Acta Entomologica Sinica ›› 2019, Vol. 62 ›› Issue (3): 312-322.doi: 10.16380/j.kcxb.2019.03.005

• RESEARCH PAPERS • Previous Articles     Next Articles

Observation of antennal sensilla of the malaria vector Anopheles sinensis (Diptera: Culicidae) under scanning electron microscope

ZHANG Jing, ZHANG Jing-Jing, SHI Zong-Pan, YAN Zhen-Tian, CHEN Bin, HE Zheng-Bo*   

  1.  (Chongqing Key Laboratory of Vector Insects, Institute of Entomology and Molecular Biology, Chongqing Normal University, Chongqing 400047, China)
  • Online:2019-03-20 Published:2019-03-14

Abstract: 【Aim】 To determine the type, morphology and distribution of antennal sensilla of female adults and larvae of Anopheles sinensis. 【Methods】 The morphological structure of the antennae of female adults and larvae of An. sinensis were observed under optical microscope, and the types, morphology and distribution of sensilla were observed under scanning electron microscope. 【Results】 The female antennae of An. sinensis adults are comprised of basal scape, pedicel, and a long flagellum with 13 flagellomeres. Four types of sensilla, including sensilla trichodea (sharp- and blunt-tipped), sensilla chaetica (large and small), sensilla basiconica or grooved pegs (types I and II) and sensilla coeloconica (large and small), were found on the female antennae of adults. Averagely the flagellum is covered with 1 135.67±86.75 sensilla. Among them, sensilla trichodea are the most numerous sensilla type found on the flagellum (662.00±6.22), followed by sensilla chaetica (294.67±33.35), sensilla basiconica (146.00±42.39) and sensilla coeloconica (36.50±5.90). Sensilla trichodea, sensilla chaetica and sensilla basiconica are distributed on each flagellomere, while the large sensilla coeloconica were not found on the 9th-11th flagellomeres, and the small sensilla coeloconica were only found on the distal tip of flagellomere 13. There is only one tubular flagellomere on larval antennae with a terminal sensory cone. Many pegs similar to the sensilla basiconica of female adults were found on the tubular flagellum, which were tentatively named as sensilla basiconica-like. Their numbers and sizes dramatically increase with the larval instar, and the grooves along the surfaces gradually become obvious, but their functions need to be further determined through ultrastructural and electrophysiological analysis. 【Conclusion】 In this study the morphological characteristics, type, number and distribution of antennal sensilla of An. sinensis larvae and female adults were observed and analyzed. The results provide a basis for further investigating the physiological functions of the sensilla of An. sinensis.

Key words: Anopheles sinensis; antenna, morphology, sensilla, ultrastructure, scanning electron microscopy