Japanese Camponotus (Camponotus Japonicu) Polymorphism Of Worker Ants

Camponotus japonicus Mayr belongs to Hymenoptera, Formicidae, Formicnae and Camponotus Mayr. Camponotus japonicas Mayr is widely scattered over the east part of the Asian, including Chinese Mainland, Southeast Asia, the Korean Peninsula, Japan and the Far East Region of Russia. It is classified into the multi-divisional social insect. The colony of ant usually comprises several classes, including queen, soldier, worker and male. In classic taxonomy, workers divide into two classes, bigger and middle/smaller, according to head width. However, whether middle/smaller class of worker would regard as two classes have been disputed. In addition, nothing is know about morphological variation of workers in each class. In this study, it applies geometric morphometrics using a large number specimens to discussion on above two problems.Polymorphism research on1554Camponotus japonicas specimens from18colonies of18different regions in China is performed. The regression curve evaluation by traditional way what it measure the maximum width between the two ommateums periphery and the maximum width alitrunk; establishment of regression curve equation by utilizing the centroid size of head and alitrunk; Establishment of regression curve equation by utilizing the centroid size of head and alitrunk, the regression curve equation Should comply with the function y=bxa. Selecting20landmarks on the head of each specimen using the geometric morphometric method, setting the line between the first and the20th landmarks as the baseline, selecting10more landmarks on the alitrunk, and setting the line between the first and6th landmarks as the baseline, taking advantage of Canonical variate analysis (CVA) to analyze the multivariate data structure and compare the polymorphism in respective ant colony. The experiment results are as follows:1. It is deduced through the classic approach that the a-value of insect colonies originated from Mount Taibai, Xi’an and Shiyan are greater than one, the rest of the colonies bear values less than one. It is also can be concluded that monophasic allometry has occurred to the maximum width of both the outer edge and the alitrunk as monomorphism of Camponotus japonicas. 2. It is deduced through establishment of regression curve equation by utilizing the centroid size of head and alitrunk, the a-values derived from Mount Taibai, Jinan, Xuzhou, Luoyang, Beijing, Jinhua, Shiyan, Nanning, Kunming, Nanyang, Shen Nongjia, Tianshui and Liuba are all greater than one, the rest of the insect colonies share a-values less than one. The fact that both a-values from Mount Taibai and Jinan share proximity to one announces the impossibility of divergence. It can infer that monophasic allometry has occurred to the maximum width of both the outer edge and the alitrunk as monomorphism of Camponotus japonicas head and alitrunk.3. The scatter diagram and regression curve equation drawn from the combination of classic approach and measurement of alitrunk centroid size are adequate proofs to certify that there is a complete dimorphism in small and medium sized workers and large sized workers, thus it is obvious that the large sized workers belong to the soldier ant category. Non-distinct differences endowed in small and medium sized workers define them as the worker rank of Camponotus japonicas. Still, there is certain diversity in the allometry regression curve equation in various insect colonies. The allometry regression curve equation deduced from different measurements amid the same colony also has certain diversity.4. The head form of a singular insect colony falls into two distinctive categories by utilization of the geometric morphometric method. There is apparent change in occipital horn, ommateum, frontal area, buccal, clypeus and the mid-ridge of clypeus. Different insect colonies have different varieties, but judging from characters revealed in x axis and y axis, allometry still remains.5. There is no distinctive morphological difference in the singular alityunk, and its development belongs to singlet development. No obvious difference is in inter-colony development.