Comparative analyses of life-history theory studies are based on the characteristics of the life cycles of different species. For tardigrades, life-history traits are available only from laboratory cultures, most of which have involved parthenogenetic species. The discovery of a new gonochoristic bisexual Mesobiotus species in a moss collected on the island of Elba (Italy) provides us with the opportunity to describe Mesobiotus joenssoni sp. nov. and to collect data on the life-history traits of cultured specimens to increase our knowledge of the life-history strategies present in tardigrades. This new species is differentiated from all other species of the genus by the presence of granules (~1 μm in diameter) on the dorsal cuticle of the last two body segments, two large bulges (gibbosities) on the hindlegs and long, conical egg processes. The species exhibits sexual dimorphism in body length, with females being longer than males of the same age. The mean lifespan of specimens was 86 days, with a maximum of 150 days. The mean age at first oviposition was 19.8 days and the mean egg hatching time 15.4 days. The life-cycle traits correspond to those collected for the only other two macrobiotid species with gonochoric amphimictic reproduction examined so far.

中文翻译：

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来自意大利厄尔巴岛的新淋病两栖性 Mesobiotus joenssoni（Eutardigrada：Macrobiotidae）的生活史特征和描述

生命史理论研究的比较分析是基于不同物种的生命周期特征。对于缓步动物，生活史特征只能从实验室培养物中获得，其中大部分都涉及孤雌生殖物种。在厄尔巴岛（意大利）收集的苔藓中发现了一种新的淋病双性中生菌属物种，为我们提供了描述 Mesobiotus joenssoni sp. 的机会。十一月 并收集有关培养标本的生活史特征的数据，以增加我们对缓步动物生活史策略的了解。这个新物种与该属的所有其他物种的不同之处在于，最后两个身体节段的背侧角质层上存在颗粒（直径约 1 微米），后腿上有两个大凸起（隆起）和长而圆锥形的卵突起. 该物种在体长上表现出性别二态性，雌性比同龄的雄性更长。标本的平均寿命为 86 天，最长为 150 天。首次产卵的平均年龄为 19.8 天，平均卵孵化时间为 15.4 天。生命周期特征对应于迄今为止检查的仅有的其他两种具有淋病两性繁殖的大型生物物种的生命周期特征。