Songklanakarin J. Sci. Technol. 42 (4), 873-878, Jul. - Aug. 2020 Original Article Mature gonadal histology and gametogenesis of the tortoise beetle Aspidimorpha sanctaecrucis (Fabricius, 1792) (Coleoptera: Cassidinae: Chrysomelidae): Histological observation Piyakorn Boonyoung 1 , Sinlapachai Senarat 2* , Jes Kettratad 3 , Wannee Jiraungkoorskul 4 , Narit Thaochan 5 , Kong-Wah Sing 6 , Theerakamol Pengsakul 7 , and Pisit Poolprasert 8 1 Department of Anatomy, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, 90110 Thailand 2 Department of Marine Science and Environment, Faculty of Science and Fisheries Technology, Rajamangala University of Technology Srivijaya, Trang Campus, Sikao, Trang, 92150 Thailand 3 Department of Marine Science, Faculty of Science, Chulalongkorn University, Pathum Wan, Bangkok, 10330 Thailand 4 Department of Pathobiology, Faculty of Science, Mahidol University, Ratchathewi, Bangkok, 10400 Thailand 5 Department of Pest Management, Faculty of Natural Resources, Prince of Songkla University, Hat Yai, Songkhla, 90112 Thailand 6 State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, 650223 China 7 Faculty of Medical Technology, Prince of Songkla University, Hat Yai, Songkhla, 90110 Thailand 8 Program of Biology, Faculty of Science and Technology, Pibulsongkram Rajabhat University, Mueang, Phitsanulok, 65000 Thailand Received: 1 December 2017; Revised: 5 April 2019; Accepted: 16 May 2019 Abstract The gonadal structure of insects has been well reported but there is a lack of such information from tortoise beetles that are an economically important insect. In this study, the gonadal structure and differentiating stage of gametogenesis of tortoise beetles Aspidomorpha sanctaecrucis are examined using the histological technique. At the level of light microscopy, our results revealed that the A. sanctaecrucis male reproductive system has a pair of testicular structures that consist of six seminiferous tubules. All zones contained various stages of spermatogenesis and could be divided into five stages depending on the shape and histological organization, particularly chromatin organization, which was divided into spermatogonia, primary spermatocytes with 8 sub-steps (leptotene, zygotene, pachytene, diplotene, diakinesis, metaphase, anaphase, and telophase), secondary spermatocytes, spermatids (two sub-steps), and spermatozoa. A pair of ovaries was observed in the female A. sanctaecrucis. Each ovary is considered to be a meroistic ovariole that exists with nurse cells. The differentiating oogenic stages including previtellogenic and vitellogenic stages were observed. Our study provides baseline data that will be useful for future work involved in the ultrastructure and physiology of the reproductive tissue in tortoise beetles, especially the differential characterizations of the seminiferous tubule and ovarian type in beetles. Keywords: germ cell, tortoise beetle, microanatomy, reproductive system *Corresponding author Email address: senarat.s@hotmail.com