Invertebrate Zoology, 2020, 17(2): 93–117 © INVERTEBRATE ZOOLOGY, 2020

Hyperparasitic spore-forming eukaryotes (Microsporidia, Haplosporidia, and Myxozoa) parasitizing trematodes (Platyhelminthes)

Yu.Ya. Sokolova1,2*, R.M. Overstreet3

1 Institute of Cytology, Russian Academy of Sciences, St. Petersburg, Russia, 4 Tikhoretski Av. St. Petersburg, 194064 Russia. E-mail: [email protected] 2 School of Medicine and Health Sciences, George Washington University, 2300 Eye Str NW, 20037, Washington DC, USA. 3 Gulf Coast Research Laboratory, University of Southern Mississippi, Ocean Springs, Mississippi, USA. E-mail: [email protected]

ABSTRACT: Trematodes serve as outstanding hosts for a variety of parasites. This paper restricts those parasites to three groups of non-related taxa parasitizing trematodes and forming invasive spores similar in external morphology, which is why in the past these three groups of parasitic eukaryotes were united into the taxon “Sporozoa” (Kudo, 1924). (1) Trematode-infecting microsporidia (type Microsporidia Balbiani, 1882: Rozellomycota: Holomycota) are represented by more than 30 species. Among those, the species with sequenced barcode (SSU rDNA) are phylogenetically associated with either microsporidia from invertebrates, as the species of the genus Unikaryon (7 species), or fish microsporidia, as the species of the genera Pleistophora and Ovipleistophora or alike forms (4 species). However, most of the species that we place in the incertae cedis group, are known only by light-microscopy descriptions. Those were attributed by the authors to the genera Nosema (14 species) and Microsporidium (8 species), but in fact their taxonomic affiliation, phylogenetic position, and origin remain unknown. (2) Trematode-infecting haplosporidia (type Haplosporida Caulleri Mesnil, 1899: Ascetosporea: SAR) are represented by only one genus Urosporidium with a broad range of hosts among marine helminths and free-living invertebrates. The literature describes 10 Urosporidium spp. infecting trematodes. (3) Myxosporidia or Myxozoa (subclass Myxosporea Butchli, 1881: class Myxozoa Grasse, 1970: Cnidaria: Holozoa) infect mainly fish. All three species known from trematodes, belong to the genus Fabespora, and, likely, switched to hyperparasitism from fish. These three spore-forming groups demonstrate a diversity of characteristics and group-specific physiological mechanisms in addition to common adaptations responding to similar environmental conditions. These forms developed from genetically dissimilar material and exemplify an amazing power of convergent evolution, a phenomenon A.A. Dobrovolskii and other Russian scholars of parasitology demonstrated for a variety of parasitic groups. How to cite this article: Sokolova Yu.Ya., Overstreet R.M. 2020. Hyperparasitic spore- forming eukaryotes (Microsporidia, Haplosporidia, and Myxozoa) parasitizing trematodes (Platyhelminthes) // Invert. Zool. Vol.17. No.2. P.93–117. doi: 10.15298/invertzool.17.2.01

KEY WORDS: Convergent evolution, Trematoda, Haplosporidia, hyperparasitism, Mi- crosporidia, Myxozoa, Nosema, Pleistophora, Unikaryon, Urosporidium.

Paper is dedicated to the memory of A.A. Dobrovolsky. Статья посвящена памяти А.А. Добровольского. 94 Yu.Ya. Sokolova, R.M. Overstreet

Гиперпаразитические спорообразующие эукариоты (Microsporidia, Haplosporidia и Myxozoa) — паразиты в трематод (Platyhelminthes)

Ю.Я. Соколова1,2, Р.М. Оверстрит3

1 Институт цитологии РАН, Тихорецкий пр., д. 4, Санкт-Петербург, 194064, Россия. E-mail: [email protected] 2 School of Medicine and Health Sciences, George Washington University, 2300 Eye Str NW, 20037, Washington DC, USA. 3 Gulf Coast Research Laboratory, University of Southern Mississippi, Ocean Springs, Mississippi, USA, E-mail: [email protected]

РЕЗЮМЕ: Трематоды хорошо известны как хозяева разнообразных паразитических организмов. В настоящей статье рассмотрены представителей трех неродственных таксонов эукариот, представители которых паразитируют в трематодах и формиру- ют инвазионные споры, сходные по внешней морфологии, из-за чего в прошлом эти три группы паразитических эукариот объединялись в тип Sporozoa (Kudo, 1924). (1) Микроспоридии (тип Microsporidia Balbiani, 1882: Rozellomycota: Holomycota) пред- ставлены более чем 30 видами. Виды с отсеквенированным баркодом (участок МС рДНК) филогенетически связаны либо с микроспоридиями беспозвоночных, как виды рода Unikaryon (7 видов), либо с микроспоридиями рыб, как виды родов Pleistophora и Ovipleistophora (4 вида). Однакао большинство видов, которые мы поместили в группу incertae сedis, известны лишь по светооптическим описаниям и отнесены авторами описаний к родам Nosema spp. (14 видов) и Microsporidium spp. (8 видов). (2) Гаплоспоридии (тип Haplosporida Caulleri et Mesnil, 1899: Ascetosporea: Sar) представлены только одним родом Urosporidium, имеющим широкий спектр хозяев среди морских беспозвоночных, как паразитических, так и свободноживу- щих. В литературе описано10 видов, заражающих трематод. (3) Миксоспоридии или Myxozoa (п/класс Myxosporea Butchli, 1881: класс Myxozoa Grasse, 1970: тип Cnidaria: Holozoa), заражают, главным образом, рыб. Все 3 вида, известные из трематод, принадлежат к роду Fabespora, и, очевидно, перешли к гиперпаразитированию с рыб. Эти три генетически неродственные группы «Sporozoa» демонстрируют разнообраз- ные признаки и физиологические механизмы, специфичные для каждой группы, но также и сходные адаптации к паразитизму, выраженные, в частности, в сходстве морфотипов и некоторых особенностей патогенеза. В целом, описанные группы эукариотических микроорганизмов представляют собой наглядный пример конвер- гентной эволюции — феномена, многократно описанного А.А. Добровольским и другими представителями Российской школы паразитологии на различных группах паразитов. Как цитировать эту статью: Sokolova Yu.Ya., Overstreet R.M. 2020. Hyperparasitic spore-forming eukaryotes (Microsporidia, Haplosporidia, and Myxozoa) parasitizing trematodes (Platyhelminthes) // Invert. Zool. Vol.17. No.2. P.93–117. doi: 10.15298/ invertzool.17.2.01

КЛЮЧЕВЫЕ СЛОВА: конвергентная эволюция, Trematoda, Haplosporidia, гиперпа- разитизм, Microsporidia, Myxozoa, Nosema, Pleistophora, Unikaryon, Urosporidium. Hyperparasitic Microsporidia, Haplosporidia, and Myxozoa parasitizing trematodes 95

Introduction primary hosts of the hyperparasites. As an example, a parasite that we are not This review is dedicated to Andrey Aleksan- treating in detail (Overstreet, 1976b), we note a drovich Dobrovolskii, a brilliant university pro- diplomonad flagellate (Hexamita sp.) in the fessor having a bright personality, a man of the intestine of Crassicutis archosargi (Digenea) highest culture and integrity, and an outstanding but not in its fish host, the sheepshead (Archo- parasitologist specializing in trematodes. His sargus probatocephalus), similar to a larger fascinating lectures on protistology, inverte- species of Hexamita in reproductive systems brate zoology, parasitology, and particularly on and eggs of Deropristis inflata (Digenea) in the trematode life cycles, made listeners fall in love American eel, Anguilla rostrata, from near with the creatures that he discussed as well as Woods Hole, Massachusetts (Hunninen, Wich- with Nature and Science in general. These lec- terman, 1938). Several authors (e.g., Dollfus, tures inspired students of several generations, 1946; Overstreet, 1976b) discuss these other including the first author of this paper, to remain protists. A few trematodes of herbivorous hosts in the field of parasitology throughout their in Mississippi, such as the common mullet small lives. This paper contains the overview of the haploporids (< 1 mm long) Xiha fastigata (pre- current state of research on eukaryotic parasites viously known as Dicrogaster f.) and Saccocoe- of trematodes, thus covering subjects that al- lioides beauforti (recently referred to as Culu- ways were in the focus on Prof. Dobrovolskii’s wiya b.) contain motile bacteria in their excreto- interests, namely the biology of trematodes and ry vesicles. A couple of attempts to extract the the phenomenon of hyperparasitism. The fact bacteria using capillary tubes to collect, culture, that large parasites have smaller parasites and and identify (or sequence) were unsuccessful that they yet have smaller parasites has thrilled (RMO, unpublished data), but we encourage biologists for centuries, possibly before pointed others to achieve this with the same or other out in an early poem (Swift, [1733] 1910). In hyperparasitic bacteria and techniques. The conjunction with the microscope’s invention, a bacteria in the haploporids seem to be non- mathematician (De Morgan, 1915) developed a harmful symbionts unlike the bacterium Ed- rhyme based on Jonathan Swift’s poem, “Big wardsiella ictaluri in the metacercaria of the fleas have little fleas upon their backs to bite’em; diplostomoid Bolbophorus damnificus, which and little fleas have lesser fleas, and so ad readily kills the hyper-host (commercial catfish, infinitum.” The first comprehensive review of Ictalurus punctatus) and unlike other discussed the known literature on hyperparasitic associa- associative bacteria (Overstreet, Lotz, 2016). tions among helminths including parasites of The purpose of this publication is to discuss trematodes, appeared in 1946 (Dollfus, 1946). the non-related spore-forming, eukaryotic para- Trematodes seem to provide an acceptable sites in trematodes, namely 1) Microsporidia home to a variety of eukaryotic parasites, like (type Microsporidia Balbiani, 1882: Rozello- microsporidia, myxozoa, haplosporidia, ciliates, mycota: Holomycota), 2) Haplosporidia (type flagellates, and amoebae as well as bacteria and Haplosporida Caulleri, Mesnil, 1899: Asceto- viruses. Complicated life cycles of trematodes sporea: Sar), and 3) Myxosporidia or Myxozoa that, in the course of their lifespans, infect (subclass Myxosporea Butchli, 1881: class several hosts belonging to various trophic lev- Myxozoa Grasse, 1970: Cnidaria: Holozoa). In els, providing exceptional opportunities for the fact, the World Register of Marine species parasites to hitchhike between various inverte- (WoRMS) places them in three kingdoms (Fun- brates and vertebrates, particularly those in gi, Phylum Microsporidia; Chromista, Phylum marine and freshwater ecosystems. Parasitizing Cercozoa; and Animalia, Phylum Cnidaria). trematodes should facilitate host-switching, From recent phylogenies in the Tree of Life spreading infections throughout the habitat, and (Fig. 1) joining plants and animals, the first horizontal gene transfer among secondary and group (Microsporidia) shows a close relation- 96 Yu.Ya. Sokolova, R.M. Overstreet

