Phylogeny of Myxobolidae (Myxozoa) and the evolution of myxospore appendages in the Myxobolus clade

Genera Myxobolus Bütschli, 1882 and Henneguya Thélohan, 1892 (Myxobolidae) are specious myxozoan genera. They comprise nearly half of overall known myxozoan species diversity. A typical spore feature of Henneguya is the presence of two caudal appendages of the spore valves, which distinguishes them from species of the genus Myxobolus. Several Myxobolus spp., however, were reported to show aberrant spores with Henneguya-like caudal appendages. We found such aberrant spores in Myxobolus tsangwuensis and Myxobolus wulii. We studied the ultrastructure of M. wulii and Myxobolus oralis spores with caudal appendages by transmission electron microscopy (TEM). TEM of these aberrant spores revealed that their caudal appendages have the same ultrastructure as the appendages of Henneguya spp. Small caudal appendages of M. wulii spores observed only on TEM suggested that this character may be often overlooked and more Myxobolus species potentially have the ability to express the caudal appendages on the myxospore. In order to trace the evolution of this character, we performed broad phylogenetic analysis of all species of the family Myxobolidae which are available in GenBank including nearly 300 taxa. We found at least eight independent evolutionary origins of spores with two appendages, three origins of a single appendage and 12 apparent secondary losses of the spore projections. Therefore, genus Henneguya with typical two-tailed myxospores is polyphyletic, however a majority of its species has a common ancestor and groups in the second largest subclade of the Myxobolus clade. We also mapped the biological characteristics (host, site of infection and environment) of Myxobolidae species on the phylogenetic tree. We revealed an evident host-associated evolutionary pattern in all parts of the Myxobolus clade with a distinct and species-rich subclade containing almost exclusively species infecting species of the Order Cypriniformes.     

Eimeria clethrionomyis sp. n., Eimeria gallatii sp. n., Eimeria pileata sp. n. and Eimeria marconii sp. n. from the Red-Backed Vole Clethrionomys gapperi Vigors,from Pennsylvania§

SYNOPSIS Four new eimerian species are described from red-backed voles. Clethrionomys gapperi in Pennsylvania. Sporulated oocysts of Eimeria clethrionomyis sp. n. are ellipsoidal, 18.8 (16.5–21.5) × 14.9 (14.0–16.5) with elongate, ovoid sporocysts, 10.6 (9.5–12.0) × 6.1 (5.5–7.0). The oocyst wall is smooth, with 2 layers, and thins, with terminal cap at one or both ends. Polar granules, dark Stieda body and sporocyst residuum are present. The occyst residuum is absent. Sporulated oocysts of Eimeria gallatii sp. n. are ellipsoidal, 27.7 (21–32) × 19.3 (17–24) with ovoid sporocysts, 13.5 (12–15) × 8.8 (8–10). The oocyst wall is smooth, 2-layered, with a micropyle and thin wall at the end opposite the micropyle. Polar granules. Stieda body and sporocyst residuum are present. The oocyst residuum is atypical, of cobwebby material. Sporulated oocysts of Eimeria pileata sp. n. are subspherical to spherical, 25.2 (20.5–29.5) × 22.5(19.5–25.5) with ellipsoidal sporocysts, 13.4(10.5–15.0) × 8.4 (7.5–9.5). The oocyst wall is rough, pitted, striated, 2-layered, with no micropyle. Polar granules, oocyst and sporocyst residuum. Stieda body and stiedal cap are present. Sporulated oocysts of Eimeria marconii sp. n. are ellipsoidal, 13.0 (10.5–15.0) × 10.6 (9.5–12.0) with elongate, ovoid sporocysts, 7.7 (7.0–8.5) × 4.2 (3.0–4.5). The oocyst wall is smooth, single-layered, with no micropyle. Polar granules, dark Stieda body and sporocyst residuum are present. There is no oocyst residuum.     

Ciliate Protozoa in the Rumen of Brazilian Water Buffalo,Bubalus bubalis Linnaeus*

SYNOPSIS Total numbers and distribution of genera, subgenera and species were determined for the ciliate protozoa in rumen contents of 4 Brazilian water buffalo Bubalus bubalis Linnaeus. The fauna of one animal, housed in close proximity to European and zebu-type cattle, differed considerably from that of the remaining animals, which were somewhat isolated on a large ranch. Several of the protozoan species observed in the semi-isolated animals were first described in rumen contents from humped Indian cattle, and their subsequent occurrence in other hosts and geographic locations has been limited or absent. In all, 49 different species of protozoa were found, 8 of which have not been previously described. Three of the new species belong to the genus Entodinium: E. ciculum sp. n., E. spinonucleatum sp. n. and E. triangulum sp. n.: 4 to Diplodinium (Ostracodinium): D. (O.) brazili sp. n., D. (O.) esalqum sp. n., D. (O.) nucleolobum sp. n., and D. (O.) tiete sp. n.; and one to Diplodinium (Eudiplodinium): D. (E.) bubalus sp. n.     

