Synopsis of the species of Thelohanellus Kudo, 1933 (Myxozoa: Myxosporea: Bivalvulida)

A synopsis of the species of Thelohanellus Kudo, 1933 (Myxozoa: Myxosporea: Myxobolidae) is presented. It includes a total of 108 nominal species. For each species, the most relevant morphological and morphometric characteristics are provided, together with data on the type-host and locality, the site of infection within the host and the original references.     

Synopsis of the species of the genus Myxobilatus Davis, 1944 (Myxozoa: Myxosporea: Myxobilatidae)

A synopsis of the species of Myxobilatus Davis, 1944 (Myxozoa: Myxosporea: Myxobilatidae) is presented. Thirty-nine nominal species are included. The major characteristics and an illustration are given for each species based on the original records.     

Zschokkella hildae Auerbach, 1910: Phylogenetic position,morphology, and location in cultured Atlantic cod

The myxozoan Zschokkella hildae Auerbach, 1910, was detected with a prevalence of 100% in cultured Atlantic cod, Gadus morhua L. aged 1+ from a culture facility on the west coast of Scotland. Sporogonic stages of Z. hildae, plasmodia producing 2–5 mature spores, were located predominantly in the collecting ducts and ureters of the kidney, and spores were present in the urine collected from the bladder. Less frequently, plasmodia were detected in the interstitial tissue of the kidney. The parasite prevalence in cultured fish was considerably higher than reported in wild fish but no obvious signs of pathology were detected. SSU rDNA sequencing and phylogenetic analysis showed that Z. hildae is closely related to a Sinuolinea sp. from the urinary system of turbot, Psetta maxima (L.), and that these two species, together with other myxozoans from the urinary system of marine fish cluster together in a sub-clade of the recognised marine clade of myxozoans. This sub-clade is characterised by a specific linear expansion segment, helix E23_15 in the secondary structure of variable region V4 of the SSU rDNA. Z. hildae and Sinuolinea sp. show extraordinary large linear expansion segment in both V4 and V7 and an important number of complementary base changes in the conservative regions of the SSU rDNA, indicating considerable evolutionary changes in the SSU rDNA of these species when compared with other myxozoans from the marine environment.     

Synopsis of the species of Chloromyxum Mingazinni, 1890 (Myxozoa: Myxosporea: Chloromyxidae)

A synopsis of the species of Chloromyxum Mingazinni, 1890 (Myxozoa: Myxosporea: Chloromyxidae) is presented, including 140 nominal species. For each species the most relevant morphological and morphometric characteristics are indicated. Included are data on the site of infection within the host, the original host and the host locality, plus a full bibliography of the original records for these species. A diagrammatic illustration of a spore of each species is also provided.     

Synopsis of the species of Kudoa Meglitsch, 1947 (Myxozoa: Myxosporea: Multivalvulida)

A synopsis of the species of Kudoa Meglitsch, 1947 (Myxozoa, Myxosporea, Multivalvulida) is presented, including 95 nominal species. For each species the most relevant morphological and morphometric features are indicated in tabulated format. Included are data on the site of infection within the host, the type-host and type-locality, plus a full bibliography of the original records for these species. Molecular data (GenBank accession numbers) are also provided whenever possible.     

A new myxosporean,Zschokkella leptatherinae n. sp. (Myxozoa: Myxidiidae), from the hepatic ducts and gall-bladder of Australian marine fishes

A new myxosporean,Zschokkella leptatherinae n. sp., was found in the hepatic ducts and gall bladder of five atherinid fish species,Leptatherina presbyteroides, Atherinosoma microstoma, Kestratherina brevirostris, K. esox andK. hepsetoides, collected at Dru Point, Margate in south-eastern Tasmania, Australia. This species has a round, ellipsoid or irregular plasmodium. The plasmodium is enclosed by a surface membrane and the cytoplasm is composed of an outer homogeneous ectoplasm and an inner coarse endoplasm with large clear areas, numerous vacuoles and spores which differentiate in the central area of the endoplasm. The characteristic metrical data of the myxosporean are as follows: spores 15.3 × 11.8 m; polar capsules 3.9 × 3.4 m. This is the thirdZschokkella species reported from Australia.     