crosporidia has yet to be established. Recent studies based on molecular data revealed a few peculiar phylogenetic associations of trema- tode-infecting microsporidia from crustacean and fish hosts with overlapping habitats, partic- ularly marine and estuarine ones (Fig. 2). They suggest trophic transfer of microsporidian spe- cies, particularly those of the Clade 5 “Marino- sporidia” (Vossbrinck et al., 2014; Stentiford et al., 2017a; Sokolova, Overstreet, 2018; Bojko et al., 2020). Presumably, some microsporidian taxa from the Clade 5 might have exploited life strategies of various parasites, including trema- todes, to gain additional opportunities for trans- Fig. 1. Tree of Life (modified from Adl et al., 2019) mission either within polyxenous life cycles or demonstrates phylogenetic position of Microsporidia through predation of the infected host tissues by (Holomycota; Rozellamycota), Haplosporidia (SAR, Ascetosporea), and Myxosporidea (Holozoa, Cni- a potential alternative host (Stentiford et al., daria). 2017a). However, direct evidence of a multi- Рис. 1. Дерево Жизни (по Adl et al., 2019) демон- host invertebrate-fish parasite life cycle has стрирует филогенетическое положение Microspo- been demonstrated only for Paranucleospora ridia (Holomycota; Rozellamycota), Haplosporidia theridion, which uses a salmonid fish (Atlantic (SAR, Ascetosporea) и Myxosporidea (Holozoa, Cnidaria). salmon, Salmo salar, or rainbow trout, Onco- rhynchus mykiss) as an intermediate host and an ship to Fungi; the second, Haplosporidia, is ectoparasitic copepod (Lepeophtheirus salmo- associated with Foraminifera and brown algae; nis or Caligus elongates) as a definite host and the third, Myxosporidia represents highly (Freeman et al., 2003; Nylund et al., 2010; reduced coelenterates (Adl et al., 2012, 2019). Freeman, Sommerville, 2011). We stress that However, in early phylogenies, the orders Asc- hyperparasitism has been commonly reported etosporea (including Haplosporidia), Microspo- among “higher” microsporidia (Phylum Mi- ridia, and Myxozoa were united in the class crosporidia; Class Microsporea, sensu Sprague, “Sporozoa” (Kudo, 1924), not accepted nowa- 1977). Noteworthy that metchnikovellids (Phy- days. From the point of ecology, “Sporozoa” lum Microsporidia; Class Rudimicrosporea, truly makes sense. The representatives of these Order Metchnikovellida sensu Sprague, 1977), groups share marine (or rarely freshwater) hab- the basal and diverged group of the phylum itats, produce environmental spores that some- Microsporidia, are all gregarine-infecting hy- times can hardly be distinguished from each perparasites (Sokolova et al., 2013, 2014). In other by the naked eye, infect the same host addition to trematodes, hyperparasitic microspo- species, and often exhibit identical pathology. ridia also infect Myxozoa, both myxosporean All together, these three major taxa reflect par- developmental sequences from fish (Kudo, 1939; allel evolutionary adaptations to the environ- Diamant, Paperna, 1985) and actinosporian se- ment, which in the case of hyperparasites in- quences from oligochaetes (Morris, Freeman, cludes the habitat; primary (helminth) host; and 2010); paramyxids (Stentiford et al., 2017b); the secondary host, or hyper-host (host of the cestodes (Dissanaike, 1957; Canning, Gunn, helminth). 1984; Poddubnaya et al., 2006); and parasitic copepods (Nylund et al., 2010; Freeman, Som- Microsporidia merville, 2011). Hitchhiking in other parasites, The role of trematodes in host-switching and and particularly trematodes, may be considered in overall shaping the evolutionary tree of Mi- as one potential route of transmission and radi- Hyperparasitic Microsporidia, Haplosporidia, and Myxozoa parasitizing trematodes 97

Fig. 2. Phylogenetic tree combined from several SSUrDNA-based analyses (Stentiford et al., 2017a; Lovy, Friend, 2017; Sokolova, Overstreet, 2018) of the fragment of the Clade V (Marinosporidia). This class contains mostly fish-infecting species (fish icons), but also several peculiar phylogenetic associations (exclamation marks) suggesting presumable role of hyper-parasites, like trematodes, in potential host switching between fish and crustacean hosts (shrimp icons). Species parasitizing trematodes, are indicated by asterisks. The outgroup Clade IV contains the only known microsporidium with a polyxenous fish- crustacean lifecycle (Desmozoon lepeophtherii). Рис. 2. Филограмма, обобщающая несколько филогенетических анализов на основании МС рДНК (Stentiford et al., 2017a; Lovy, Friend, 2017; Sokolova, Overstreet, 2018), демонстрирует связи внутри Клады V (класс “Marinosporidia”). Эта клада состоит, в основном, из видов, заражающих рыб (изображение рыбы), но также содержит несколько странных филогенетических ассоциаций (вос- клицательные знаки), которые предполагают роль гиперпаразитов (возможно, трематод) в смене хозяев с рыб на ракообразных (изображение креветки) и обратно. Виды, паразитирующие у трематод помечены звездочками. Внешняя группа, Клада IV, содержит единственный вид микроспоридии (Desmozoon lepeophtherii) с подтвержденным поликсенным (рыба–ракообразное) жизненным цик- лом. 98 Yu.Ya. Sokolova, R.M. Overstreet ation of microsporidia (Stentiford et al., 2017a). in the first intermediate host, a mollusk, or in Potential host-switching among infected trema- metacercariae developing in the second inter- tode hosts or between trematodes and their hosts mediate host which could be a mollusk, crusta- might have been facilitated by an exceptional cean, or fish. Microsporidia and microsporidia- ability of trematodes to suppress host innate infected worms have never been isolated from immune responses. Mechanisms of this phe- birds, the definitive host of many marine species nomenon, like suppression of macrophage acti- of trematodes (Shigina, 1986). vation through inhibiting Toll-like receptors The genus Unikaryon Canning, Lai et Lie, (TLRs) and inhibition of inflammatory respons- 1974 with its type-species, U. pyriformis (see es by parasite glycans, have been recently re- Canning et al., 1974), is composed of special- vealed and intensively studied (Mabbott, 2018). ized parasites of helminths, mostly trematodes, Thus infection with trematodes potentially could but also cestodes (Sene et al., 1997). Currently, enable penetration of generally opportunistic it includes two species of trematodes known microsporidia by creating immune-privelage from fishes and three species known from mol- niches. lusks (Azevedo, Canning, 1987). In addition, To our knowledge, as many as 34 species of two new yet undescribed species that share microsporidia have been reported from digene- morphological similarity and >95% of SSrDNA an hosts (Table 1), and this number continually sequence identify with U. legeri, have been grows: Victor Sprague in his comprehensive for recently isolated from crab intermediate hosts the time “Annotated list of species” (Sprague, (RMO, YYS, unpublished) (Table 1). All spe- 1977) mentioned only 17 microsporidia infect- cies of Unikaryon, except one, are known from ing trematodes. Given the facts that the field has larval stages, predominantly encysted metacer- been understudied and most findings of mi- caria (see Table 1 for references). Probably, crosporidia in trematodes are fortuitous, such a many species, infecting metacercariae in inver- large number indicates that microsporidian in- tebrate hosts and currently attributed to Nosema fections in trematodes are fairly common in (e.g., N. rhionica and N. strigeoideae) and to nature. Seven of the described species belong to Microsporidium (e.g., M. spelotremae), belong the genus Unikaryon, four belong to the two to Unikaryon. The distinguishing morphologi- closely-related genera of fish microsporidia, cal characters of Unikaryon spp. include the Pleistophora and Ovipleistophora, and the re- presence of prespore diplokaryotic stages in the maining 23 species occur distributed among the life cycle, disporoblastic sporogony, and uninu- genera Nosema (14 species) and a collective cleate spores with large posterior vacuoles. taxon Microsporidium (8 species). However, Spores are often arranged in pairs within a we place them into an incertae sedis group, as sporophorous vesicle membrane, which might they are described on the basis of light micro- be either robust or fragile, and occasionally scopic observations only that is not sufficient reside in voluminous parasitophorous vacuoles for discrimination. In contrast, electron micro- individually or in pairs (Canning, Nicholas, scopic observations exist for two of the four 1974) (Fig. 3). species of Pleistophora-Ovipleistophora and A few microsporidia infecting trematodes for all seven species of Unikaryon. Unfortu- belong to the closely-related genera Pleistopho- nately, GenBank-accessible SSUrDNA sequenc- ra and Ovipleistophora. Representatives of these es currently exist for only two species of mi- genera predominantly infect adult trematodes crosporidia parasitizing trematodes (U. legeri, parasitizing vertebrate hosts. Species in both KX364285 and O. diplostomuri KY809102). genera produce multinucleate plasmodia trans- Consequently, rDNA-based phylogenetic rela- forming into sporophorous vesicles with multi- tionships of most species infecting trematodes ple dimorphic micro- and macrospores (Table remain obscure. Most described species are 1). These microsporidia seem to have switched known from rediae and sporocysts developing to trematodes from fishes and potentially could Hyperparasitic Microsporidia, Haplosporidia, and Myxozoa parasitizing trematodes 99 . ., ., et al et al трематод

., 2017a ., 2017a 1974 Canning Canning Shigina, 1972; Grobov, 1986 Shigina, 1912; Dollfus, Nicho- Canning, 1974; Aze- las, Canning, vedo, 1987; Stentiford et al Canning, 1977 Madhavi, YYS, RMO, unpublished YYS, RMO, unpublished 1983 Canning Canning микроспоридий

Locality References West Malaysia Moscow Region, Russia France, Great Britain, Portugal Andra Pradesh, India Tampa Bay, USA Florida, Molasses Florida,Key, USA Devon, Devon, England Виды 1. Таблица coils coils 3.8 x 2.7; Pt 150 3.8 x (>15 coils) 1.8; 4–5 3.5 x coils 1.7; Pt 35; 2.9 x 6–6.5 coils; 2.7; Pt 30; 3.5 x 4–5 coils 1.3; 6 coils 2.3 x 1.2; 4 coils 2.4 x 5 x 2.8; 17–21 5 x coils Spore size; Pt* No µm; length, 4 Table 1. Microsporidia species described in digenean hosts. + , ,

, (Brachyura), (Brachyura), Planorbis Planorbis Gobio gobio Gobio Cyprinus carpio; carpio; Cyprinus

and other marine marine other and , ; ; Lebistes reticulatus; reticulatus; Lebistes melastigma Hyper-host Hyper-host (Gastropoda), (Gastropoda), spp. spp. Canning, Foon et Lie, 1974 Salmo irideus Rutilus rutilus Lymnea rubigenosa Lymnea exustus Indoplanorbis snails freshwater (Gastropoda), spp. (Perciformes: freshwater Salmoniformes), fishes; Exp: Lymnea eduli Cardium (Bivalvia) molluscs Aplocheilus freshwater (Cyprinodontiformes), fishes herbstei Panopeus crabmarine transverses Pachygrapsus crab marine (Brachyura), Radix peregra Radix planorbis planorbis snailsfreshwater

Unikaryon ,

D. Echinostoma Echinostoma , ,

acercariae;

; Redia, cercaria; Host; Host; (Microphallidae); (Microphallidae);

sp. (Microphallidae); (Microphallidae); sp. sp. D. parspathaceum parspathaceum D. Fasciola hepatica Fasciola Tissue tropism tropism Tissue , Life cycle stage; i (Echinostomatidae); Exp**: Exp**: i (Echinostomatidae); indistinctum (Diplostomatidae); Sporocysts, cercariae, metacercariae; parenchyma, tegument, lysis wall cyst Schistosoma mansoni Schistosoma Echninoparyphium dunni Echninoparyphium somateriae, Gymnophalus minutus Meiogymnophallus Met (Gymnophallidae); Parenchyma fasciatusi Allocreadium parenchyma Adult; (Allocreadiidae); recurvatum Echinoparyphium sporocysts, Redia, (Echinostomatidae); germinal parenchyma, metacercaria; Exp: tissues; Microphallus audy mansoni Shistosoma parenchyma spathaceum Diplostomum Encysted metacercaria; parenchyma Diacetabulum Encysted metacercaria; tegument

sp.2 sp.1 sp.1 (Dollfus, (Dollfus, Parasite Parasite *Pt — polar tube, figures correspond to the length in micrometers; length; **Exp experimental infection. Canning et et Canning 1977 Madhavi, Barker, Canning, Hammond, 1983 Nicholas, U. piriformis et Lai Canning, 1974 (type- Lie, species) diplostomi U. U. legeri 1912) KX364285 allocreadii U. slaptonleyi U. Unikaryon Unikaryon Shigina et Grobov, Grobov, et Shigina 1972 100 Yu.Ya. Sokolova, R.M. Overstreet ). ., et al ., 1966 et al продолжение Paperna Paperna 1978 Guyénot, Guyénot, 1924; Naville, 1975; Canning Sprague,1977 Lie Friend, Lovy, 2017 1 ( Table 1 (continued). Таблица Locality References Atlantic, Atlantic, Mediterra- nean Sea Central (State Malaya Negri of Sembilan) Italy, Poland, Italy, Belgium, Switzerland Jersey, New USA Spore size; Pt* 3.7 x 1.7; Pt. 250; 3.7 x 17–19 coils Multicellular Multicellular plasmodia. 3–4. Microspores: 6–7; Pt Macrospores: 70 4.3 x Microspores: in 1 2.5, 6–9 coils in Macrospores row; SPV: 7.5 x separate in 4.7; 19–43 coils; 1–4 rows length, µm; No coils coils No µm; length,

