Ciliates within the Mesodinium rubrum/Mesodinium major species complex harbor chloroplasts and other cell organelles from specific cryptophyte species. Mesodinium major was recently described, and new studies indicate that blooms of M. major are just as common as blooms of M. rubrum. Despite this, the physiology of M. major has never been studied and compared to M. rubrum. In this study, growth, food uptake, chlorophyll a and photosynthesis were measured at six different irradiances, when fed the cryptophyte, Teleaulax amphioxeia. The results show that the light compensation point for growth of M. major was significantly higher than for M. rubrum. Inorganic carbon uptake via photosynthesis contributed by far most of total carbon uptake at most irradiances, similar to M. rubrum. Mesodinium major cells contain ~four times as many chloroplast as M. rubrum leading to up to ~four times higher rates of photosynthesis. The responses of M. major to prey starvation and refeeding were also studied. Mesodinium major was well adapted to prey starvation, and 51 d without prey did not lead to mortality. Mesodinium major quickly recovered from prey starvation when refed, due to high ingestion rates of > 150 prey/predator/d.

中文翻译：

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Mesodinium Major 对辐照度、猎物浓度和猎物饥饿的生理反应


红色中甲藻/主要物种复合体内的纤毛虫含有来自特定隐植物物种的叶绿体和其他细胞器。 Mesodinium Major最近被描述，新的研究表明M的开花。 Major和M的花一样常见。红鲁鲁姆。尽管如此， M的生理学。从未研究过专业并与M进行比较。红鲁鲁姆。在这项研究中，当喂食隐生植物Teleaulax amphioxeia时，在六种不同的辐照度下测量了生长、食物摄取、叶绿素a和光合作用。结果表明，光补偿点对M的生长有促进作用。专业明显高于M 。红鲁鲁姆。在大多数辐照度下，通过光合作用吸收的无机碳占总碳吸收的大部分，与M类似。红鲁鲁姆。 Mesodinium主要细胞含有约四倍于M 的叶绿体。 rubrum导致光合作用速率提高约四倍。 M的回应。还研究了猎物饥饿和重新进食的主要影响。 Mesodinium Major能够很好地适应猎物饥饿，51 天没有猎物不会导致死亡。由于 > 150 猎物/捕食者/天的高摄入率，中甲藻在重新进食后很快就能从猎物饥饿中恢复过来。