Grupo de Investigación GEBIOME, Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Caldas, Calle 65 No. 26-10 Apartado Aéreo 275 Manizales, Caldas, Colombia.
Ciencias - Biología, Facultad de Ciencias Exactas y Naturales, Universidad de Caldas, Calle 65 No. 26-10 A.A. 275 Manizales, Caldas, Colombia.
Parasitol Res. 2020 May;119(5):1573-1582. doi: 10.1007/s00436-020-06662-y. Epub 2020 Apr 7.
The systematics of several ticks species (Acari: Ixodidae) remains controversial. Many species, including those of the Amblyomma cajennense complex and Rhipicephalus sanguineus s.l., are given special attention since they are cryptic species complexes and are also important in human and veterinary medicine. The A. cajennense complex was recently reorganized into six valid species, among which Amblyomma patinoi and Amblyomma mixtum have been confirmed in Colombia. On the other hand, the taxonomic status of R. sanguineus s.l. is controversial since it is a cosmopolitan cryptic species complex with a high reproductive capacity and a broad range of hosts (including man). To address this challenge, the germ cells of male ticks display a diverse morphology that offers novel opportunities for taxonomy. This study describes the events of spermatogenesis in A. mixtum and R. sanguineus s.l. individuals collected during active feeding on domestic hosts in the department of Caldas, Colombia. The individuals were identified using dichotomous keys and through PCR amplification of a fragment of the mitochondrial 16S ribosomal DNA gene. The male reproductive systems of A. mixtum and R. sanguineus s.l. were fixed in 2.5% glutaraldehyde for 48 h and dehydrated in increasing dilutions of ethanol. The samples were then embedded and mounted in historesin to obtain sections of 3 μm that were stained with hematoxylin-eosin (HE), photographed, and visualized through optical microscopy. The results show that the morphology of mature germ cells displays excellent diagnostic traits that can be used for tick taxonomy.
几种蜱（蜱螨目：硬蜱科）的系统发育仍然存在争议。许多物种，包括 Amblyomma cajennense 复合体和 Rhipicephalus sanguineus s.l. 物种，因其是隐种复合体且在人类和兽医医学中很重要而受到特别关注。最近，A. cajennense 复合体被重新组织成六个有效种，其中 Amblyomma patinoi 和 Amblyomma mixtum 已在哥伦比亚得到确认。另一方面，R. sanguineus s.l. 的分类地位存在争议，因为它是一个具有高繁殖能力和广泛宿主（包括人类）的世界性隐种复合体。为了解决这一挑战，雄性蜱的生殖细胞表现出多样化的形态，为分类学提供了新的机会。本研究描述了在哥伦比亚卡尔达斯省活体取食家养宿主的 Amblyomma mixtum 和 R. sanguineus s.l. 个体中发生的精子发生事件。个体使用二歧分类钥匙和通过线粒体 16S 核糖体 DNA 基因片段的 PCR 扩增进行鉴定。A. mixtum 和 R. sanguineus s.l. 的雄性生殖系统用 2.5%戊二醛固定 48 小时，然后用乙醇逐级稀释进行脱水。然后将样品包埋并安装在组织树脂中，以获得 3μm 的切片，用苏木精-伊红（HE）染色，拍照，并通过光学显微镜观察。结果表明，成熟生殖细胞的形态显示出良好的诊断特征，可用于蜱的分类学。
