| The research of insect taxonomy and phylogeny are all required to have a strong research basis of insect morphology. The wing outlines of owlflies have a very rich diversity. However, the research about morphological characteristics of them has been very weak for a long time. Lack of methods for accurately describing and analyzing is the main reason for this. To solve this problem, the study tries to describe and analyze the characteristics using geometric morphological approaches, and furthermore to summarize the distribution pattern and the variation law of wing outlines of owlflies, and even to investigate the evolutionary trend of them.In this study, the front and hind wing outlines of69genera222species of owlflies were quantitatively described by elliptic Fourier analysis. Based on the characteristics data of wing outlines, the wing contour shapes were reconstructed. The reconstructed shape contours provide a way to visualize the shape variation described by the individual principal components. From the overlapped reconstruction figures on the first three principle components, the main variation positions and changing trends of wing outlines have been found. PCA scatter plots reveal the range and the discrete direction of the variation in some parts of the wing contour, and reveal that the wing contour shapes of the majority of the samples bear similarity to the contour shape of the average wing. According to the cluster results on the wing contour features using unweighted pair-group method with arithmatic means analysis (UPGMA), the front wing outlines were reduced to10types and the hind wing outlines were reduced to11types on0.04Euclidean distances classification criterion. On the basis of these results, the wing contours of222species were reduced to48wing-outline combinations types. The five types, Ⅱ-Ⅶ, Ⅱ-Ⅷ, Ⅱ-Ⅲ, Ⅱ-Ⅶ, Ⅷ-Ⅰ and Ⅴ-Ⅷ, are the most common wing-outline combination of all.After that, the distribution pattern of the wing-outline combinations in the six zoogeographical regions was studied. We found that the order of wing outline diversity in the six zoogeographical regions is highly consistent with the order of species diversity, which indicated that the variation of wing contours has a significant impact on the differentiation of species. The analysis results about distribution pattern of wing-outline combinations in typical climate proved that temperate zone is a region where the highest percentage of primitive species of owlfly retained. Finally, based on the principles of cladistic biogeography, the evolutionary relationships among the distribution regions of wing-outline combination were analyzed by parsimony analysisof endemism, a method of historical biogeography. All of the above research results support the following inference:1) the primitive owlfly species should appear before the continental plate cracking;2) Ⅱ-Ⅲ is the most primitive wing-outline combination so far;3) the primitive proportion of the wing-outline combinations of Austrilian and Palaearctic are larger than those of the other regions, and the differentiation of Neotropical species is the fastest of the six zoogeographical regions;4) the evolution of wing-outline combination of owlflies is adaptive radiation from the primitive to other different ways. Besides, by quantitative analysis of the the wing outlines of145samples from eight species of owlflies, the wing outline data are determined as a valuable classification feature and can be used effectively in the classification of some genera of Ascalaphidae.It is the first time to use the geometric morphometric approaches to quantitatively describe and analyze the wing outline of owlflies, and establish the systems of extracting and detecting wing-shaped features accurately, the results of which provide a significant basis for the taxonomy and phylogeny research of owlflies and lay a good researching foundation for automatical identification insect species in computer. |
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