Patil et al. (2013Patil et al. ( , 2016 studied spiders from Rani Veerangana Durgawati Wildlife Sanctuary and from the Nauradehi Wildlife Sanctuary, respectively. However, there is no information available so far on the spider fauna of Sagar district in Madhya Pradesh and thus the present work was carried out.

Study area
Sagar district is located in the north central region of Madhya Pradesh and covers an area of 10,252 km 2 . It lies between 23.16-24.45 °N & 78.06-79.35 °E ( Figure  1). The major part of the district is enclosed by the Deccan trap lava flows and Vindhayan sandstones in the eastern region (Pareta & Pareta 2013). The climate is quite harsh, with maximum temperatures of 45 0 C in summer and minimum temperatures of 6 0 C in winter. The annual rainfall ranges 1,050-1,100 mm. It has a total forest area of 2,75,924.38 ha, with 1,91,607.32 ha of reserved forests and 84,317.06 ha of protected forests (ISFR 2019).

Sampling sites
Three different habitats were selected: forest (Malthone, Dhana 1 and Shahgarh range), agricultural (Patheriya Jat, Rajaua, Deori) and agroforestry (Rehli, Dhana 2, and Rahatgarh). The surveys were conducted during October 2017 to October 2021. A total of 42 quadrates with 20m x 20m dimensions were established in selected sites of the district.

Collection
Spider specimens were collected by active visual searching, vegetation beating, net sweeping, and hand picking following Sørensen et al. (2002). All surveys were conducted from 8000 h to 1200 h, with an opportunistic night time survey conducted as well. Spiders were collected and photographed with a DSLR camera (Canon

RESULTS
The Sagar district, Madhya Pradesh is home to a variety of spider species. During the entire study period 1,505 specimens were collected from the study area belonging to 74 species under 22 families (Table 1; Images 1-69). The number of families, genera, species, number of individuals and percentage of number of individuals in particular families are enlisted in Table  2. Araneidae was the dominant family with 19 species from nine genera, followed by Salticidae with 14 species from 13 genera. The seven different guild types include orb-web builders, sheet web weavers, space builders, stalkers, foliage hunters, ambushers, and ground runners ( Figure 2). Orb weavers (14 species) made up the most common feeding guild, accounting for 630 spider specimens (42%) of the overall population, followed by stalkers 373 spiders, 19 species (25%), space builders, 197 spiders, four species (13%), sheet web weavers, 132 spiders, one species (9%), foliage runners 95 spiders, six species (6%), ambushers 48 spiders, eight species (3%) and ground runners with 30 spiders, six species (2%) (Figure 2). During the survey, more spiders were seen in forest and agroforestry habitats than in agriculture habitat. Abundance of spiders was high in 2020 and 2021 ( Figure 3).

DISCUSSION
In the present investigations 22 families have been reported from different sites of Sagar district. Gajbe (2007), Patil et al. (2013), and Patil et al. (2016) in their studies reported 24, 7, and 12 families respectively from Jabalpur and nearby places. Gajbe & Gajbe (2004) reported that most spiders which live on the ground or in plants have some form of camouflage. Some of the noteworthy examples of mimics seen in the present study are the ant-mimicking spiders of genus Myrmaplata, spiders of genus Cyclosa resembling trash, Tetragnatha species resembling twigs or reed tips, while Hersilia camouflage themselves perfectly with the surroundings. Analyzing the spider diversity patterns in Sagar district environment provides valuable information which can be used to validate the ecosystem's balance. The present study was undertaken with the objective to document the spider fauna of Sagar district and prepare the first   www.threatenedtaxa.org The Journal of Threatened Taxa (JoTT) is dedicated to building evidence for conservation globally by publishing peer-reviewed articles online every month at a reasonably rapid rate at www.threatenedtaxa.org. All articles published in JoTT are registered under Creative Commons Attribution 4.0 International License unless otherwise mentioned. JoTT allows allows unrestricted use, reproduction, and distribution of articles in any medium by providing adequate credit to the author(s) and the source of publication.