Chalcides Chalcides (Reptilia: (Reptilia: sp., sp., (Perciformes), Ovipleistophora (Gastropoda) (Gastropoda) not available Data Rana temporaria and Lacerta (Mugiliformes), marine marine (Mugiliformes), , Hyper-host (Reptilia: Squamata) Squamata) (Reptilia: Emys orbicularis Emys

Pleistophora (Amphibia: Anura) frog frog Anura) (Amphibia: Liza ramada fish macrochirus Lepomis fishfreshwater Natrix natrix Natrix tridactylus snakes; turtle; Testudines) rubiginosa Lymnea , acercarial spp. spp. Host; Host; spp. (26 species), species), (26 spp. Tissue tropism tropism Tissue Life cycle stage;

Heterophyes heterophyes Met (Heterophyidae); capsule minimum Posthodiplostomum (Diplostomatidae); Metacercaria cyst of encapsulation fibrotic and wall Echinostoma Echinoparyphium Sporocysts, (Echinostomatidae); rediae, cercariae Encyclometra bolongensis Telorchis ercolanii ercolanii Telorchis Adult; (Telorchiidae); generalized parenchyma,

. . sp sp Lovy

) Parasite Parasite Glugea Pleistophora Pleistophora ( Pleistophora Pleistophora Ovipleistophora diplostomuri 2017 Friend, et KY809102 Lie, Basch, 1966 Umathevy, danilewskyi danilewskyi 1895 Pfeiffer, Paperna, Sabnai, Sabnai, Paperna, 1978 Castel, Hyperparasitic Microsporidia, Haplosporidia, and Myxozoa parasitizing trematodes 101 ). et ., 2004 et al продолжение ., 1975; Higby ., 1975; Higby 1 ( ., 1979. Table 1 (continued). Levron Levron 1964 Sprague, 1922; Brumpt, 1973; Hussey, 1974; Voronin, 1975; Canning, 1986 Shigina, Basch, Canning, 1972; 1968; Canning, 1970; Basch, Lie, 1975; Colley Colley, et al Madhavi, Canning, 1977 al Таблица & Locality References Corsican Mediterranean Coast, France Atlantic, Chesapeake Bay, USA Maryland, Lake France; Paris, Michigan, USA; Lake Dolgoye, Russia Leningrad, Malaysia India Balbiani, 1884 Spore size; Pt* Microsporidium 2.1 x 1.4; 6–7 coils 1.4; 6–7 coils 2.1 x 1.7 3 x 2.8 4.7 x 2.31; 10–12 3.9 x coils 4.9; Pt 190; 7.9 x c.12 coils length, µm; No coils coils No µm; length,

sp., sp.,

L. ; melastigma Naegeli, 1857” and Hyper-host Hyper-host Diplodus annularis Diplodus fish marine (Perciformes), Crassostrea virginica (Bivalvia) limnosa Limnea Succinea palustris, campanulatum Helisoma (Gastropoda) similaris Bradybaena (Gastropoda); maculates Conocephalus Orthoptera) (Insecta: Aplocheilus (Cyprinodontiformes), fishfreshwater Nosema

but used as the legitimate name of a collective group for unidentified species, or if genus new species U.

hoppers); hoppers); sensu stricto

Host; Host;

Tissue tropism tropism Tissue Life cycle stage; Incertae sedis groups: “ Eurytrema pancreaticum Eurytrema Sporocysts, (Dicrocoelidae); cercariae (in snails), (inmetacercariae grass parenchyma; peripheral tegument, gallinum Postharmostomum (Brachylaimoidae); similar pathogenesis in snails fasciatusi Allocreadium Adult; (Allocreadiidae); with Co-infection parenchyma; allocreadium Diphterostomum brusinae brusinae Diphterostomum gut Adult; (Zoogoidae); epithelium, connective tissue cuculus Bucephalus (Bucephalidae); Cercariae, metacercariae Cercaria, Echinostomatidae; walls metacerariae, cyst is not an available name

Parasite Parasite Microsporidium

Perezia & Canning et Basch, Basch, et Canning 1968) et Canning 1977 Madhavi, Nosema diphterostomi Levron, Ternengo, Toguebaye et 2004 Marchand, N. dollfusi 1964 Sprague, N. echinostomi 1922 Brumpt, N. eurytremae 1972 Canning, (= helminthorum gigantica N. cannot be recognized. 102 Yu.Ya. Sokolova, R.M. Overstreet ). ., et et et al ., 1974 ., 2014 продолжение Canning, Canning, 1980 Olson, Canning al Voronin, Voronin, 1974 Levron Levron 2005 Toguebaye al Voronin, 1974 1 ( Table 1 (continued). Таблица Locality References Pacific, San Diego, USA West Caucasus, Caucasus, West Kura River Basin Moscow Moscow Region, Russia; freshwater basins Corsican Mediterranean Coast, France near Atlantic, Dakar, Senegal brackets in italic font. Spore size; Pt* 3.5 x 1.5; 10 coils 1.5; 10 coils 3.5 x 4.9 x 3.0; Pt 100 > 4.9 x USA Michigan, 1971 Hussey, 4.3 x 2.9; Pt 190 4.3 x 3.2 x 2.5; 16–17 coils 2.5; 16–17 coils 3.2 x 2.6; 11–16 coils 3.6 x 1.6 3.1 x Malaysia West length, µm; No coils coils No µm; length,

(Gastropoda) (Gastropoda) 2.3 4.4 x

octolineatum

Hyper-host Hyper-host Leuresthes tenuis Leuresthes fish marine (Atheriniformes), Stagnicola emarginata Stagnicola (Gastropoda) Melanopsins praemorsa praemorsa Melanopsins (Gastropoda) Diplodus annularis Diplodus fish marine (Perciformes), Parapristipoma (Perciformes) ,marine fish rubiginosa Lymnaea (Gastropoda) palustris Lymnaea

)

(Monorchiidae); (Monorchiidae); Host; Host; Tissue tropism tropism Tissue Life cycle stage; Cercaria rhionica Cercaria Lepocreadium manteri Lepocreadium female Adult; (Lepocreadiidae); gonads Diplostomum flexicaudum Diplostomum and Mother (Diplostomatidae); cercariae, sporocysts, daughter metacercariae; Exp. Mesostephanus appendiculatus appendiculatus Mesostephanus (syn. (Cyathocotylidiae); Sporocysts, Sporocysts, (Cyathocotylidiae); cercariae; parenchyma Monorchis parvus Monorchis epithelium uterus gut, Adult; magnatestis Podocotyloides parenchyma Adult; (Opecoelidae); Plagiorchiidae; Rediae, cercariae; parenchyma Sporocysts, Plagiorchiidae; cercariae, metacercariae; parenchyma

@ ?)

Cannin Cannin

Levron. Levron. @ ?) Voronin Voronin Canning, Canning, Parasite Parasite Unikaryon Our conjectures regarding the parasite species basing on published data morphology, hosts and pathogenesis are indicated in @ strigeoideae

Unikaryon Hussey, 1971 Hussey, ( N. lepocreadii lepocreadii N. monorchis N. Ternengo, Toguebaye 2005 Marchand, et podocotyloides N. Tonguebaye, et Diagne, Quillichini, 2014 Marchand, rhionica N. N. N. vasicola 1974 Lie, et Lai xiphidiocercariae N. 1974 Voronin, et Olson, 1980 Olson, et 1974 ( Hyperparasitic Microsporidia, Haplosporidia, and Myxozoa parasitizing trematodes 103 ). ., ., et al et al продолжение Palmieri Palmieri 1978 Palmieri 1978 1936; Martin, 1986 Shigina, Canning, Basch, Basch, Canning, 1968. Lutz, Splendore, Splendore, Lutz, 1908; Shigina, 1986 Smith, 1959; Smith, 1986 Shigina, Ginetsinskaya, 1968 1 ( Table 1 (continued). Таблица Locality References brackets in italic font. Woods Hole Hole Woods Region, Massachusetts, USA Near Kuala Lumpur, Malaysia Brazil Brazil Ann Arbor Arbor Ann ichigan Area, Khar’Kov, northeast Ukraine Spore size; Pt* Data not available not available Data 3.5 x 2.0; Pt 75 3.5 x 2 x1 (in groups and and groups (in 2 x1 individual) Data not available not available Data Data not available not available Data USA not available Data USA not available Data length, µm; No coils coils No µm; length,

? (Anura) frog (Anura) (Reptilia: (Reptilia:

(Gastropoda) (Gastropoda) (Gastropoda) sp. (Gastropoda), (Gastropoda), sp. Hyper-host Hyper-host Succinea Succinea snail marine Bradybaena similaris similaris Bradybaena (Gastropoda) Ferressia novangliae Ferressia freshwater (Gastropoda), limpet Lymnaea auricularia auricularia Lymnaea rubiginosa auricularia Lymnaea rubiginosa natrix Natrix Serpentes) Squamata: Bufo marinus Bufo marinus

; Adult; ; Adult; sp. sp. same sp.; Host; Host; (Cladorchiidae) ; Sporocyst, redia, redia, ; Sporocyst, Tissue tropism tropism Tissue Life cycle stage; Digenea; Sporocysts Sporocysts Digenea; temperatus tissues in limpet Also cercaria; Fasciola gigantea, Echinostoma Echinostoma gigantea, Fasciola Tracheophillus audyi, (Fasciolidae, Echinostomatidae); Sporocysts, cercariae; Digestive and glands reproductive Echinostoma gigantea, Fasciola Tracheophillus audyi, pathogenesis Megalodiscus cloacicola Paralepoderma larvae (Plagiorchiidae); Eurytrema pancreaticum, pancreaticum, Eurytrema gallinum Postharmostomum (Brachylaimidae); Sporocysts, cercaria, and metacercaria Glypthelmins linguatula Glypthelmins cells) (yolk gonads sp. sp.

