Molecular Phylogeny of Pacific Archigregarines (Apicomplexa), Including Descriptions of Veloxidium leptosynaptae n. gen., n. sp., from the Sea Cucumber Leptosynapta clarki (Echinodermata), and Two New Species of Selenidium
Molecular Phylogeny of Pacific Archigregarines (Apicomplexa), Including Descriptions of Veloxidium leptosynaptae n. gen., n. sp., from the Sea Cucumber Leptosynapta clarki (Echinodermata), and Two New Species of Selenidium
复制标题
太平洋Archigregarines (Apicomplexa) 的分子系统发育，包括Veloxyium leptosynaptae n. 的描述。
DOI：
10.1111/j.1550-7408.2012.00616.x
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发表时间：
2012
影响因子：
2.2
通讯作者：
B. Leander
中科院分区：
文献类型：
--
作者：
K. Wakeman;B. Leander
尽管人们对海洋无脊椎动物的肠道寄生虫知之甚少，但它们对了解顶复合体进化的早期阶段至关重要。先前的研究表明，archigregarines是一种副进化的茎群，其他的gregarines谱系，可能还有所有其他的顶复合体群，都是从它进化而来的。然而，证实这一推断是困难的，因为来自石竹精和其他石竹精的分子系统发育数据非常有限。为了帮助填补我们对archigregarine多样性和系统发育知识的空白，我们开始使用高分辨率光学和扫描电子显微镜以及来自单细胞（SC） PCR技术的小亚基（SSU） rDNA序列分析来发现和表征archigregarine的新谱系。本文描述了硒属（Selenidium idanthyrsae n. sp.）和硒属（Selenidium boccardiellae n. sp.）两个新种，并证实了先前报道的硒属（s.c.m esnili）的表面形态和分子系统发育位置。我们还描述了一个新属，veloxdium leptosynaptae n. gen., n. sp.，它与环境序列分支，共同形成了海洋eugregarines（即lecudinids和urosporids）的不同分支的最近的姐妹谱系。这一分子系统发育结果与顶复合体中石蒜氨酸深度副生的假设相一致，表明趋同进化在形成石蒜氨酸滋养体多样性方面发挥了重要作用。
Although archigregarines are poorly understood intestinal parasites of marine invertebrates, they are critical for understanding the earliest stages in the evolution of the Apicomplexa. Previous studies suggest that archigregarines are a paraphyletic stem group from which other lineages of gregarines, and possibly all other groups of apicomplexans, evolved. However, substantiating this inference is difficult because molecular phylogenetic data from archigregarines, in particular, and other gregarines, in general, are severely limited. In an attempt to help fill gaps in our knowledge of archigregarine diversity and phylogeny, we set out to discover and characterize novel lineages of archigregarines with high‐resolution light and scanning electron microscopy and analyses of small subunit (SSU) rDNA sequences derived from single‐cell (SC) PCR techniques. Here, we describe two novel species of Selenidium, namely Selenidium idanthyrsae n. sp. and S. boccardiellae n. sp., and demonstrate the surface morphology and molecular phylogenetic position of the previously reported species S. cf. mesnili. We also describe a novel genus of archigregarine, Veloxidium leptosynaptae n. gen., n. sp., which branches with an environmental sequence and, together, forms the nearest sister lineage to a diverse clade of marine eugregarines (i.e. lecudinids and urosporids). This molecular phylogenetic result is consistent with the hypothesis that archigregarines are deeply paraphyletic within apicomplexans, and suggests that convergent evolution played an important role in shaping the diversity of eugregarine trophozoites.