The Species Richness And Niche Divergence Of Panorpidae In The Huoditang Forest Region Of The Qinling Mountains

Scorpionflies(Mecoptera,Panorpidae),as environmental indicator insects,lived in dense vegetations of mountain regions playing important role in the conservation of species diversity of mountain regions.However,their elevational species richness gradient pattern remains unknown.We conducted an ecological monitoring along elevations in the Huoditang Forest Farm of the south slope of the Qinling Mountain for two years.The elevations and emergence dates of 2642 scorpionfly specimens were recorded including 14 species of 6 genera including six species in Cerapanorpa,C.reni(Chou,1981),C.brevicornis(Hua & Li,2007),C.nanwutaina(Chou,1981),C.qinlingensis Gao,Li& Hua,2020,C.sinuata Gao,Ma & Hua,2016,C.dubia;One species in Dicerapanorpa,D.magna(Chou,1981);One species in Neopanorpa,N.longiprocessa Hua & Chou,1997;Four species in Panorpa,P.chengi Chou,1981,P.sexspinosa Cheng,1949,P.curva Carpenter,1938,P.bifasciata;One species in Sinopanorpa,S.tincta(Navás,1931);One species in Furcatopanorpa,F.longihypovalva(Hua & Cai,2009).We counted the elevational richness and emergence number,and explored the relationship between the richness and elevations and community dynamic.Then,cluster analysis was conducted to investigate the formative factors for spatio-temporal niche divergence.Finally,geometric measuring of wings of closely-related species was conducted to test the adaptive evolution of scorpionflies for the environment change.We documented the pattern of elevational richness gradient of scorpionflies in Huoditang Farm in the southern slope of the Qinling Mountains.The result showed that scorpionflies kept hump-shaped pattern of species richness with the richness peak in intermediate elevations.In addition,the linear relationship,between the elevational position and collecting date,was showed.That indicated a movement of scorpionfly community from lower to higher elevations.Niche divergence played different roles in explaining the richness pattern.The allochronic divergence caused by the division of adult emergence induced the temporal niche shift in intermediate elevations.Spatio-temporal niche divergence of closely related species in Cerapanorpa and Panorpa was distinct,especially in three species which were more similar in morphology and had relatively closer relationship in Cerapanorpa.Wing shortening was also detected in these three species.The intermediate elevations,containing the most species richness,was the key region of conservation.In addition,elder species with smaller population and narrow distribution range,such as Cerapanorpa reni and Furcatopanorpa longihypovalva,had higher risk of extinction when they faced the intraspecific competition and rapid change of environment.In conclusion,the elevational richness pattern of scorpionflies was hump-shaped on the south slope of the Qinling Mountains.Allochronic divergence was most occurred in intermediate elevations.Interspecific niche divergence was detected and the spatio-temporal niche divergence of closely related species was more significant.