@

) sp. 1 sp. 2 sp. @ Microspori- ) Parasite Parasite Our conjectures regarding the parasite species basing on published data morphology, hosts and pathogenesis are indicated in @ microspores of microspores Martin, 1936 Martin, 1959 Smith, Nosema Lai, Palmieri, 1978 Cali, Sullivan, Nosema Lai, Palmieri, 1978 Cali, Sullivan, Perezia helminthorum Basch, et Canning 1968 ( dium? Microsporidium Microsporidium dobrovolskyi M. 1968 Ginetsinskaya, distomi M. ( Pleistophora-like species? 104 Yu.Ya. Sokolova, R.M. Overstreet ). ., et al .,1925; al

et продолжение 1 ( Table 1 (continued). Schäller, 1959; Schäller, 1986 Shigina, Undeen, Vavra, Canning, 1970; Lai, 1980; Franzen 2006 Guyénot Guyénot Canning, 1975 Canning, Guyénot, Naville, Naville, Guyénot, 1986 1924; Shigina, Таблица brackets in italic font. Locality References Eastern Germany; Eastern Germany; basinsfreshwater Exp: England England Exp: Italy Italy A. 3.5 x 2; 9–11 3.5 x Spore size; Pt* 2.3–3.4 x 1.1–1.5 u 2.3–3.4 x Regular spores of of spores Regular algerae coils 3.5 x1.5 Pt 106 3.5 x1.5 England France, 2–2.5 x1; (in groups groups (in 2–2.5 x1; individual) and length, µm; No coils coils No µm; length,

(Squamata), (Squamata), sp. sp. Hyper-host Hyper-host Experimental infection infection Experimental

Tropidiscus (Gastropoda) Carcinus maenas maenas Carcinus (Brachyura) Biomphalaria glabrata glabrata Biomphalaria freshwater (Gastropoda), snail Natrix natrix Natrix snake fresawater ; ;

Host; Host;

sp.; Metacercaria: sp. (3 species); Tissue tropism tropism Tissue Life cycle stage; Fasciola hepatica Fasciola Cercaria cercariae and Sporocysts Spelotrema Spelotrema generalized parenchyma, Telorchis ercolanii Telorchis (Telorchiidae); epithelium; tegument Adult; parenchyma Schistosoma mansoni Schistosoma Sporocysts Exp. Exp. ,

sp.

@ ) algerae Nosema

( ) @ )

Parasite Parasite Our conjectures regarding the parasite species basing on published data morphology, hosts and pathogenesis are indicated in @ microspores of microspores ? Unikaryon Schäller, 1959 Schäller, M. ghigii M. ( Pleistophora-like species? Microsporidium M. spelotremae et Naville Guyénot, 1925 Ponse, ( Anncaliia (Vavara et Undeen, 1970) Brachiola Hyperparasitic Microsporidia, Haplosporidia, and Myxozoa parasitizing trematodes 105

Fig. 3. Two new microsporidia of the genus Unikaryon isolated from trematodes infecting crabs: a–e — Uniklaryon sp.1 from encysted metacercaria of Microphallus sp. in Panopeus herbstii from Tampa Bay, Florida, USA; f — Unikaryon sp. 2 from encysted metacercaria of Diacetabulum sp. in Pachygrapsus transversus from Molasses Key, Florida, USA. a — the infected metacercarian cyst (IC) is much larger than uninfected ones (UC). Unstained smear, light microscopy, DIC; b — infected (IC) and uninfected cysts (UC) on thick sections stained with methylene blue, bright field light microscopy; c — infected metacercaria in scanning electron microscope: the parasitophorous vacuole (PV) is tightly packed with spore duplets. d — a duplet of spores enclosed in sporophorous vesicle membrane (arrow), at higher magnification, transmission electron viroscopy (TEM); e — parasitophorous vacuole (PV) filled with sporophorous vesicles, TEM; f — Unikaryon sp. 2 exclusively infects submerged secretory epithelial cells in the trematode tegument. Arrow indicates the limits of the sporophorous vesicle that encloses two spores, TEM (membranes are poorly preserved because of initial fixation in paraformaldehyde). Рис. 3 Два новых вида микроспоридий рода Unikaryon из трематод, заражающих крабов: a–e — Uniklaryon sp.1 из инцистирующихся метацеркарий Microphallus sp. в Panopeus herbstii из Tampa Bay, Florida, USA; f — Unikaryon sp. 2 из инцистирующихся метацеркарий Diacetabulum sp. в 106 Yu.Ya. Sokolova, R.M. Overstreet play a role in distribution of microsporidia among blasts of metacercarial capsules of a heterophy- fishes, snakes, amphibians, and reptilians asso- id trematode (Heterophyes heterophyes) in the ciated with an aquatic habitat and often hosting thinlip grey mullet, Chelon (=Liza) ramada trematode parasites. For example, Pleistophora (Paperna et al., 1978). The authors assigned the danilewskyi infects the trematode Telorchis er- microsporidium to Pleistophora sp., but more colanii from the intestine of the grass snake, likely it is in fact conspecific with O. diplosto- Natrix natrix, but also was recorded from snake muri (Lovy, Friend, 2017). The unique tropism tissues free of trematodes, as well as from liz- of Oviplestophora spp. may reflect the opportu- ards, turtles, and frogs that share habitats with nistic nature of microsporidia. Oviplestophora the grass snake (Guyénot, Naville, 1924; Can- mirandella, the type-species (Pekkarinen et al., ning, 1975). One of four species identified as 2002), infects fibroblasts in ovaries and testes Pleistophora sp. was isolated from a gastropod that are known as immunologically privileged and infected encysted metacercaria (Lie et al., organs. O. diplostomuri, in turn, infects fibro- 1966). Since ultrastructural studies were not blastic formations encapsulating the metacer- conducted, and life cycle and morphological carial cyst wall protected by trematode-induced details were omitted from the original descrip- immunosuppression. Hence, in some ways these tion, we strongly believe that this species was two species share similar tissue tropism, both misidentified. Authors probably mistook para- infecting fibroblasts in immunologically pro- sitophorous vacuoles containing spores of Un- tected sites. O. diplostomuri intermediate hosts ikaryon, for sporophorous vesicles, characteris- — trematodes Posthodiplostomum minimum tic for species of Pleistophora. and Heterophyes heterophyes parasitizing blue- Pleistophora spp., as a rule, infect fish mus- gills and mullets, respectively, produce long culature (Sanders et al., 2010; Stentiford et al., lasting infections in fish with 100% prevalence 2013). In contrast, representatives of the close- (Lovy, Friend, 2017). Long-term trematode- ly-related genus Ovipleistophora that are mor- fish associations might have helped creating phologically and genetically similar to Pleisto- specialized immunoprotective niches for mi- phora spp., infect oocytes, spermatocytes, and crosporidia. Development of fish-related Pleis- fibroblasts within ovaries and testes of perci- tophora-like microsporidia in the metacercarial form fishes (Summerfelt, Goodwin, 2010). The cyst-wall encapsulation composed of trematode recently described Ovipleistophora diplosto- secretion and fish host fibroblasts, exemplifies muri infects fibroblasts, but only those that form such a niche. fibroblastic capsules around metacercarial cyst More than 20 species of trematode-infecting walls of the diplostomoid trematode Posthod- microsporidia have been placed in the genera iplostomum minimum from internal organs of Nosema and Microsporidium. According to the the bluegill sunfish, Lepomis macrochirus. O. characteristics and host ranges provided by the diplostomuri clusters with trematodes infecting authors, some of those species could be provi- ovaries of perciform fish (Lovy, Friend, 2017). sionally identified as Unikaryon spp. or Pleisto- Tissue tropism similar to that of O. diplostomuri phora spp. None of them has been sequenced, occurred in a microsporidium infecting fibro- and hardly any of them appear to belong to the

Pachygrapsus transversus из Molasses Key, Florida, USA. a — циста зараженной метацеркарии (IC) намного больше чем незараженные метацеркарии (UC). Неокрашенный мазок, световая микроско- пия, дифференциальный контраст по Номарскому; b — зараженные (IC) и незараженные цисты (UC) на полутонких срезах, окрашенных метиленовым синим; c — зараженные метацеркарии в сканиру- ющий электронный микроскоп: паразитофорная вакуоль (PV) заполнена дуплетами спор; d — сдвоенные споры, заключенные в мембрану спорофорного пузырька (стрелка), при большем увели- чении, TEM; e — парзитофорная вакуоль (PV), заполненная спорофорными пузырьками, TEM; f — Unikaryon sp. 2 заражает исключительно секректорные клетки погруженного эпителия тегумента. Стрелка указывает на границы спорофорного пузырька, в который заключены две споры, TEM (мембраны сохранены плохо из-за первичной фиксации параформальдегидом). Hyperparasitic Microsporidia, Haplosporidia, and Myxozoa parasitizing trematodes 107 genus Nosema. We treat those species as an on seems small, including four species by incertae sedis group (see Table 1 for the list and WoRMS and nine species in a recent review associated references). (Azevedo, Hine, 2017). By examining Table 2, A series of experimental studies on viru- one can see there are at least 14 species, includ- lence, host range, and mass production of trem- ing 4 unnamed ones, and probably several more atode-infecting microsporidia was driven by a exist. potential ability of these hyperparasites to bio- Most species of Urosporidium infect trema- logically control the pathogenic trematodes todes, and those that do not still infect worms: Fasciola hepatica and Schistosoma spp. that turbellarian, cestode, nematode, and even a poly- pose a serious threat to human health and cattle chaete (the type species). Seven different fami- breeding worldwide. Suppressing trematode lies of trematodes have been reported as hosts, multiplication at parthenogenetic stages in mol- which indicates a wide range of hosts, especial- luscs by infecting the latter with microsporidia ly when considering the other listed worm hosts served as the major strategy for those experi- (Table 2). Molecular phylogenies show hap- ments. Nosema eurytremae, with its unusually losporidians are cercozoans related to Foramin- wide trematode host specificity, successfully ifera and Radiolaria and probably date back to propagated in lepidopteran larvae under exper- the Cambrian (Azevedo, Hine, 2017). Strict imental conditions (Higby et al., 1979; Pilley et jackknife consensus tree of parsimony analysis al., 1978). Surprisingly, Anncaliia algerae was of SSU rDNA sequence data of two species of selected as the most preferred microsporidian Urosporidium show them to be sister to the species to be used in biological control (Lai, other known haplosporidian genera (Burreson, Canning, 1980). The latter species with dual Ford, 2004), but maximum likelihood trees show natural host specificity in both mosquitoes and it to be nested among species of Haplosporidi- humans has unique generalist properties, allow- um; however, this tree remains unresolved (Aze- ing for experimental infections in a broad range vedo, Hine, 2017). of hosts and cell lines (Sokolova et al., 2019). Microscopy shows species of Urosporidi- Also, using N. strigeoideae against Diplosto- um to have an internal flap of wall material mum spatheceum infecting eye lenses of com- covering the spore orifice as opposed to an mercial and other fishes was explored (Palmieri external hinged lid in those of Haplosporidium et al., 1976). However, all these biological and Minchinia, none of which infects trema- control studies using microsporidia in trema- todes (Azevedo, Hine, 2017). The flask-shaped todes peaked in late 1970’s – early 1980’s spores of most species have one or more exten- (Shigina, 1986), did not have further develop- sions, commonly referred to as tails (Table 2), ment. and their number and length are not consistent; Overall, we conclude that microsporidia of the size of spores does not necessarily present trematodes are drastically understudied even comparable values because some preparations though the complicated trematode polyxenous are fixed, and others are fresh, under intense life cycles probably played an important role in pressure, in sectioned material, or in ultrastruc- dissemination of microsporidia among inverte- tural images. Consequently, values should be brate and vertebrate hosts connected by trophic used as a guide only and not as a taxonomic chains, especially in marine habitats with low character. As the listed and additional species density of inhabitants and limited transmission are examined more critically, including investi- options. gation by molecular techniques, changes in the characteristics of Urosporidium, other haplospo- Haplosporidia ridian genera, and associated nomenclature will All the described Ascetosporea haplospo- be made. For example, a few species of Hap- ridians infecting trematodes belong to the genus losporidium are reported from worms, such as Urosporidium Caullery, Mesnil, 1905. The tax- Haplosporidium malacobdellae in the nemerte- 108 Yu.Ya. Sokolova, R.M. Overstreet . ., 1993 хозяев ., 1973

et al et al других

и

Sprague, 1954; Sprague, Mackin, Loesch, 1968 1954; Menke, Anderson Dollfus, 1941; 1944; Dollfus, 1946 1967 Howell, 1940; Turk, De 1974; Couch, 1978; Overstreet, Overstreet, Shields, 2007 Ormières Caullery, Mesnil, Mesnil, Caullery, 1905 трематод

из

описанные Port to Aransas Texas Galveston, Bay, Moreton Queensland, Australia Indre-et-Loire, Indre-et-Loire, central France both Zealand, New islands East coast and Gulf USA Mexico, of France, Beauduc, Sea Mediterranean English Channel, Channel, English France 5–6 x 6–7 µm, 1 6–7 µm, 5–6 x up to 11 µm tail long 11 to 4.8–5.2 µm, 13 tails ~ 15 µm, 1 tail 16– 1 tail ~ 15 µm, long 20 µm tail single 4–5 µm, long 10–12 µm 1 tail 5–6 µm, 12– 5.5–7.0, 1 tail 14 µm 5 µm, 1 tail up to 1 tail 5 µm, long 15 µm Caullery et Mesnil, 1905,

Caullery et Mesnil, 1905 species described in trematodes and other hosts.

