Køie Marianne, Karlsbakk Egil, Einen Ann-Cathrine Bårdsgjtere, Nylund Are
Marine Biological Laboratory, University of Copenhagen, Helsingør, Denmark.
Folia Parasitol (Praha). 2013 May;60(2):149-54. doi: 10.14411/fp.2013.016.
A myxosporean producing actinospores of the tetractinomyxon type in Hydroides norvegicus Gunnerus (Serpulidae) in Denmark was identified as a member of the family Parvicapsulidae based on small-subunit ribosomal DNA (SSU rDNA) sequences. Myxosporean samples from various Danish and Norwegian marine fishes were examined with primers that detect the novel myxosporean. Sprattus sprattus (Linnaeus) and Clupea harengus Linnaeus (Teleostei, Clupeidae) were found to be infected. The sequences of this parvicapsulid from these hosts were consistently slightly different (0.8% divergence), but both these genotypes were found in H. norvegicus. Disporic trophozoites and minute spores of a novel myxosporean type were observed in the renal tubules of some of the hosts found infected through PCR. The spores appear most similar to those of species of Gadimyxa Køie, Karlsbakk et Nylund, 2007, but are much smaller. The actinospores of the tetractinomyxon type from H. norvegicus have been described previously. In GenBank, the SSU rDNA sequences of Parvicapsulidae gen. sp. show highest identity (82%) with Parvicapsula minibicornis Kent, Whitaker et Dawe, 1997 infecting salmonids (Oncorhynchus spp.) in fresh water in the western North America. A phylogenetic analysis places P. minibicornis and Parvicapsulidae gen. sp. in a sister clade to the other parvicapsulids (Parvicapsula spp. and Gadimyxa spp.).
基于小亚基核糖体DNA（SSU rDNA）序列，在丹麦的挪威岩虫（Serpulidae科）中产生四触手型放射孢子的一种粘孢子虫被鉴定为微胶囊科的一员。使用检测这种新型粘孢子虫的引物，对来自丹麦和挪威各种海洋鱼类的粘孢子虫样本进行了检测。发现黍鲱（Sprattus sprattus，Linnaeus）和大西洋鲱（Clupea harengus Linnaeus，硬骨鱼纲，鲱科）受到感染。来自这些宿主的这种微胶囊科粘孢子虫的序列始终略有不同（差异为0.8%），但这两种基因型都在挪威岩虫中被发现。通过PCR检测发现一些受感染宿主的肾小管中有双孢子滋养体和一种新型粘孢子虫类型的微小孢子。这些孢子看起来与2007年Køie、Karlsbakk和Nylund描述的Gadimyxa属物种的孢子最为相似，但要小得多。此前已描述过挪威岩虫产生的四触手型放射孢子。在GenBank中，微胶囊科未定种的SSU rDNA序列与1997年感染北美西部淡水鲑科鱼类（Oncorhynchus属物种）的小双角微胶囊虫（Parvicapsula minibicornis Kent、Whitaker和Dawe）的序列具有最高的同一性（82%）。系统发育分析将小双角微胶囊虫和微胶囊科未定种置于与其他微胶囊科物种（微胶囊虫属物种和Gadimyxa属物种）的姐妹分支中。
