Shin Sang Phil, Shirakashi Sho, Hamano Shogo, Kato Keitaro, Lasso Lissette Trejos, Yokoyama Hiroshi
Fisheries Laboratory, Kinki University, Shirahama, Nishimuro, Wakayama 649-2211, Japan.
Fisheries Laboratory, Kinki University, Shirahama, Nishimuro, Wakayama 649-2211, Japan.
Mol Phylogenet Evol. 2016 May;98:337-45. doi: 10.1016/j.ympev.2016.02.019. Epub 2016 Mar 3.
Kudoa rayformis n. sp. (Myxozoa; Multivalvulida) was observed in the trunk muscle of Pacific sierra Scomberomorus sierra caught off the coast of Tonosi, Panama. The species formed pseudocysts in myofibers and infection was subclinical. The myxospores possessed four polar capsules and spore valves, one of which had a distinct filamentous extension. This unique morphological characteristic of the myxospore validated this as a new species of Kudoa. Genetically, K. rayformis n. sp. is closest to K. inornata, with 98% and 91% similarity in 18S and 28S rDNA, respectively, but its spore shape was clearly distinct. The 18S rDNA and concatenated sequences from K. rayformis were used in molecular phylogenetic analyses of kudoids to examine the congruence of phylogeny with infection site tropism, spore morphology and cyst/pseudocyst formation. The results demonstrated that the phenotypic traits were correlated with the phylogeny of Kudoidae, and that the biological features of K. rayformis originated from the ancient Kudoidae as exhibited by the non-specific infection site tropism and the ability to infect muscle and form pseudocysts.
在巴拿马托诺西海岸捕获的太平洋马鲛（Scomberomorus sierra）的躯干肌肉中发现了雷氏库道虫（Kudoa rayformis）新种（粘孢子虫纲；多瓣虫目）。该物种在肌纤维中形成假囊肿，感染为亚临床感染。粘孢子虫具有四个极囊和孢子瓣，其中一个有明显的丝状延伸。粘孢子虫这种独特的形态特征证实其为库道虫属的一个新物种。在基因方面，雷氏库道虫新种与无饰库道虫最为接近，18S和28S rDNA的相似度分别为98%和91%，但其孢子形状明显不同。雷氏库道虫的18S rDNA和串联序列被用于库道虫类的分子系统发育分析，以检验系统发育与感染部位嗜性、孢子形态以及囊肿/假囊肿形成的一致性。结果表明，表型特征与库道虫科的系统发育相关，雷氏库道虫的生物学特征源于古老的库道虫科，表现为非特异性感染部位嗜性以及感染肌肉并形成假囊肿的能力。