, Urosporidium

Hyper-host Spore size Locality Spore Hyper-host References Donax variablis Donax (Bivalvia) Associated with commercial (Bivalvia)oyster vulgaris Sciurus (Rodentia) (Rodentia) Ostrea lutaria (Bivalvia) Callinectes sapidus Palaemonetes spp. ovata Abra (Bivalvia)

Urosporidium рода

and and Виды

Table 2. 2.

(Syllidae, (Syllidae,

Таблица (Gymnophallidae); (Gymnophallidae); Host Syllis gracilis Syllis sp. (Polyclada) (Polyclada) sp. M. nicolli and Megalophallus and Megalophallus nicolli M. (Microphallidae); sporocysts, sporocysts, (Microphallidae); Life cycle stage; tissue tropism Life cycle stage; tropism tissue . Not in trematode; in coelom of of in coelom Not in trematode; Polychaeta, donacis Parvatrema metacercariae Not in trematode; in tubellarian in tubellarian Not in trematode; Stylochus in cestode Not in trematode, dendritica Catenotaenia longicornutus Bucephalus M. basodactylophallus, Microphallus capitanea, Levinseniella turgidus, possibly sp cercariae, and encysted metacercariae nereicola Gymnophallus unidentified and (Gymnophallidae) sporocysts Monorchiidae; (Bucephalidae); sporocysts and and sporocysts (Bucephalidae); embryonic cercariae Annelida) Annelida) nomen nomen Menke, Menke, Howell, Howell, (type (type

Dollfus, Dollfus, Caullery et et Caullery Anderson, Anderson, De Turk, Turk, De Ormières, Ormières, Parasite Parasite probably

species) nudum Urosporidium Urosporidium fuliginosum 1905 Mesnil, U. astomatµm 1968; cannoni U. U. charletyi constantae U. 1967 U. crescens 1940 U. jiroveci Newman et Lester, Newman 1993 1944 Sprague et Bartoli, 1973 Hyperparasitic Microsporidia, Haplosporidia, and Myxozoa parasitizing trematodes 109 ). ., 1973 ., 2005 ., 1975 ., 2004; et al et al et al ., 2015 et al продолжение et al 2 ( Table 2 (continued). Ormières Ormières Mackin, Loesch, 1954 Perkins Perkins Le Reece 2017 Hine, Azevedo, Caullery, Chapellier Chapellier Caullery, 1943; 1906; Guyénot, 1925, Dollfus, 1970 Sprague, Таблица Beauduc, France, France, Beauduc, Sea Mediterranean Bay, Mobile USA Alabama, Virginia, North Virginia, USA Carolina, Ukraine, Black Sea Sea Black Ukraine, 1963 Dolgikh, Zaika, south and West coasts Korea of New Sydney, South Wales, Australia English Channel, Channel, English France 5.5–7.0 µm, 1 tail 12– 1 tail 5.5–7.0 µm, 14 µm 57 µm 3–5 x 3.8–6.9 x 3.0–5.9 µm 3.0–5.9 µm 3.8–6.9 x 15–17 2–3 tails wide, µm 5.5–7.5 µm, 1 tail 15– 1 tail 5.5–7.5 µm, 45 µm , 3.9–5.5 µm 3.1–4.3 x filaments loop-like AY449714 4–5 µm, 3 tails 3 tails 4–5 µm, Spain NW, Galicia Carballal 4.5–5.5 µm, 1–3 tails 1–3 tails 4.5–5.5 µm, 10–11 µm D. , , (Bivalvia)

) Barnea Barnea (Bivalvia) , Hyper-host Spore size Locality References References size Locality Spore Hyper-host Abra ovata Abra Crassostrea virginica (Bivalvia) Spisula solidissima (Bivalvia) Rissoa splendida splendida Rissoa (Gastropoda Rissoidae edule Cerastoderma (Bivalvia) Ruditapes philippinarum (Bivalvia) Batillaria australis (Gastopoda) Donax trunculus Donax vittatus candida

., 1975 Cercaria ., 1978) et al (Polyclada) et al (Heterophyidae) (Heterophyidae) Bucephalus Bucephalus ( Host Bacciger bacciger

Sulcascaris sulcata sulcata Sulcascaris Paranisakiopsis Paranisakiopsis Perkins ?), ; sporocysts ; sporocysts Life cycle stage, tropism tissue Gymnophallus nereicola Gymnophallus and (Gymnophallidae) Monorchiidae; unidentified sporocysts in juvenile Not in trematode; tentatively nematode ascaridoid as identified by pectinis sporocysts Bucephalidae; but probably (see Lichtenfels Not in trematode; in tubellarian in tubellarian Not in trematode; Paravortex cardii duboisi Parvatrema non-encysted (Gymnophallidae); metacercariae lari Styctodora Bucephalidae redia Hemiuridae; Unidentified (Fellodistomidae) as pectinate haimeanus

sp.

sp. of of sp. sp. Le, sp.

Zaika et

Ormières, Ormières, Perkins, Perkins, Parasite Parasite

Sprague et Bartoli, 1973 Mackin, Loesch, 1954 Díaz, Carballal, 2005 Villalba, Park, Hong, Kang, 2015 Choi, U. jiroveci U. pelseneeri et (Caullery 1906) Chapellier, U. spisuli tauricum U. Urosporidium Urosporidium Urosporidium Urosporidium Zwerner etZwerner Dias, 1975 1963 Dolgikh, Reece, Siddall, Burreson, Stokes, 2004 110 Yu.Ya. Sokolova, R.M. Overstreet

Fig. 4. Pepper spot disease in blue crabs caused by a Urosporidium crescens (Haplosporidia) infection in Microphallus basodactylophallus (Microphallidae). a — life cycle of the digenean M. basodactylophallus. The adult worm in the intestine of the racoon discharges eggs in the host feces which are eaten by and hatch in at least six snail species serving as first intermediate hosts. From the enclosed larva, numerous swimming cercariae are produced asexually. These penetrate the blue crab and encyst as spherical metacercariae. When hyperparasitized by U. cresens, the encysted worm and its cyst wall enlarge to an easily visible size (from about 350 µm to over 650 µm in diameter), with brownish spores giving the heavily infected metacercaria a black appearance. Non hyperparasitized worms develop to adults if eaten by a proper bird or mammal final host (modified from Overstreet, 1978); b — spores from hyperparasitized metacercaria on smear of tissues of the crab with pepper disease. Haplosporidian spores stained red with Giemsa, scale bar — 5 µm; c — cooked crabmeat showing two areas with M. basodactylophallus metacercariae hyperparasitized with U. crescens (“pepper spots”, arrows); d — live spores of U. crescens in the trematode, scale bar — 5 µm. Рис. 4. Болезнь крабов “Pepper spot disease”, вызванная заражением Urosporidium crescens (Haplosporidia) трематоды Microphallus basodactylophallus (Microphallidae). a — жизненный цикл трематоды M. basodactylophallus. Взрослые черви в кишечнике енота откладывают яйца. Последние попадают в фекалии, на которых питается как минимум 6 видов улиток — первых промежуточных хозяев трематоды. Из личинки асексуальным путем формируются многочисленные свободно-плавающие церкарии. Церкарии проникают в краба, инцистируются и преобразуются в сферические метацеркарии. В случае гиперпаразитирования в них U. cresens, инцистированные трематоды увеличиваются в размере (с примерно 350 µm до более чем 650 µm в диаметре) и становятся заметны невооруженным говзом за счет коричневатых спор, которые придают метацеркариям темный цвет. Незараженные черви развиваются во взрослых особей при попадании в желудок окончательного хозяина, птицы или млекопитающнго (по Overstreet, 1978); b — споры из гиперпаразитированных метацеркарий на мазке тканей краба, зараженных “pepper disease”. Споры гаплоспоридий окрашены красным с помощью окрашивания по Гимза-Романовскому, масштаб — 5 µm; c — вареное мясо краба с зонами заражения церкариями M. basodactylophallus с U. crescens (“pepper spots”, стрелки); d — живые споры U. crescens в трематоде, масштаб — 5 µm. an Malacobdella grossa on the pholadid bi- A few species of Urosporidium can influ- valve Zirfaea crispate (see Jennings, Gibson, ence commercial sales of the hyper-hosts such 1968). Urosporidium crescens reported from as the surf clam with infected nematode and blue several hosts and from geographically disparate crab with pepper spot-buckshot (Fig. 4). In both localities may not all be conspecific. The taxo- cases, the spores are brownish but appear black nomic problems should be alleviated once all or to the naked eye. For example, consumers of the most of the species are sequenced. blue crab do not want to eat crabs with disease Hyperparasitic Microsporidia, Haplosporidia, and Myxozoa parasitizing trematodes 111 symptoms, such as the pepper spots. These spots are metacercariae that are packed with cysts and spores of U. crescens, which have caused the metacercariae and cyst wall to en- large several times that of an uninfected meta- cercariae. As it turns out, if the consumer was to eat infected crabs raw, the uninfected metacer- caria could cause a human infection with the trematode, but the hyperinfected metacercaria would not. Pathological responses in cercariae and metacercariae cause mortality of the cercariae and castration of the metacercariae. This seems to be true for all species examined (Azevedo, Hine, 2017).

Myxozoa The first myxosporidian described from a trematode was Fabespora vermicola (Fig. 5) infecting the apocreadiid Crassicutis archosar- gi in Mississippi (Overstreet, 1976b). The in- fection was rare and RMO has not seen it in C. archosargi since. Visual attempts made at the time of original collection to encounter it in the sparid fish host, Archosargus probatocephalus, to determine if both the fish and trematode contained the infection were also unsuccessful. However, in 1980, William Font, who was on sabbatical in RMO’s laboratory, did find what was probably the same species of Fabespora Fig. 5. Fabespora vermicola, the first myxosporidian (Table 3) in the cryptogonimid Metadena cf. species described from trematodes. a — F. vermicola spores (arrows) in the tegument and spectanda in the sciaenid fishes Micropogo- parenchyma of the trematode Crassicutis archosargi nias undulatus and Cynoscion arenareus in (Apocreadiidae) collected from the sheepshead fish, Davis Bayou, Ocean Springs, Mississippi, from Archosargus probatocephalus, scale bar — 20 µm; b — ultrastructure of the F. vermicola sporoblast. Germinative near where infected individuals of A. proba- cell (GEM) with rich glycogen pool (asterisks). CAP cell tocephalus initially occurred (W. Font, R. with mature polar capsules (PC). Note valvular sutures Overstreet, unpublished). The trematode was (arrowheads) separating polar cap (CP) from polar capsule (arrows), scale bar — 1 µm (from Weidner, Overstreet, identified as Metadena spectanda (Overstreet, 1979, with permission form Springer-Verlag). 1971) from M. undulatus and another sciaenid Рис. 5. Fabespora vermicola, первый вид миксос- fish, with the caveat that the species may differ поридий, описанный из трематод. from the larger Brazilian specimens used in the a — споры F. vermicola (стрелки) внутри тегумента трематоды Crassicutis archosargi (Apocreadiidae) из original description. This problem to deter- рыбы Archosargus probatocephalus, масштаб 20 µm; b — mine if all trematode specimens from sciaenids ультраструктура споробласта F. vermicola. Герминаль- in both South and North America are conspe- ная клетка (GEM), богатая гранулами гликогена (звездочки); капсульная клетка со зрелыми полярны- cific can now be solved with DNA sequencing. ми капсулами (PC). Вальвулярные швы указаны Sequencing could also solve the question as to наконечниками стрелок. Видны структуры, разделя- whether all the myxosporidian (Fabespora) ющие полярную шапочку CP от полярной капсулы (стрелки), масштаб 1 µm (по Weidner, Overstreet, 1979, material from Mississippi is conspecific, relat- c разрешения издательства Springer-Verlag). 112 Yu.Ya. Sokolova, R.M. Overstreet . хозяев

групп

., 2009 ., 2004 1981

, et al et al et al. Freeman, Shinn, 2011 Shinn, Freeman, Present study Overstreet, 1976a 1976a Overstreet, Siau Freeman родственных

и

трематод

из

Peninsular Peninsular Malaysia Mississippi, Gulf of Mexico Mississippi, Gulf of Mexico Northwest Spain Aguilar Mediterranean Mediterranean Sea Lake Hamana, Hamana, Lake Japan

описанные , sp. Cynoscion arenareus Cynoscion миксоспоридий Table 3. Myxosporidian species described in trematodes and related hosts.

