Thulinius ruffoi is a small freshwater tardigrade that lives in both non-polluted and polluted freshwater environments. As a result of tardigradan body miniaturization, the digestive system is reduced and simplified. It consists of a short fore- and hindgut, and the midgut in the shape of a short tube is lined with a simple epithelium. The midgut epithelium is formed by the digestive cells and two rings of crescent-shaped cells were also detected. The anterior ring is located at the border between the fore- and midgut, while the posterior ring is situated between the mid- and hindgut. The precise ultrastructure of the digestive and crescent-shaped cells was examined using transmission electron microscopy, serial block face scanning electron microscopy and histochemical methods. We analyzed the changes that occurred in the midgut epithelial cells according to oogenesis (the species is parthenogenetic and there were only females in the laboratory culture). We focused on the accumulation of reserve material and the relationship between this and the intensity of autophagy. We concluded that autophagy supplies energy during a natural period of starvation (the simplex stage) and delivers the energy and probably the substances that are required during oogenesis. Apoptosis was not detected in the midgut epithelium of T. ruffoi.

中文翻译：

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Thulinius ruffoi（Tardigrada，Eutardigrada，Parachela）中肠上皮的精细结构与卵子发生和单纯形阶段有关。

Thulinius ruffoi是一种小型淡水龟头，生活在无污染和受污染的淡水环境中。由于tardigradan身体小型化，消化系统得以减少和简化。它由短的前肠和后肠组成，短管形状的中肠衬有简单的上皮。消化细胞形成中肠上皮，还检测到两个月牙形细胞环。前环位于前肠和中肠之间的边界，而后环位于中肠和后肠之间。使用透射电子显微镜，连续块面扫描电子显微镜和组织化学方法检查消化细胞和新月形细胞的精确超微结构。我们根据卵子发生分析了中肠上皮细胞发生的变化（该物种是孤雌生殖，实验室培养中只有雌性）。我们专注于储备材料的积累以及与自噬强度之间的关系。我们得出的结论是，自噬在饥饿的自然时期（单纯形阶段）提供能量，并提供能量以及可能在卵子发生过程中所需的物质。在T. ruffoi的中肠上皮中未检测到凋亡。我们得出的结论是，自噬在饥饿的自然时期（单纯形阶段）提供能量，并提供能量以及可能在卵子发生过程中所需的物质。在T. ruffoi的中肠上皮中未检测到凋亡。我们得出的结论是，自噬在饥饿的自然时期（单纯形阶段）提供能量，并提供能量以及可能在卵子发生过程中所需的物质。在T. ruffoi的中肠上皮中未检测到凋亡。