Identification of Indian Spiders through DNA barcoding: Cryptic species and species complex

Abstract

Spiders are mega diverse arthropods and play an important role in the ecosystem. Identification of this group is challenging due to their cryptic behavior, sexual dimorphism, and unavailability of taxonomic keys for juveniles. To overcome these obstacles, DNA barcoding plays a pivotal role in spider identification throughout the globe. This study is the first large scale attempt on DNA barcoding of spiders from India with 101 morphospecies of 72 genera under 21 families, including five endemic species and holotypes of three species. A total of 489 barcodes was generated and analyzed, among them 85 novel barcodes of 22 morphospecies were contributed to the global database. The estimated delimitation threshold of the Indian spiders was 2.6% to 3.7% K2P corrected pairwise distance. The multiple species delimitation methods (BIN, ABGD, GMYC and PTP) revealed a total of 107 molecular operational taxonomic units (MOTUs) for 101 morphospecies. We detected more than one MOTU in 11 morphospecies with discrepancies in genetic distances and tree topologies. Cryptic diversity was detected in Pardosa pusiola, Cyclosa spirifera, and Heteropoda venatoria. The intraspecies distances which were as large as our proposed delimitation threshold were observed in Pardosa sumatrana, Thiania bhamoensis, and Cheiracanthium triviale. Further, shallow genetic distances were detected in Cyrtophora cicatrosa, Hersilia savignyi, Argiope versicolor, Phintella vittata, and Oxyopes birmanicus. Two morphologically distinguished species (Plexippus paykulli and Plexippus petersi) showed intra-individual variation within their DNA barcode data. Additionally, we reinstate the original combination for Linyphia sikkimensis based on both morphology and DNA barcoding. These data show that DNA barcoding is a valuable tool for specimen identification and species discovery of Indian spiders.

DNA barcoding and molecular phylogeny of Dumasia (Fabaceae: Phaseoleae) reveals a cryptic lineage

“…DNA barcoding is not only for species identification, but also for evolutionary, ecological, and conservation research ( Hebert et al., 2003 ; Valentini et al., 2009 ; Li et al., 2011a ; Liu et al., 2018 ; Leese et al., 2018 ). In addition, the use of DNA barcodes has also led to the discovery of many new and/or cryptic species (e. g., Hebert et al., 2004 ; Bączkiewicz et al., 2017 ; Tyagi et al., 2019 ). Accordingly, DNA barcoding has become an effective tool for uncovering hidden diversity and has enhanced our understanding of biodiversity ( Gregory, 2005 ; Kress et al., 2005 ; Li et al., 2011b ).…”

Mitochondrial DNA discriminates distinct population of two deadly snakes (Reptilia: Elapidae) in Northeast India

“…The DNA-based species identification is largely used as an effective tool for systematics research, biodiversity assessment, and forensic sciences (Hebert et al 2003;Dubey et al 2011;Tyagi et al 2019). These molecular techniques are tremendously used to identify the snakes from widespread geographical regions (Nagy et al 2012;Chambers and Hebert 2016).…”

DNA barcoding of selected short-horned grasshoppers (Orthoptera: Acrididae) from Indian Himalayan region

“…Molecular tools such as DNA barcoding have been largely supplemented with systematics studies for addressing species identification and other biological questions (Hebert et al 2003;Tyagi et al 2017). This advanced technology has also evidenced to discriminate different taxonomic groups including orthopterans (Huang et al 2013;Singha et al 2019;Tyagi et al 2019). As of now, several studies have been conducted to elucidate the accurate species identification, estimation of genetic divergence, phylogenetic relationship, detection of cryptic diversity, and species complexes of this insect group (Wang et al 2008;Chapco and Contreras 2011;Song et al 2018).…”

“… 2019 ; Tyagi et al. 2019 ). As of now, several studies have been conducted to elucidate the accurate species identification, estimation of genetic divergence, phylogenetic relationship, detection of cryptic diversity, and species complexes of this insect group (Wang et al.…”