Megalops cyprinoides cyprinoides Megalops Archosargus Archosargus probatocephalus undulatus Micropogonias and Anguilla anguilla Platycephalus Sparus aurata aurata Sparus Виды 3. as 1

Таблица P. ogawai Allopodocotyle Allopodocotyle (Diplectanidae) (Cryptogonimidae) (Cryptogonimidae) (as

(Apocreadiidae) , probably , probably spectanda spectanda chrysophrii sp. (Ancyrocephalidae) sp. , Opecoelidae) cf. cf. . (2009) by Delane Kritsky (see Kritsky, Nitta, 2019). et al Not in trematode; in monogenean in monogenean in trematode; Not gracilis Diplectanocotyla Metadena Crassicutis archosargi Crassicutis in monogenean in trematode; Not bini Pseudodactylogyrus (Pseudodactylogyridae) in monogenean in trematode; Not Platycephalotrema Sparicotyle Haliotrema chrysophrii

(?)

. sp Siau, of sp. sp. of Freeman, Freeman, of sp.

Parasite Helminth host Hyper-host Locality References References Locality Hyper-host host Parasite Helminth According to figure by Freeman 1 Fabespora vermicola vermicola Fabespora 1976 Overstreet, Fabespora Fabespora 1981 Maillard, Gasc, giardi Myxidium Myxidium incompavermi Shinn, 2011 et Freeman Myxidium Yoshinaga, et Ogawa 2009 Lim, Cépède, 1906 Cépède, Hyperparasitic Microsporidia, Haplosporidia, and Myxozoa parasitizing trematodes 113 ed to another, and related to Fabespora spp. in Other platyhelminths also host myxosporid- fishes. ians (Table 3), such as Myxidium giardi being Another record of infection in a trematode free (not encysted) in the ventral region near the was also identified as Fabespora sp., probably opisthaptor of the monogenean Pseudodactylo- a different species (Siau et al., 1981). It oc- gyrus bini on the branchial tissues from 1 of 323 curred in the opecoelid Sparicotyle chrysophrii examined Anguilla anguilla but in none of the in Sparus aurata from the French Mediterra- related monogenean on the same fish from north- nean Sea (Table 3), and the authors described western Spain (Aguilar et al., 2004). Myxidium ultrastructural aspects of sporogenesis as an incomptavermi was reported from a gill-infest- earlier paper did (Weidner, Overstreet, 1979). ing monogenean (Diplectanocotyla gracilis) on The unusual presence of bundled microfila- Megalops cyprinoides in Malaysia (Freeman, ments (identified as microtubules by Siau et al., Shinn, 2011). It was also detected by PCR in the 1981) in the extracellular space between the kidney, spleen, and intestinal tract of the tarpon valvogenic and interior cells of the sporoblast fish host. Sequences of 1,702 base pairs of SSU attaching to the plasma membranes of both rDNA showed that M. incomptavermi occurred capsulogenic and germinative cells apparently robustly at the base of the multivalvulidan clade allows the spores to propel themselves through (Kudoa, Sphaerospora, and Unicapsula) along- host tissues by undulating their valves (Over- side with another species from Japan (Freeman street, 1976a; Weidner, Overstreet, 1979). Ear- et al., 2009; Table 3). These taxa were placed ly developmental myxozoan stages occurred distantly from the unrelated freshwater and within and around trematode gonads; the ma- marine Myxidium clades. It is important to de- ture disporous spores were enclosed in mem- termine where Fabespora spp. from trematodes brane and passed from the parenchyma to and fit in that tree. All myxosporidian species infect- through the tegument. Heavily infected speci- ing Platyhelminthes cause severe pathological mens had necrotic gonads and a lack or paucity alterations in the worm hosts. of eggs. In M. undulatus infections were found in 1 of 22 worms in the pyloric caeca and in 1 of 6 in the intestines, whereas in C. arenarius in 4 Conclusions of 11 worms in the caeca and in 0 of 15 in the intestine, suggesting infections typically occur Microsporidia in trematodes are common in young individual trematodes (W. Font, R. and are represented by several species. Trema- Overstreet, unpublished). Fabespora spp. also tode-infecting microsporidia with clarified phy- occur in fishes. The type-species, Fabespora logenetic position descend from the species nana, for which DNA has not been sequenced, infecting invertebrates (Unikaryion) and fish infected the Knout goby, Mesogobius batra- (Pleistophora and Ovipleistophora-like spe- chocephalus, in the Black Sea (Naidenova, Zai- cies). However phylogenetic position and ori- ka, 1969) as well as the gall bladder of the cusk- gin of most microsporidia recovered from trem- eel Ophidion rochei but not M. batrachoceph- atodes, remain unknown. alus near Karadag in the Black Sea (Yurakhno, The representatives of only one Haplospo- 2013). Unnamed species occurred in Merluc- ridia genus, Unikaryon, are known to infect cius hubbsi in the Argentine Sea (Cantatore et trematodes, and this genus has a broad host al., 2016) and in Centropomus undecimalis range among marine parasitic and free-living from Tampa Bay, Florida (Landsberg, 1993). marine invertebrates. Landsberg found the spores in the fish host’s All trematode infections with myxoporidia feces and questioned whether they had original- were recovered from fish; they are caused by ly come from a trematode. The relationship species belonging to different clades of Myxo- between fish infections in the Black Sea and zoa, and have switched to trematodes from fish those from trematodes needs to be established. hosts. 114 Yu.Ya. Sokolova, R.M. Overstreet

Parasitic “sporozoans” demonstrate diver- Bojko J., Behringer D.C., Moler P. Reisinger L. 2020. Ovipleistophora diplostomuri, a parasite of fish and sity of characters and physiological mechanisms their trematodes, also infects the crayfish Procam- specific for each group, alongside with common barus bivittatus // J. Invert. Pathol. Vol.169. doi: adaptations in response to similar environmen- 10.1016/j.jip.2019.107306 (Ahead of print). Brumpt E. 1922. Précis de parasitologie. 3rd ed. Paris: tal conditions that have created morphological- Masson et Cie. xv + 1216 p. ly alike forms from genetically dissimilar mate- Burreson E.M., Ford S.E. 2004. A review of recent infor- rial. Indeed, the described above microscopic mation on the Haplosporidia, with special reference to Haplosporidium nelsoni (MSX disease) // Aquat. organisms exemplify an amazing power of con- Living Resour. Vol.17. P.499–517. vergent evolution, the phenomenon that A.A. Canning E.U. 1972. Nosema eurytremae, a replacement Dobrovolskiy and other scholars of the Russian name for the secondary homonym Perezia helmintho- rum Canning and Basch, a parasite of digenean larvae school of parasitology explicitly demonstrated // J. Invertebr. Pathol. Vol.20. P.371. on a variety of parasitic groups (Dogiel, 1962; Canning E.U. 1975. The microsporidian parasites of Platy- Ginecynskaya, Dobrovolskii, 1978). helminthes: their morphology, development, trans- mission and pathogenicity // Commonwealth Institute of Helminthology Miscellaneous Publications No.2. Acknowledgements. We thank Maryanne P.1–32. Anthony, Jean Jovonovich Alvillar, Joyce Shaw, Canning E.U., Barker R.J., Hammond J.C., Nicholas J.P. and Janet Wright for their assistance with refer- 1983. Unikaryon slaptonleyi sp. nov. (Microspora: Unikaryonidae) isolated from echinostome and strigeid ences. This paper was supported in part from a larvae from Lymnaea peregra: observations on its grant by BP Exploration & Production, Inc, and morphology, transmission and pathogenicity // Para- Budgetary Program #0124-2019-0005 at the sitology Vol.87. P.175–184. Canning E.U., Basch P.F. 1968. Perezia helminthorum sp. Institute of Cytology RAS (YS). nov., a microsporidian hyperparasite of trematode larvae from Malaysian snails // Parasitology. Vol.58. The authors declare that there is no conflict P.341–347. of interest regarding the publication of this Canning E.U., Gunn A. 1984. Nosema helminthorum Moniez, 1887 (Microspora, Nosematidae): a taxo- article. The authors are responsible for all data nomic enigma 1 // J. Protozool. Vol.31. P. 525–531. and figures presented in the paper. Canning E.U., Lai P.K., Lie K.J. 1974. Microsporidian parasites of trematode larvae from aquatic snails in West Malaysia // J. Protozool. Vol.21. P.19–25. References Canning E.U., Madhavi R. 1977. Studies on two new species of Microsporidia hyperparasitic in adult Allo- Adl S.M., Simpson A.G., Lane C.E., Lukeš J., Bass D. et creadium fasciatusi (Trematoda, Allocreadiidae) // al. 2012. The revised classification of eukaryotes // J. Parasitology. Vol.75. P.293–300. Eukaryot. Microbiol. Vol.59. P.429–493. Canning E.U., Nicholas J.P. 1974. Light and electron Adl S.M., Bass D., Lane C.E., Lukeš,J., Schoch C.L. et al. microscope observations on Unikaryon legeri (Mi- 2019. Revisions to the classification, nomenclature, crosporida, Nosematidae), a parasite of the metacer- and diversity of eukaryotes // J. Eukaryot. Microbiol. caria of Meigymnophallus minutus in Cardium edule Vol.66. P.4–119. // J. Invert. Pathol. Vol.23. P.92–100. Aguilar A., Aragort W., Álvarez M.F., Leiro J.M., San- Canning E.U., Olson A.C. 1980. Nosema lepocreadii sp. martín M. 2004. Hyperparasitism by Myxidium giardi n., a parasite of Lepocreadium manteri (Digenea: Cépède 1906 (Myxozoa: Myxosporea) in Pseudodac- Lepocreadiidae) from the gut of the California grun- tylogyrus bini (Kikuchi, 1929) Gussev, 1965 (Mono- ion, Leuresthes tenuis // J. Parasitol. Vol.66. P.154– genea: Dactylogyridae), a parasite of the European eel 159. Anguilla anguilla L. // Bul. Eur. Ass. Fish Pathol. Cantatore D.M.P., Irigoitia M.M., Holzer A.S., Timi J.T. Vol.24. P.287–292. 2016. Myxozoans as biological tags for stock identi- Anderson T.J., Newman L.J., Lester R.J.G. 1993. Light fication of the Argentine hake, Merluccius hubbsi and electron microscope study of Urosporidium can- (Gadiformes: Merlucciidae) // Parasitology Vol.143. noni n. sp. haplosporidian parasite of the polyclad P.732–740. turbellarian Stylochus sp. // J. Eukaryot. Microbiol. Carballal M.J., Díaz S., Villalba A. 2005. Urosporidium Vol.40. P.162–168. sp. hyperparasite of the turbellarian Paravortex cardii Azevedo C., Canning E.U. 1987. Ultrastructure of a mi- in the cockle Cerastoderma edule // J. Invertebr. crosporidian hyperparasite, Unikaryon legeri (Mi- Pathol. Vol.90. P.104–107. crosporida), of trematode larvae // J. Parasitol. Vol.73. Caullery M., Mesnil F. 1905. Sur quelques nouvelles P.214–223. Haplosporidies d’Annélides // C. R. Soc. Biol. T.58. Azevedo C., Hine P.M. 2017. Haplosporidia // J. Archiba- P.580–583. ld, A. Simpson, C. Slamovits (eds.). Handbook of the Caullery M., Chappellier A. 1906. Anurosporidium pelse- Protists. Springer, Cham. P.823–850. neeri, n. g. n. sp. haplosporidie infectant les sporo- Hyperparasitic Microsporidia, Haplosporidia, and Myxozoa parasitizing trematodes 115