碘泡科(粘体门:粘孢子纲:双壳目)动物的系统分类学研究

粘孢子虫是一类拥有广泛寄主的后生动物寄生虫,主要寄生于鱼类,并可引发病害,从而受到人们广泛的关注。但其基础研究还不够深入,在分类地位和分类系统方面存在着许多争议。而碘泡科是粘孢子虫最大的一科,其在属级和种级阶元的归属问题上也一直备受争议。此类动物结构简单、种类繁多,依据传统的形态特征进行的分类并不十分准确,借助更为先进的显微技术和以及分子生物学、免疫学等方法的应用,其分类学研究取得了巨大进步。本文从碘泡科的种、属级阶元分类和方法学两个方面对国内外碘泡科物种系统分类学研究的现状进行了综述,对碘泡科各属的归类问题进行了梳理,并对一些容易混淆的种类进行了厘清,同时总结了应用于碘泡虫系统分类研究中的几种方法,以期为该科动物的系统分类和鱼类粘孢子虫病的防治提供基础资料。     

Alternation of Actinosporean and Myxosporean Phases in the Life Cycle of Zschokkella nova (Myxozoa)

ABSTRACT. Experimental evidence has been gathered to show that the life cycle of the myxozoan gallbladder parasite Zschokkella nova Klokacewa, 1914, which infects the fish Carassius carassius , has a complex life cycle with alternation of two hosts (fish and Oligochaeta) and two developmental phases (myxosporean and actinosporean). The gut epithelium of the oligochaete, Tubifex tubifex , exposed experimentally to Z. nova , obtained from C. carassius , became infected with organisms resembling Actinosporea. The spore structure and cube-like network of the interconnected spores is reminiscent of Siedleckiella silesica Janiszewska, 1952, although the spores are very different in size and number of sporoplasm nuclei. The life cycle of Z. nova resembles that of the whirling disease agent Myxosoma cerebralis described by Wolf and Markiw, which also alternates between fish and oligochaete hosts.     

Morphology, molecular data, and development of Zschokkella mugilis (Myxosporea, Bivalvulida) in a polychaete alternate host, Nereis diversicolor

The morphology of Zschokkella mugilis Sitjà-Bobadilla and Alvarez-Pellitero, 1993 (Myxosporea, Bivalvulida) in Nereis diversicolor O. F. Müller, 1776 is described for the first time. The molecular data show that the actinospore has 100% similarity to the myxospore of Z. mugilis. Fully mature actinospores are tri-radiate, the spore body has a small process, and the sporoplasm has 2 inner daughter cells. In the polychaete, the spores of the parasite develop in groups of 8 inside pansporocysts. The schizogony phase takes place in the intestinal epithelium, while gametogony and sporogony occur in the coelom of the polychaete. Observations indicate that mature spores are released only during the polychaete reproductive season. Infection was detected only in the winter and spring. In the Aveiro estuary (Portugal), the overall prevalence of infection of the polychaete was 0.5%.     

Two species of myxozoan parasites (Myxosporea: Bivalvulida), including a new genus,fromPatagonotothen sima (Richardson, 1845) (Pisces: Teleostei) in the southwest Atlantic

A new genus and species of myxozoan parasite,Renispora simae, is described from the gall-bladder of the nototheniid fishPatagonotothen sima (Richardson). Four of 12 fish caught in Stanley harbour in the Falkland Islands in May, 1993 were infected. The new genus is placed in the family Alatosporidae and differs from other genera in this family by the shape of the spore body and the shape and site of adhesion of the membranous extensions to the spore valves. To accommodate the new genus, we propose an amendment to the definition of the family Alatosporidae to include forms with reniform spores.Myxidium baueri Kovaleva & Gaevskaya, 1982 is reported fromP. sima for the first time. It was found in the gall-bladder of one of the same 12 fish caught in Stanley harbour.     

