| Genus Oberea Dejean,1835belonging to subfamily Lamminae, family Cerambycidae, order Coleoptera consists of2subgenera, more than300species. Oberea is widely distributed in most zoogeographical realms. Generally, some Oberea species are economically important to agriculture and forestry. The present dissertation introduces the brief research history, general morphology of Oberea. All the species from China are described in details. The taxonomic characters are compared. The phylogenetic study on Oberea is made based on the morphological characters. The sequences of DNA barcode based on COI are extracted. The zoogeography of Oberea is analyzed. The principal results of the present dissertation are listed as follows:1. TaxonomyIn the taxonomic section,77species (subspecies) of Oberea are recorded and described in details base on more than700specimens, including more than60type specimens. A new species, six new country records, six status resurrected, six new synonym and three new combinations are recorded. The adult habitus of73species and male genitalia of51species are provided.One new species:Oberea pseudoformosana Li, Cuccodoro&Chen,2014(published)Three new recorded species to China:O. subabdominalis Breuning,1962O. angustata Pic1923O.pupillata (Gyllenhal,1817).Six new synonyms:O. taiwana Matsushita,1933=O. taihokuensis Breuning,1962syn.nov.O. angustata Pic,1923=O. ohbayashi Kurihara2009. syn. novO. clara Pascoe,1866=O.fuscipennis ssp. perakensis Breuning,1962syn. novO. hebescens Bates,1873=O. diversimembris Pic,1923syn. novO. diversipes Pic,1919=O. fuscipennis ssp. fairmairei Breuning,1962syn. novO. walkeri Gahan,1894=0. bicoloritarsis v. subparallela Pic,1928, syn. nov. Three new combinations:Obereopsis subsericea (Breuning,1960) comb. nov.=Oberea subsericea Breuning,1960Obereopsis binotaticollis chinensis comb. nov.=Oberea griseopennis chinensis Breuning,1982Obereopsis binotaticollis ichangensis (Breuning,1969) comb. nov.=Oberea griseopennis ichangensis Breuning,1969Seven status resurrected:O. flavescens Breuning,1947stat. rev.,O. sylvia Pascoe,1858stat. rev.O. binhana Pic,1923stat. rev.O. diversipes Pic,1919stat. rev.O. toi Gressitt,1939stat. rev.O. infratestacea Pic,1936stat.rev.O. thibetana Pic,1916stat. rev..Seventy-nine infrasubspecific names are revised.2. Comparative morphologyThe present comparative morphology research is based on40morphological characters of which27taxonomic characters can be used.There are6taxonomic characters of head:color of head, shape of frons, ratio of lower lobe of eyes and genea, antennal length, third/fourth antennal segment, groove on the dorsal surface of scape,.There are11taxonomic characters of thorax and abdomen:ratio between length and width of prothorax, elytral apex rounded or truncated, outer elytral angles with or without spine, punctures on the elytral disc, silky pubescence on the elytra, length of hind femora, ratio of hind tibae and tarsis, silky pubescence on the abdominal segments, the finger-like protuding of the first visible abdominal segment of males and color of last visible abdominal segment.There are10taxonomic characters of male genitalia:shape of tergite VIII, shape of lateral lobes, number, symmetry of sclerity in apical endophallus, ratio between long pairs and short pairs, and so on.Based on the results of comparative morphology, some species have been redescribed and revised, and the keys to subgenera and species are established.3. Phylogenetic analysisThe phylogenetic relationship among the55species of Oberea is re-constructed based on the26morphological characters.The NJ tree shows that Oberea is a paraphyly because outgroup Linda are gathered within Oberea. The relationship of Linda and Oberea need further study.Species of subgenus Oberea and Amaurostoma are not gathered as independent branch. Thus Amaurostoma should be considered as synonym of Oberea rather than subgenus.According to the relationship between the branch and characters of male genitalia, the classification system of genus Oberea should be reconstructed based on the characters of male genitalia, especially the rods of endopallus. However, the current research involves in the Chinese species only accounting for only1/6of worldwide species. More species, morphological and molecular data are needed for classification system reconstruciton of Oberea.4. DNA barcodeThe658bp sequence of COI extracted from6species,18specimens of Oberea with the COI sequence of5species from GenBank are analyzed. Model Kimura2-parameter (K2P) is used to analyze the genetic distance. And the results shows that the genetic distance among the same species varies from0-2.04%, while that among different species ranged from5.97%-12.74%. It shows that the inter-specific genetic distance is significantly larger than intra-specific genetic distance. Neighbor-joining phylogenetic tree and ML tree are established based on the COI gene sequences. Both NJ tree and ML tree indicate that the same species was gathered in the same branch, with the bootstrap value of100%. The results suggest that DNA barcoding based on mitochondrial COI gene sequences is applicable in the classification and identification of Oberea species.In the taxonomic section, the status of O. diversipes Pic and O. infratestacea Pic which are closely related to O. fuscipennis was resurrected based on the morphology of male genitalia. The inter-specific genetic distance is larger than intra-specific genetic distance. And the same species are gather within the same branch. Therefore, O. diversipes Pic and O. infratestacea Pic are good species. The DNA barcode sequence of three specimens of O. walkeri Gahan, two of which have black spots on the second visible abdominal segment are analyzed. The results indicate that three specimen are the same species and the black spots on the second visible abdominal segment is variation of O. walkeri, which cannot be used for identification of Oberea.5. Zoogeographical distributionAccording to the general data of the geographical distribution and collection records, the distribution patterns of Oberea are summarized both world and China scale.It shows that Chinese Oberea are distributed in Oriental realm and Palearctic realm. And the Oriental realm holds the richest species diversity of Oberea. There are11species are distributed in Palearctic realm, accounting for14.29%. There are46species are distributed in Oriental realm, having the highest proportion of59.74%. There are20species are distributed both in Oriental and Palearctic realm. Species of subgenera Amaurostoma are only distributed in Palearctic realm.In the Chinese zoogeographic region, Center China Region (40species, accounting for51.95%) holds richest species diversity of Oberea, South China Region comes next and Inner Mongolia-Xinjiang Region holds fewest. There are3region types of subgenera Amaurostoma, while22of subgenera Oberea. There are41species distributed in only one region, accounting for56.94%, of which are mainly distributed in Center China region and South China region. The species distributed over two regions are much less.There are41species only distributed in one region, accounting for56.94%. And the species distributed more than2regions are much more less than one region distributed species. There are31endemic species from China, most of which are distributed in South China region and Center China region. |
