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A new actinospore type Unicapsulactinomyxon (Myxozoa), infecting the marine polychaete, Diopatra neapolitana (Polychaeta: Onuphidae) in the Aveiro Estuary (Portugal)

  • LUÍS F. RANGEL (a1), GÁBOR CECH (a2), CSABA SZÉKELY (a2) and MARIA J. SANTOS (a1) (a3)


This work reports a new type of actinospore, Unicapsulactinomyxon, which exhibits a unique morphological characteristic in that it has a single and large polar capsule (9·3×4·1 μm) (which possesses a longitudinally-folded polar filament) instead of the 3 polar capsules previously described for actinosporeans. The spore has a binucleated sporoplasm and 3 valves, each of which forms a long process. The spore has a total length of 241·3 μm. This parasite develops in groups of 8 inside pansporocysts in the coelomic cavity of the polychaete host. Molecular investigations on the SSU rDNA show that the new actinospore type is most closely related to Enteromyxum species (81–84% similarity). A survey of actinospore infections of the marine polychaete Diopatra neapolitana in 2007 and 2009, in the Aveiro Estuary (Portugal), showed an annual prevalence of 1·0% and 0·3%, respectively.


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*Corresponding author: Universidade do Porto, Faculdade de Ciências, Departamento de Biologia, Rua do Campo Alegre, s/n, FC4, 4169-007 Porto, Portugal. Tel: +351 220402805. Fax: +351 220402709. E-mail:


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A new actinospore type Unicapsulactinomyxon (Myxozoa), infecting the marine polychaete, Diopatra neapolitana (Polychaeta: Onuphidae) in the Aveiro Estuary (Portugal)

  • LUÍS F. RANGEL (a1), GÁBOR CECH (a2), CSABA SZÉKELY (a2) and MARIA J. SANTOS (a1) (a3)


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