Zschokkella mugilis N. Sp. (Myxosporea: Bivalvulida) from Mullets (Teleostei: Mugilidae) of Mediterranean Waters: Light and Electron Microscopic Description

A new Myxosporea, Zschokkella mugilis n. sp., was found in the gall bladder of several mugilids. It is distinguished from all previously reported Zschokkella from mugilids by the absence of valve ornamentation and from other species by the size of the spores. Prevalence of infection was 62.5% for Mugil capito, 70% for M. cephalus and 64.3% for Liza saliens. Plasmodia with rhizoids attached to epithelial cells appeared to compromise the host as evidenced in light and transmission electron micrographs presented herein. General ultrastructure and disporous sporogenesis of Z. mugilis resembled other Myxosporeans, but sporogonic cells did not seem to be formed in pansporoblasts.     

Synopsis of the genus Mitriostigma (Rubiaceae) with a new monocaulous species from south Cameroon

Mitriostigma monocaule Sonké & Dessein sp. nov., a new Rubiaceae species from south Cameroon is described and illustrated. The novelty is easily separated from the other four Mitriostigma species by its monocaulous growth form, the other species being shrubs, sub-shrubs, or occasionally trees. Another typical character for the species is its supra-axillary inflorescences paired at the nodes. The novelty is related to M. barteri , from which it further differs in the somewhat larger leaves with a more pronounced acumen and a higher number of secondary veins. A first conservation status for the species is given. A synopsis of the genus Mitriostigma with a taxonomic key is also provided.     

The millipede genus Eviulisoma Silvestri, 1910 in Kenya,with descriptions of new species (Diplopoda,Polydesmida, Paradoxosomatidae)

The genus Eviulisoma, the largest among Afrotropical Paradoxosomatidae, currently encompasses 36 species or subspecies, including six new from Kenya: Eviulisoma ngaia sp. n., Eviulisoma ngaiaorum sp. n., Eviulisoma taitaorum sp. n., Eviulisoma taita sp. n., Eviulisoma kirimeri sp. n. and Eviulisoma kakamega sp. n. In addition, Eviulisoma alluaudi Brolemann, 1920 and Eviulisoma silvestre (Carl, 1909) are recorded for the first time beyond their type localities in Kenya and Tanzania, respectively, based on new material from Kenya. A key is given to all ten species of the genus presently reported from Kenya.     

Synopsis of the genus Wrightoporia

The genus Wrightoporia has been amended to include resupinate to pileate polypores with clamped generative hyphae, dextrinoid skeletal hyphae and small, smooth to ornamented amyloid spores. A key is given to the 7 accepted species and W. cinnamomea and W. cylindrospora are described as new. The combination W. subrutilans (Murr.) Ryv. is proposed.     

Species of the genus Chloromyxum Mingazzini (Myxozoa: Myxosporea) infecting burbot (Lota lota L.)

Three different species of the genus Chloromyxum Mingazzini were found in burbot (Lota lota L.) collected in south-west Bohemia (Czechoslovakia). Comparison with existing records revealed that one species could be identified as C. pseudomucronatum Kashkovskiy, 1966. Found in the urinary bladder, it had subspherical spores with fine surface ridges and polysporic plasmodia. The two other myxosporea were established as new species: C. lenorae n. sp. was found in the kidney, renal corpuscles, renal tubules and interstitium, and had ellipsoid spores with surface ridges barely perceptible in the light microscope but clearly revealed by transmission electron microscopy. In the polysporic plasmodia, spores developed in pansporoblasts. C. reticulatum n. sp. was found in the gall bladder. It had polysporic plasmodia and spherical spores (average size 8.1 m in diameter) with a unique surface structures: elevated crests marking off irregular fields which appeared as a reticulum. In five of the fish infected with C. lenorae, bloodstream myxosporean stages of an extrasporogonic cycle were found. Further research is needed to determine whether they are stages of Sphaerospora cristata Shulman, 1962, a species also found in two of the burbot examined, or stages belonging to the Chloromyxum life cycle.