| The family Enidae is an important landsnail group (Gastropoda, Euthyneura) distributed in Eurasia, North Africa and North Australia. In China, the group, mainly distributed in the western mountainous regions, is consist of near two hundred known species and subspecies and in diversity the group is second only to Bradybaenidae.In China, different soil types, vegetation, landscapes and climate conditions provide an arena for the landsnails to display their adaptive changes and take their particular evolutionary diversifications generation by generation. As the result of long-term adaptive radiation and speciation, a quite malacodiversity has been made in Western China, where today drastical changes in environments are frequently happened. This situation raises the question of both conservation and before the action of conservation, the necessary knowledge should be prepared because as we know globally these fragile organisms are suffering both the direct annihilation and the most dangerous threatening, as revealed by the IUCN Redlist2012:the extinction for mollusc5.24%, endangered and critically endangered proportion16.64%. Especially, the landsnails are much more endangered nowadays than those from marine and freshwater. I studied the material collected recently from Gansu, Sichuan, the neighbouring regions on the slope of Qing-Zang Plateau, and the south slope of the Himalayas in Nepal, where a few species were reported to be most morphologically related to a few Chinese species. The total DNAs were obtained from more than200specimens from46species of eight genera. More normally preserved specimens were morphologically studied and ten anatomical characters were particularly examined. The mitochondrial COI and16S rRNA genes, and ribosomal5.8S, ITS-2and partial28S genes were sequenced and employed in the phylogenetic inferences. To make more reliable phylogeny, both the maximum likelihood method and Bayesian inference method were used and the phylogenies suggested by the ML trees and the BI trees were carefully considered and compared before any temporary conclusion was made.Phylogenies based on mitochondrial16S rDNA and COI but that based on nuclear LUS13sequences suggested that China’s enids were included in a monophyletic group. All gene trees indicated that Nepalese Pupinidius was monophyletic, and they were the sister group of "Holcauchen" sp.3. But Pupinidius siniayevi resembled Chinese "Pupinidius" sp.1and "Pupinidius" sp.2in conchological and genitalian features.The branch composed of Clausiliopsis schalfejewi, C. hendan, C. clathratus, C. phaeorhaphe, C. elamellatus,"C." sp.3and the species of the genus Pupopsis was suggested to be monophyly as inferred by16S and ITS-2datasets, while both genera were not monophyletic. The type species of the genus Pupinidius, P. pupinidius was always sibling to Petraeomastus moellendorffi but poorly related to the other Pupinidius congeners. In the BI trees based on COI and ITS-2genes, the branch of Pupinidius siniayevi and another two branches consisting of "P." sp.1,"P." sp.2,"P.’ sp.3,"P." sp.4and P. nanpingensis were very systematically related.After examining the distribution of the ten selected characters mapped on the cladogram resulted from16S rDNA sequence anlysis, using Nonparametric Runs test, six characters, namely peristome continuous status, palatal tooth status, epiphallus twisted status, bursa copulatrix duct twist status, penial caecum status and relative length of vagina, were suggested to be poorly valuable in describing the evolution of monophylies inferred here. Only four characters, namely the parietal tooth status, columellar tooth status, epiphallic caecum status and divertical of bursa copulatrix duct terminally expanded status, contributed much in defining monophylies and indicated their values in the definition of the supraspecific taxa of Chinese enids. |
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