PDF(Pubmed)
Abstract：
Miniaturization is an evolutionary trend observed in many animals. Some arachnid groups, such as spiders and mites, demonstrate a strong tendency toward miniaturization. Some of the most miniaturized spiders belong to the family Anapidae. In this study, using light and confocal microscopy and 3D modelling, we provide the first detailed description of the anatomy of a spider of the genus Rayforstia, which is only 900 µm long. In comparison with larger spiders, Rayforstia has no branching of the midgut in the prosoma and an increased relative brain volume. In contrast to many miniature insects and mites, the spider shows no reduction of whole organ systems, no allometry of the digestive and reproductive systems, and also no reduction of the set of muscles. Thus, miniature spider shows a more conserved anatomy than insects of a similar size. These findings expand our knowledge of miniaturization in terrestrial arthropods.
摘要：
小型化是在许多动物中观察到的进化趋势。一些蜘蛛群，比如蜘蛛和螨虫,表现出强烈的小型化趋势。一些最小型化的蜘蛛属于Anapidae家族。在这项研究中,使用光和共聚焦显微镜和3D建模，我们提供了Rayforstia属蜘蛛的解剖结构的第一个详细描述，它只有900微米长。与较大的蜘蛛相比，Rayforstia在prosoma中没有中肠分支，并且相对脑体积增加。与许多微型昆虫和螨虫相比，蜘蛛显示整个器官系统没有减少，没有消化系统和生殖系统的异速变化,也没有减少肌肉。因此，微型蜘蛛的解剖结构比类似大小的昆虫更保守。这些发现扩展了我们对陆地节肢动物小型化的认识。
