Morphology Of The Immature Stages Of Algon Sphaericollis Schillhammer,2006 And Taxonomic Study On The Subtribe Algonina(Coleoptera:Staphylinidae:Staphylininae) Of China

The subtribe Algonina Schillhammer & Brunke,2017(Coleoptera: Staphylinidae:Staphylininae: Staphylinini)consists of three genera: Algon Sharp,1874,Barypalpus Cameron,1932 and Rientis Sharp,1874.Presently,88 species of this subtribe are known from the world,all of them strictly distribute in Asia.Twenty nine species are recorded from China,most of them are from southern provinces.The life cycle of Algon sphaericollis Schillhammer,2006 and the immature stages are studied for the first time.Morphological data of egg,mature larva and pupa of taxa of Staphylininae are extracted for maximum parsimony(MP)analysis to verify recent phylogenetic studies based on adult characteristics and molecular information.A taxonomic study based on adult specimens from China is established.The distributional and evolutionary patterns of the subtribe are discussed.The main conclusions are as the followings:1.The populaton of A.sphaericollis from Shanghai overwinters in adult stage,and the larva stage occurs in both spring and autumn.It takes about 39 days for eggs growing to adults,and the adult lifespan is about one year.2.The morphology of egg,larvae of each instars and pupa of A.sphaericollis are described and illustrated.In a phylogenetic test based on immature informations,the50% majority consensus of the MP trees based on 43 features of 35 taxons supports the monophyly of Staphylininae and Staphylinini and the sister relationship of Algonina +Xanthopygina with Phionthina.The different immature phenotype of each group of Staphylininae were derived in adapting to different environments,accompanied by the reversal and convergence,thus the immature morphology shows Mosaic evolution.Selected immature characters of certain taxa are compared,the comparative morphology of immature stages are discussed and keys to the known larvae of subtribes of Staphylininae and larvae of genus of Staphylinini are provided.3.A total of 38 species of Algonina from China are described,including 5 new species and 4 newly recorded species.The new species group,A.tibetanus species group,is established.The morphological comparisons among related species are discussed,and key to species is provided.Based on the the phylogenetic result and the distributions of the species,the historical and geographical patterns of the origin and evolution of Algonina are discussed: the ancestor of Algonina and Xanthopygina once spread across the land bridge in Asia and America during the early Eocene,and separated into two groups due to habitat loss caused by climatic fluctuations since the Tertiary period.