cysts d’un trématode parasite du Donax trunculus L. vulida // Parasites & Vectors. Vol.4. P.220. // C. R. Soc. Biol, T.60. P.325–328. Freeman M.A., Yoshinaga T., Ogawa K., Lim L.H.S. Colley F.C. 1975. Nosema eurytremae Canning 1972 in 2009. Myxidium-like myxosporean hyperparasites of heart tissue of the land snail Bradybaena similaris // gill monogeneans are basal multivalvulidans // Proc Southeast Asian J. Trop. Med. Public Health. Vol.6. 14th EAFP Meeting, Prague. 273 p. P.142–143. Ginetsinskaya T.A. 1968. [Trematodes, their life cycles, Colley F.C., Joe L.K., Zaman V., Canning E.U. 1975. biology and evolution]. Leningrad: Nauka. 411 p. [In Light and electron microscopical study of Nosema Russian] eurytremae // J. Invertebr. Pathol. Vol.26. P.11–20. Ginetsinskaya T.A., Dobrovolskii A.A. 1978. [Special Couch J.A. 1974. Pathological effects of Urosporidium parasitology. Vol.2. Parasitic worms, Mollusca and (Haplosporida) infection in microphallid metacercar- Arthropoda]. Moscow: Vysshaya Shkola. 292 p. [In iae // J. Invertebr. Pathol. Vol.23. P.389–396. Russian] De Morgan A. 1915. Are Atoms Worlds?: Siphonaptera // Guyénot E. 1943. Sur un Haplosporidie, parasite dans un D.E. Smith (ed.). A Budget of Paradoxes. II (2nd ed.). sporocyste de la Pholade, Barnea candida L. // Rev. P.191. suisse Zool. T.50. P.283–286. De Turk W.E. 1940.The occurrence and development of a Guyénot E., Naville A. 1924. Glugea encyclometrae n. sp. hyperparasite, Urosporidium crescens sp. nov. (Sporo- et G. ghigii n. sp. parasites de platodes et leur dével- zoa, Haplosporidia), which infests the metacercariae oppement dans l’hôte vertébré (“Tropidonotus natrix of Spelotrema nicolli, parasitic in Callinectes sapidus L.”) // Rev. suisse Zool. T.31. P.75–115. // J. Elisha Mitchell Sci. Soc. Vol.56. P.231–232. Guyénot E., Naville A., Ponse K. 1925. Deux microspori- Diamant A., Paperna I. 1985. The development and ultra- dies parasites de trématodes // Rev. suisse Zool. T.31. structure of Nosema ceratomyxae sp. nov., a mi- P.399–421. crosporidian hyperparasite of the myxosporean Cer- Higby G.C., Canning E.U., Pilley B.M., Bush P.J. 1979. atomyxa sp. from Red Sea rabbitfish (Siganidae) // Propagation of Nosema eurytremae (Microsporida: Protistologica. Vol.21. P.249–258. Nosematidae) from trematode larvae, in abnormal Dissanaike A.S. 1957. On Protozoa hyper-parasitic in hel- hosts and in tissue culture // Parasitology. Vol.78. minths, with some observations on Nosema helmintho- P.155–170. rum Moniez, 1887 // J. Helminthol. Vol.31. P.47–64. Howell M. 1967. The trematode, Bucephalis longicornu- Dogiel V.A. 1962. [General Parasitology]. Leningrad: tus (Manter, 1954) in the New Zealand mud-oyster, Leningrad University Press. 464 p. [In Russian] Ostrea lutaria // Trans. Roy. Soc. N. Z., Zool. Vol.8. Dollfus R.P. 1912. Contribution à l’étude des trématodes P.221–237. marins des côtes du Boulonnais: Une métacercaire Hunninen A.V., Wichterman R. 1938. Hyperparasitism: a margaritigène parasite de Donax vittatus da Costa // species of Hexamita (Protozoa, Mastigophora) found Mém. Soc. Zool. France. Vol.25. P.85–144. in the reproductive systems of Deropristis inflata Dollfus R.P. 1925. Liste critique des cercaires marines à (Trematoda) from marine eels // J. Parasitol. Vol.24. queue sétigère signalées jusqu’à present // Trav. Sta. P.95–101. Zool. Wimereux. Vol.9. P.43–65. Hussey K.L. 1971. A Microsporidian hyperparasite of Dollfus R.P. 1941. Titres et travaux scientifiques de Rob- strigeoid trematodes, Nosema strigeoideae sp. n. // J. ert-Ph. Dollfus // In-4 Paris Octobre 1941 Imprimerie Protozoology. Vol.18. P.676–679. Barnéoud–Laval. 76 p. Hussey K.L. 1973. Effects of microsporidian infection on Dollfus R.P. 1944. Hyperparasitisme et castration parasi- larval trematodes: infection with Nosema strigeodeae taire par un sporozoaire chez un Cestode // C. R. Acad. or N. echinostomi // J. Invertebr. Pathol. Vol.22. Sc. T.216. No.11 (1943). P.270–272, fig. 1. P.193–198. Dollfus R.P. 1946. Parasites (animaux et végétaux) des Jennings J.B., Gibson R. 1968. The structure and life Helminthes: Hyperparasites, ennemis et predateurs history of Haplosporidium malacobdellae sp. nov., a des Helminthes parasites et des Helminthes libres // new sporozoan from the entocommensal rhynchoc- Encycl. Biol. 37. Paris: Lechevalier. 481 p. oelan Malacobdella grossa (O.F. Müller) // Arch. Franzen C., Nassonova E.S., Schölmerich J., Issi I.V. Protistenk. Bd.111. P.31–37. 2006. Transfer of the members of the genus Brachiola Kritsky D.C., Nitta M. 2019. Dactylogyrids (Platyhelm- (microsporidia) to the genus Anncaliia based on ultra- inthes: Monogenoidea) infecting the gill lamellae of structural and molecular data // J. Eukaryot. Microbi- Flatheads (Scorpaeniformes: Platycephalidae), with ol. Vol.53. P.26–35. proposal of Platycephalotrema n. gen. and descrip- Freeman M.A., Bell A.S., Sommerville C. 2003. A hyper- tions of new species from Australia and Japan // parasitic microsporidian infecting the salmon louse, Diversity. Vol.11. P.132. doi:10.3390/d11080132. Lepeophtheirus salmonis: an rDNA-based molecular Kudo R. 1924. A Biologic and taxonomic study of the phylogenetic study // J. Fish Dis. Vol. 26. P.667–676. microsporidia // Illinois Biol. Monogr. Vol.9. P.1– Freeman M.A., Sommerville C. 2011. Original observa- 268. tions of Desmozoon lepeophtherii, a microsporidian Kudo R.R. 1939. Observations on Nosema notabilis n. sp. hyperparasite infecting the salmon louse Lepeoph- parasitic in a myxosporidian // Anat. Record (Suppl.). theirus salmonis, and its subsequent detection by Vol.75. P.153. other researchers // Parasites Vectors Vol.4: e231. Lai P.F., Canning E.U. 1980. Infectivity of a microsporid- http:// dx.doi.org/10.1186/1756-3305-4-231. ium of mosquitoes (Nosema algerae) to larval stages Freeman M.A., Shinn A.P. 2011. Myxosporean hyperpar- of Schistosoma mansoni in Biomphalaria glabrata // asites of gill monogeneans are basal to the Multival- Int. J. Parasitol. Vol.10. P.293–301. 116 Yu.Ya. Sokolova, R.M. Overstreet

