The new species Tinocladia sanrikuensis sp. nov. H.Kawai, K.Takeuchi & T.Hanyuda (Ectocarpales s.l., Phaeophyceae) is described from the Pacific coast of the Tohoku region, northern Japan based on morphology and DNA sequences. The species is a spring–summer annual growing on lower intertidal to upper subtidal rocks and cobbles on relatively protected sites. T. sanrikuensis has a slimy, cylindrical, multiaxial erect thallus, slightly hollow when fully developed, branching once to twice, and resembles T. crassa in gross morphology. The erect thalli are composed of a dense medullary layer, long subcortical filaments, and assimilatory filaments of 11–35 cells, up to 425 μm long and curved in the upper portion. Unilocular zoidangia are formed on the basal part of assimilatory filaments. The species is genetically most closely related to T. crassa and has the same basic thallus structures but differs in having thinner and longer assimilatory filaments. DNA sequences of the mitochondrial cox1 and cox3, chloroplast atpB, psaA, psbA and rbcL genes support the distinctness of this species.

中文翻译：

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Tinocladia sanrikuensis sp. 十一月 (Ectocarpales sl ., Phaeophyceae) 来自日本

新种 Tinocladia sanrikuensis sp. 十一月 H.Kawai、K.Takeuchi 和 T.Hanyuda（Ectocarpales sl，Phaeophyceae）根据形态学和 DNA 序列描述于日本北部东北地区的太平洋沿岸。该物种是春夏季一年生生长在相对受保护的地点的较低潮间带至上潮下带岩石和鹅卵石上。T. sanrikuensis 有一个黏糊糊的、圆柱形的、多轴直立的叶状体，完全发育时略微中空，分枝一到两次，在大体形态上类似于 T. crassa。直立的菌体由致密的髓质层、长的皮质下细丝和 11-35 个细胞的同化细丝组成，长达 425 μm，上部弯曲。在同化丝的基部形成单房结节。该物种在遗传上与 T 最密切相关。crassa 并具有相同的基本叶体结构，但不同之处在于具有更细和更长的同化细丝。线粒体 cox1 和 cox3、叶绿体 atpB、psaA、psbA 和 rbcL 基因的 DNA 序列支持该物种的独特性。