The external morphology and internal cell fine structure of a new species of Tovelliaceae, Tovellia rubescens n. sp., is described. Phylogenetic analyses based on partial LSU rDNA sequences place the new species in a clade containing Tovellia species that accumulate red pigments and identify T. aveirensis as its closest known relative. Cells of T. rubescens n. sp. were mostly round and had the cingulum located near the middle, with its ends displaced about one cingular width. Small numbers of distinctly flat cells appeared in culture batches; their significance could not be determined. Cells of the new species in culture batches progressively changed from a yellowish‐green, mainly due to chloroplast colour, to a reddish‐brown colour that appeared associated with lipid bodies. The switch to a reddish colour happened earlier in batches grown in medium lacking sources of N or P. Pigment analyses by HPLC‐MS/MS revealed the presence of astaxanthin and astaxanthin‐related metabolites in the new species, but also in T. aveirensis, in which a reddish colour was never observed. The chloroplast arrangement of T. rubescens n. sp. resembled that of T. aveirensis, with lobes radiating from a central pyrenoid complex. The flagellar apparatus and pusular system fell within the general features described from other Tovelliaceae. A row of microtubules interpretable as a microtubular strand of the peduncle was present. Spiny resting cysts with red contents and an ITS sequence identical to that of cultured material of the new species were found in the original locality.

中文翻译：

---

Woloszynskioid Dinoflagellates X 的研究：Tovellia rubescens n 的超微结构、系统发育和颜色变化。sp. （甲藻科）

Tovelliaceae新种Tovellia rubescens n的外部形态和内部细胞精细结构。sp., 进行了描述。基于部分 LSU rDNA 序列的系统发育分析将新物种置于包含 Tovellia 物种的进化枝中，该物种积累红色色素并将 T. aveirensis 确定为其最接近的已知亲属。T. rubescens n. 细胞 sp. 大部分是圆形的，扣带位于靠近中间的位置，其末端移位约一个扣带宽度。培养批次中出现少量明显扁平的细胞；无法确定它们的重要性。培养批次中新物种的细胞逐渐从黄绿色（主要是由于叶绿体颜色）变为与脂质体相关的红棕色。在缺乏 N 或 P 来源的培养基中生长的批次中较早发生了转变为红色。 HPLC-MS/MS 的色素分析表明，新物种以及 T. aveirensis 中存在虾青素和虾青素相关代谢物。其中从未观察到微红色。T. rubescens n 的叶绿体排列。sp. 与 T. aveirensis 相似，具有从中央核蛋白复合体辐射出的裂片。鞭毛器和脓疱系统属于从其他 Tovelliaceae 描述的一般特征。存在一排可解释为花梗微管链的微管。在原地发现了具有红色内容物和与新种培养物相同的ITS序列的多刺休眠包囊。通过 HPLC-MS/MS 进行的色素分析揭示了新物种中存在虾青素和虾青素相关代谢物，但在 T. aveirensis 中也存在，其中从未观察到微红色。T. rubescens n 的叶绿体排列。sp. 与 T. aveirensis 相似，具有从中央核蛋白复合体辐射出的裂片。鞭毛器和脓疱系统属于从其他 Tovelliaceae 描述的一般特征。存在一排可解释为花梗微管链的微管。在原地发现了具有红色内容物和与新种培养物相同的ITS序列的多刺休眠包囊。通过 HPLC-MS/MS 进行的色素分析揭示了新物种中存在虾青素和虾青素相关代谢物，但在 T. aveirensis 中也存在，其中从未观察到微红色。T. rubescens n 的叶绿体排列。sp. 与 T. aveirensis 相似，具有从中央核蛋白复合体辐射出的裂片。鞭毛器和脓疱系统属于其他 Tovelliaceae 描述的一般特征。存在一排可解释为花梗微管链的微管。在原地发现了具有红色内容物和与新种培养物相同的ITS序列的多刺休眠包囊。T. rubescens n 的叶绿体排列。sp. 与 T. aveirensis 相似，具有从中央核蛋白复合体辐射出的裂片。鞭毛器和脓疱系统属于从其他 Tovelliaceae 描述的一般特征。存在一排可解释为花梗微管链的微管。在原地发现了具有红色内容物和与新种培养物相同的ITS序列的多刺休眠包囊。T. rubescens n 的叶绿体排列。sp. 与 T. aveirensis 相似，具有从中央核蛋白复合体辐射出的裂片。鞭毛器和脓疱系统属于从其他 Tovelliaceae 描述的一般特征。存在一排可解释为花梗微管链的微管。在原地发现了具有红色内容物和与新种培养物相同的ITS序列的多刺休眠包囊。