Morphology and SSU rDNA sequences of Ortholinea orientalis (Shul’man and Shul’man-Albova, 1953) (Myxozoa, Ortholineidae) from Clupea harengus and Sprattus sprattus (Clupeidae) from Denmark

Abstract

Ortholinea orientalis (Shul'man and Shul'man-Albova 1953) Shul'man 1956 is redescribed from Clupea harengus L. and Sprattus sprattus (L.) (Teleostei, Clupeidae) from the northern Øresund, Denmark. S. sprattus is a new host record. Polysporic plasmodia and most myxospores were found in the ureters of both hosts. The myxospores have external valvular ridges, which were not observed in the original description. The presence of this character causes us to consider Ortholinea clupeidae Aseeva 2000 as a likely synonym of O. orientalis. Ortholinea antipae Moshu and Trombitsky, 2006 from a Black Sea clupeid is also similar and represent a possible synonym. Sequence comparisons and phylogenetic analysis of partial SSU rDNA sequences of O. orientalis reveal closest affinity (82-86% identity) to members of the 'Freshwater Urinary Bladder Clade' sensu Fiala (2006), a clade among the Platysporina containing members of the myxosporean genera Myxobilatus, Hoferellus, Myxidium, Zschokkella and Chloromyxum from freshwater fishes.

Myxobolus groenlandicus n. sp. (Myxozoa) distorting skeletal structures and musculature of Greenland halibut Reinhardtius hippoglossoides (Teleostei: Pleuronectidae)

“…The overall topology of the phylogenetic analysis (Fig. 5) corresponds well with recent analyses of the Myxobolus clade (Griffin & Goodwin 2011, Karlsbakk & Køie 2011, U-taynapun et al 2011, and Clades A, B, and D can also be recognized in a phylogeny of the entire Myxosporea (Fiala 2006). Myxobolus is not monophyletic and this fact has already been well documented (Fiala 2006).…”

Adaptive Radiation and Evolution Within the Myxozoa

“…Furthermore, it is apparent that morphological change may evolve within very short evolutionary timescales since closely related species can demonstrate substantial variation in spore morphologies. For example, each of the closely related species in the freshwater urinary bladder clade (Acauda, Chloromyxum, Hoferellus, Myxidium, Myxobilatus, Ortholinea and Zschokkella) represents highly distinct spore morphotype (Fiala 2006;Karlsbakk and Køie 2011;Whipps 2011) and similar levels of variation amongst myxospore morphologies characterise species in the marine urinary clade Kodádková et al 2014). This is in contrast to rather morphologically uniform myxospores produced in the Ceratomyxa, Kudoa and Sphaerospora clades.…”

“…Li et al 2012;Carriero et al 2013), the marine zschokkellids (Heiniger and Adlard 2014), and the marine Ortholinea spp. (Karlsbakk and Køie 2011). Moreover, freshwater myxosporeans have invaded the terrestrial environment with Soricimyxum fegati infecting shrews (Prunescu et al 2007;Dyková et al 2007Dyková et al , 2011.…”

The life cycle of Ortholinea auratae (Myxozoa: Ortholineidae) involves an actinospore of the triactinomyxon morphotype infecting a marine oligochaete

“…Although they infect fish species belonging to several taxonomic orders, there are more descriptions among the Perciformes (Sarkar 1999;Ali 2000;Abdel-Ghaffar et al 2008;Karlsbakk and Køie 2011). Ortholinea auratae Rangel et al, 2014 was recently described infecting the urinary bladder and posterior kidney of the gilthead seabream, Sparus aurata Linnaeus, 1758, with a prevalence of infection of 51.6 % (Rangel et al 2014).…”