DNA Barcoding Of Spider Family Lycosidae And Genus Pireneitega (Agelenidae)

Spider is the common name for animals that belongs to the Arthropoda,Arachnida and Araneae,which is one of the most ancient creatures on Earth.It is widely distributed in all continents except the Antarctica and is one of the major invertebrate animals among land ecosystems.Morphologically,spiders can be identified only for mature individuals because the genitalia are the most important factor for traditional taxonomy.Misidentifications and synonyms can be made by a few interspecies'differences.Among all spider species,the wolf spiders(Lycosidae)have an extreme chaotic taxonomy system because of their familiar appearance,and few differences among species.The genus Pireneitega(Agelenidae)also faces the same circumstance.Hence,a better common method to assist taxonomy research is required.DNA barcoding is a new tool for species identification,which can avoid some of the limitations of morphological identification.This molecular technology has provided a new direction for taxonomy and become an intriguing hotspot in the taxonomy researches since it proposed.DNA barcoding that is based on mitochondria cytochrome c oxidase I(COI)has been widly proved among the animal kingdom as an efficient identification tool for species identification and the discovery of cryptic species or new species.Besides,to establish a DNA barcoding database for certain species can provide convenience for nonprofessional person to identify species,and can also help to protect species diversity and gene diversity.This study focuses on the effectiveness of COI DNA barcoding in the species identification from Lycosidae and genus Pireneitega.The main work and results of present study are as the following:1.In the present study,210 individuals of the 66 spider species of Lycosidae were barcoded using partial DNA sequence of the COI gene.In total,we have analysised 974 sequences of 152 species in 13 genus with COI sequences of Lycosidae downloaded from BOLD and Genbank.85.5%of the spider can be identified through DNA barcoding based on analysis of genetic distance based on K2P model and NJ tree method.2.The results showed that in the genus Piratula and Pardosa appeared larger intraspecific genetic distances than other genus have appeared.Our results suggested that the taxonomy studies of genus Piratula may aquire further investment.As for the genus three Spinarctosa species that can not formed monophyly in the NJ tree while the interspecific distances(0.15-1.57%)of which are lower than other lycosids(2.00%).Our results suggested that the taxonomy studies of this genus may aquire further investment.The result might be explained by the hypothsis that this group is suffering a quick speciation,which lead DNA barcoding's inable to distinguish some sibling species.A combination of multiple genes may solve the problem.The other species within Lycosidae can be identified through genetic distance and NJ tree,which were congruent with the morphological identification.This study confirms the efficiency of COI DNA barcoding in species identification in the family Lycosidae.3.DNA barcoding is also applied in Agelenid genus Pireneitega,which is hard to be morphologically distinguished among different Pireneitega species.The COI genes from 35 specimens of 7 Pireneitega species and 4 specimens of 2 Platocoelotes species(outgroup)were sequenced.The pairwise intra-and interspecific distances were assessed.The results showed that interspecific distances ranged from 11.40%to 16.10%in this genus,while intraspecific distances ranged from 0 to 5.70%.The barcoding gap was obvious within interspecific and intraspecific distance.All the 7 species formed distinct clusters in the NJ trees.Three morphologically confused species,P.spinivulva,P.luctuosa and P.xinping were also well supported,and shows that they are separated species.