Landsberg J.H. 1993. Myxosporean parasites of common Nylund S., Nylund A., Watanabe K., Arnesen C.E., Karls- snook in Florida // J. Aquat. Anim. Health. Vol.5. bakk E. 2010. Paranucleospora theridion n. gen., n. P.102–109. sp. (Microsporidia, Enterocytozoonidae) with a life Le T.C., Kang H.-S., Hong H.-K., Park K.-J., Choi K.-S. cycle in the salmon louse (Lepeophtheirus salmonis, 2015. First report of Urosporidium sp., a haplosporid- Copepoda) and Atlantic salmon (Salmo salar) // J. ian hyperparasite infecting digenean trematode Par- Eukaryot. Microbiol. Vol.57. P.95–114. vatrema duboisi in Manila clam, Ruditapes philippi- Ormières R., Sprague V., Bartoli P. 1973. Light and narium on the west coast of Korea // J. Invert. Pathol. electron microscope study of a new species of Urospo- Vol.130. P.141–146. ridium (Haplosporida), hyperparasite of trematode Levron C., Ternengo S., Toguebaye B.S., Marchand B. sporocysts in the clam Abra ovata // J. Invertebr. 2004. Ultrastructural description of the life cycle of Pathol. Vol.21. P.71–86. Nosema diphterostomi sp. n., a microsporidia hyper- Overstreet R.M. 1971. Metadena spectanda Travassos, parasite of Diphterostomum brusinae (Digenea: Zoo- Freitas, and Bührnheim, 1967 (Digenea: Cryptogonim- gonidae), intestinal parasite of Diplodus annularis idae) in estuarine fishes from the Gulf of Mexico // (Pisces: Teleostei) // Acta Protozool. Vol.43. P.329– Proc. Helm. Soc. Wash. Vol.38. P.156–158. 336. Overstreet R.M. 1976a. Fabespora vermicola sp. n., the Levron C., Ternengo S., Toguebaye B.S., Marchand B. first myxosporidan from a platyhelminth // J. Parasi- 2005. Ultrastructural description of the life cycle of tol. Vol.62. P.680–684. Nosema monorchis n. sp.(Microspora, Nosematidae), Overstreet R.M. 1976b. A redescription of Crassicutis hyperparasite of Monorchis parvus (Digenea, Monor- archosargi, a digenean exhibiting an unusual tegu- chiidae), intestinal parasite of Diplodus annularis (Pi- mental attachment // J. Parasitol. Vol.62. P.702–708. sces, Teleostei) // Eur. J. Protistol. Vol.41. P.251–256. Overstreet R.M. 1978. Marine Maladies? Worms, Germs, Lichtenfels J.R., Bier J.W., Madden P.A. 1978. Larval and Other Symbionts from the Northern Gulf of Mex- anisakid (Sulcascaris) nematodes from Atlantic mol- ico // Mississippi-Alabama Sea Grant Consortium, luscs with marine turtles as definitive hosts // Trans. MASGP-78-021. 140 p. Amer. Micros. Soc. Vol.97. P.199–207. Overstreet R.M., Lotz J.M. 2016. Host-symbiont relation- Lie K.J., Basch P.F., Umathevy T. 1966. Studies on Echi- ships: understanding the change from guest to pest // nostomatidae (Trematoda) in Malaya. XII. Antagonism C.J. Hurst (ed.). The Rasputin Effect: when Commen- between two species of echinostome trematodes in the sals and Symbionts Become Parasitic. Advances in same lymnaeid snail // J. Parasitol. Vol.52. P.454–457. Environmental Microbiology Vol.3. P.27–64. Lie K.J., Basch P.F. 1970. Occurrence of Perezia helm- Palmieri J.R., Cali A., Heckmann R.A. 1976. Experimen- inthorum Canning and Basch, 1968 (Microsporida: tal biological control of the eye fluke, Diplostomum Nosematidae) in trematode larvae of fresh-water snails spathaceum, by a protozoan hyperparasite, Nosema // SE Asian J. Trop. Med. Pub. Hlth. Vol.1. P.419–420. strigeoidae (Protozoa: Microsporida) // J. Parasitol. Lovy J., Friend S.E. 2017. Phylogeny and morphology of Vol.62. P.325–326. Ovipleistophora diplostomuri n. sp. (Microsporidia) Palmieri J.R., Lai P.C., Sullivan J.T., Cali A. 1978. Effects with a unique dual-host tropism for bluegill sunfish and of Microsporida on snail and trematode tissue // SE the digenean parasite Posthodiplostomum minimum Asian J. Trop. Med. Pub. Hlth. Vol.9. P.256–259. (Strigeatida) // Parasitology. Vol.144. P.1898–1911. Paperna I., Sabnai I., Castel M. 1978. Microsporidian Lutz A., Splendore A. 1908. Ueber Pebrine und verwandte infection in the cyst wall of trematode metacercariae mikrosporidien. Zweite Mitteilung // Centralbl. Bak- encysted in fish // Ann. Parasitol. Hum. Comp. T.53. teriol. Parasitenkd. Infektionskr. Hyg. Abt.I. Bd.46. P.123–130. S.311–315. Pekkarinen M., Lom J., Nilsen F. 2002. Ovipleistophora Mabbott N.A. 2018. The influence of parasite infections gen. n., a new genus for Pleistophora mirandellae- on host immunity to co-infection with other pathogens like microsporidia // Dis. Aquat. Organ. Vol.48. P.133– // Frontiers in Immunology. Vol.9. P.2579. 142. Mackin J.G., Loesch H. 1954. A haplosporidian hyperpar- Perkins F.O., Zwerner D.E., Dies R.K. 1975. The hyper- asite of oysters // Proc. Natl. Shellf. Assoc. Vol.45. parasite, Urosporidium spisuli sp. n. (Haplosporea), P.182–183. and its effects on the surf clam industry // J. Parasitol. Martin W.E. 1936. A sporozoan parasite of larval trema- Vol.61. P.944–949. todes // J. Parasitol. Vol.22. P.536. Pilley B.M., Canning E.U., Hammond J.C. 1978. The use Menke J.H. 1968. Urosporidium astomatum n. sp., a of a microinjection procedure for large-scale produc- haplosporidian infecting the metacercariae of Par- tion of the microsporidian Nosema eurytremae in vatrema donacis, a trematode parasite of the bivalve Pieris brassicae // J. Invertebr. Pathol. Vol.32. P.355– Donax variabilis. Master’s Thesis. Texas A&M Uni- 358. versity. 40 p. (plus i–ix). Poddubnaya L.G., Tokarev Y.S., Issi I.V. 2006. A new Morris D.J., Freeman M.A. 2010. Hyperparasitism has microsporidium Paratuzetia kupermani gen. et sp. wide-ranging implications for studies on the inverte- n.(Microsporidia), a hyperparasite of the procercoid brate phase of myxosporean (Myxozoa) life cycles // of the cestode Khawia armeniaca Chol. 1915 (Cestoda, Int. J. Parasitol. Vol.40. P.357-369. Caryophyllidea) // Protistology. Vol.4. P.269–277. Naidenova N.N., Zaika W.E. 1969. [Two new species of Reece K.S., Siddall M.E., Stokes N.A., Burreson E.M. Protozoa from the fishes of the Black Sea] // Parazi- 2004. Molecular phylogeny of the Haplosporidia based tologiia (Leningrad). Vol.3. P.97–101 [in Russian, on two independent gene sequences // J. Parasitol. with English summary]. Vol.90. P.1111–1122. Hyperparasitic Microsporidia, Haplosporidia, and Myxozoa parasitizing trematodes 117

Sanders J.L., Lawrence C., Nichols D.K., Brubaker J.F., fishes, Spec. Publ. 5. Washington, D.C.: American Peterson T.S., Murray K.N., Kent M.L. 2010. Pleisto- Fisheries Society. P.511–526. phora hyphessobryconis (Microsporidia) infecting Sprague V. 1977. Annotated list of species of Microspo- zebrafish Danio rerio in research facilities // Dis. ridia // L.A. Bulla Jr., T.C. Cheng (eds.). Comparative Aquat. Organ. Vol.91. P.47–56. Pathobiology. Vol.2, Systematics of the Microsporid- Schäller G. 1959. Microsporidienbefall und Degenera- ia. New York: Plenum Press. P.31–334. tionserscheinungen der Trematodenlarven im Zwis- Stentiford G.D., Feist S.W., Stone D.M., Bateman K.S., chenwirt (Tropidiscus planorbis) // Z. Wiss. Zool. Dunn A.M. 2013. Microsporidia: diverse, dynamic, Bd.162. S.144–190. and emergent pathogens in aquatic systems // Trends Sene A., Ba C.T., Marchan B., Toguebaye B.S. 1997. Parasitol. Vol.29. P.567–578. Ultrastructure of Unikaryon nomimoscolexi n. sp. Stentiford G.D., Ramilo A., Abollo E., Kerr R., Bateman (Microsporida, Unikaryonidae), a parasite of Nomi- K.S., Feist S.W., Bass D., Villalba A. 2017a. Hyper- moscolex sp. (Cestoda, Proteocephalidea) from the spora aquatica n. gn., n. sp. (Microsporidia), hyper- gut of Clarotes laticeps (Pisces, Teleostei, Bagridae) parasitic in Marteilia cochillia (Paramyxida), is closely // Dis. Aquat. Organ. Vol.29. P.35–40. related to crustacean-infecting microspordian taxa // Shields J.D., Overstreet R.M. 2007. Diseases, parasites, Parasitology. Vol.144. P.186–199. and other symbionts. Chapter 8 // V.S. Kennedy, L.E. Stentiford G.D., Ross S., Minardi D., Feist S., Bateman K., Cronin (eds.). The Blue Crab, Callinectes sapidus. Gainey P., Troman C., Bass D. 2017b. Evidence for College Park, Maryland Sea Grant. P.299–417. trophic transfer of Inodosporus octospora and Ovipleis- Shigina N.G. 1986. [Microsporidia species of trematodes, tophora arlo n. sp. (Microsporidia) between crustacean their biology and possible use for biological control] // and ?sh hosts.// Parasitology. Vol.145. P.1105–1117. Protozoologiya. No.10 (Microsporidia). Leningrad: Summerfelt R.C., Goodwin A.E. 2010. Ovipleistophoriasis: Nauka. P.167–182 [in Russian with English summary]. A Microsporidian Disease of the Golden Shiner Ovary / Shigina N.G., Grobov O.F. 1972. [Nosema diplostomi sp. n. / AFS-FHS (American Fisheries Society Fish Health (Microsporidia: Nosematidae), a hyperparasite of trem- Section). FHS blue book: suggested procedures for the atodes of the genus Diplostomum] // Parazitologiya. detection and identification of certain finfish and shell- Vol.6. P.469–475 [in Russian with English summary]. fish pathogens, 2010 edition. American Fisheries Soci- Siau Y., Gasc C., Maillard C. 1981. Premières observa- ety – Fish Health Section, Bethesda, Maryland, USA. tions ultrastructurales d’une myxosporide apparte- Swift J. 1910 (1733). On Poetry: a Rhapsody // E.W. nant au genre Fabespora, parasite de trématode // Browning (ed.). The Poems of Jonathan Swift, D.D., Protistologia. T.17. P.131–137. Volume I. London: G. Bell and Sons, Ltd. Smith R.J. 1959. Ancylid snails: First intermediate host to Toguebaye B.S., Quilichini Y., Diagne P.M., Marchand B. certain trematodes with notes on ancylids as a new 2014. Ultrastructure and development of Nosema host for Megalodiscus and Haematoloechus // Tr. podocotyloidis n. sp. (Microsporidia), a hyperparasite Am. Micr. Soc. Vol.78. P.228–231. of Podocotyloides magnatestis (Trematoda), a para- Sokolova Y.Y., Paskerova G.G., Rotari Y.M., Nassonova site of Parapristipoma octolineatum (Teleostei) // E.S., Smirnov A.V. 2013. Fine structure of Metchni- Parasite. Vol.21. P.44. doi: 10.1051/parasite/2014044. kovella incurvata Caullery and Mesnil 1914 (mi- Vavra J., Undeen A.H. 1970. Nosema algerae n. crosporidia), a hyperparasite of gregarines Polyrhab- sp.(Cnidospora, Microsporida) a pathogen in a labo- dina sp. from the polychaete Pygospio elegans // ratory colony of Anopheles stephensi Liston (Diptera, Parasitology. Vol.140. P.855–867. Culicidae) // J. Protozool. Vol.17. P.240–249. Sokolova Y.Y., Paskerova G.G., Rotari Y.M., Nassonova Voronin V.N. 1974. [On parasitism of microsporidians E.S., Smirnov A.V. 2014. Description of Metchnik- (Microsporida, Nosematidae) in parthogenetic gener- ovella spiralis sp. n. (Microsporidia: Metchnikovel- ations and cercariae of trematodes from freshwater lidae), with notes on the ultrastructure of metchnikov- molluscs] // Parazitologiya (Leningrad). Vol.8. P.359– ellids // Parasitology. Vol.141. P.1108–1122. 364 [in Russian]. Sokolova Y.Y., Overstreet R.M. 2018. A new microspo- Vossbrinck C.R., Debrunner-Vossbrinck B.A., Weiss L.M. ridium, Apotaspora heleios n. g., n. sp. from the 2014. Phylogeny of the Microsporidia // L.M. Weiss, Riverine grass shrimp Palaemonetes paludosus (De- J.J. Becnel (eds.). Microsporidia: pathogens of oppor- capoda: Caridea: Palaemonidae) // J. Invert. Pathol. tunity: First Edition. Wiley-Blackwell. P.203–220. Vol.157. P.125–135. Weidner E., Overstreet R.M. 1979. Sporogenesis of a Sokolova Y., Weidner E., DeMario P. 2020. Development of myxosporidan with motile spores // Cell Tissue Res. Anncaliia algerae (Microsporidia) in Drosophila mela- Vol.201. P.331–342. nogaster // J. Eukaryot. Microbiol. Vol. 67. P.125–131. Yurakhno V.M. 2013. The nature protection aspect of the Sprague V. 1954. Protozoa // P.S. Galtsoff (ed.). Gulf of Black Sea fish myxosporean studies // Vestn. Zool. Mexico – its origin, waters and marine life. U.S. Fish Vol.47. P.62–70. and Wildlife Serv. Fish. Bull. Vol.55. P.243–256. Zaika V.E., Dolgikh A.V. 1963. [A rare case of haplospo- Sprague V. 1964. Nosema dollfusi n. sp. (Microsporidia, ridian hyperparasitism by Urosporidium tauricum sp. Nosematidae), a hyperparasite of Bucephalus cuculus n. in partenites of trematodes of the family Hemiu- in Crassostrea virginica // J. Protozool. Vol.11. P.381– ridae Lühe from the mollusk Rissoa splendida Eichw] 385. // Zool. Zhurn. Vol.42. P.1727–1729 [in Russian, Sprague V. 1970. Some protozoan parasites and hyperpar- with English summary]. asites in marine bivalve mollusks // S.F. Sneiszko (ed.). A Symposium on Diseases of Fishes and Shell- Responsible editor E.N. Temereva