Two new species of Myxobolus (Myxozoa: Myxobolidae) infecting the gill and scales of the smallmouth bass,Micropterus dolomieu (Centrarchiformes: Centrarchidae) in the French Broad River Basin,North Carolina

Two new species of Myxobolus Bütschli, 1882 (Bivalvulida: Myxobolidae) are described from the gill and scales of smallmouth bass (Micropterus dolomieu Lacepède, 1802 [Centrarchiformes: Centrarchidae]) from the Watauga River, French Broad River Basin, North Carolina, United States. Myxobolus intralamina n. sp. infects the lumen of the lamellar arterioles and Myxobolus infrabractea n. sp. infects the inner surface of the scale. They differ from all congeners by a combination of myxospore dimensions, polar tubule coil count, and the presence or absence of an iodinophilic vacuole in the sporoplasm and an intercapsular process. A phylogenetic analysis of the small subunit ribosomal DNA (SSU rDNA) recovered M. intralamina n. sp. sister to Myxobolus lepomis and Myxobolus branchiarum and M. infrabractea n. sp. sister to Myxobolus micropterii in a clade composed of five Myxobolus spp. infecting centrarchids and Henneguya spp. (Myxobolidae) infecting percids. Histological sections of infected gill revealed intra-lamellar plasmodia of M. intralamina n. sp. within the lumen of the lamellar arterioles and plasmodia of M. infrabractea n. sp. developing beneath the scales. These new species comprise the first species of Myxobolus reported from a black bass (Micropterus Lacepède, 1802) in the Southeast United States.     

A skin disease of the eels caused by Myxobolus kotlami n. sp.

In elvers (Anguilla anguilla) imported yearly to a fish farm in Hungary the regular occurrence of a Myxobolus infection was recorded. The parasite produces oval or spherical plasmodia of 0.1–0.2·0.07–0.12mm in the subcutaneous and intermuscular connective tissue of the head. In each piasmodium about 200 to 400 spores develop which differ morphologically from the spores of all Myxobolus species known from the eel and other fishes. Based upon the characteristic location of plasmodia and spore morphology, this parasite is described as a new species, Myxobolus kotlani.     

Fine Structure and Life Cycle of Lankesteria clarki sp. n. (Sporozoa: Eugregarinida) Parasitic in the Mosquito Aedes sierrensis (Ludlow)

Lankesteria clarki sp. n. from the treehole mosquito, Aedes sierrensis (Ludlow) in California, is described. This species can be separated from the closely related ones, L. culicis (Ross) and L. barretti Vávra, by the totally intracellular nature of the trophozoite, the shape of the gamont, the position of the gamont nucleus and the structure and position of the residual body in the spore. Morphologic and ultrastructural investigations of gametogenesis and sporogony were conducted and the host relationship discussed. Lankesteria clarki was found in mosquitoes collected from all treeholes examined near Novato in Marin County, California and an examination of over 6,000 larvae of A. sierrensis showed an infection rate of 27.5%. The parasite is capable of destroying the midgut epithelial cells during its trophic stage and Malpighian tubule cells during gametogenesis and sporogony.     

Two New Species of Myxozoa, Myxobolus inaequus sp. n. and Henneguya theca sp. n. from the Brain of a South American Knife Fish, Eigemannia virescens (V.)

Two new species of Myxozoa from the brain of the green knife fish Eigemannia virescens are described: Myxobolus inaequus sp. n. has an unusually large spore body and extremely unequal polar capsules, and Henneguya theca sp. n. has an attenuated spore encased in a sheath not previously described in other Myxozoa. Only spores of the two species were observed, and infections caused no obvious pathological changes in the brain.     

Henneguya tunisiensis n. sp. (Myxosporea: Bivalvulida), a new gill parasite of Symphodus tinca (L.) (Teleostei: Labridae) off Tunisia

Henneguya tunisiensis n. sp., a new myxosporean, is described from the gill-arches of the East Atlantic peacock wrasse Symphodus tinca (L.) collected from off the Kerkennah Islands, Tunisia. It is characterised by the presence of elongate white plasmodia of 1–1.5 × 1.5–2 mm in size. The mature spores are rounded in frontal view and have two identical polar capsules and two caudal appendages which taper considerably at the end. Both light and electron microscopical data show that this species differs in several morphological features from all previously described Henneguya spp. A molecular analysis, based on 18S rDNA sequence data, indicates that H. tunisiensis n. sp. is readily distinguishable from other myxozoan DNA sequences in GenBank. Phylogenetically, the new species is placed in the marine Henneguya clade, which is a sister group of marine Myxobolus spp. from perciform fishes in Tunisian waters.     

Haemogregarina pseudemydis n. sp. (Apicomplexa: Haemogregarinidae) and Pirhemocyton chelonarum n. sp. in Turtles from Louisiana*

SYNOPSIS. The blood of each of 95 turtles (8 species) collected from southeastern Louisiana was infected with some or all of the merogonic stages and gametocyte stage of Haemogregarina pseudemydis n. sp. Five species of turtles harbored Pirhemocyton chelonarum n. sp. Turtle Haemogregarina and Pirhemocyton are locality records for Louisiana. Pirhemocyton is reported for the first time in turtles and in the continental U.S.A.     

Seven New Eimeria spp. (Protozoa,Coccidia) from Freshwater Fishes of Canada*

Seven new species of Eimeria are described and figured from the freshwater fishes of Ontario and Quebec, Canada. They are Eimeria catostomi sp. n. and E. fernandoae sp. n. from Catostomus commersoni (Lacépède), E. etheostomae sp. n. from Etheostoma exile (Girard), E. hoffmani sp. n. from Umbra limi (Kirtland), E. micropteri sp. n. from Micropterus dolomieui Lacépède E. pungitii sp. n. from Pungitius pungitius (Linnaeus), and E. salvelini sp. n. from Salvelinus fontinalis (Mitchill). Furthermore, 2 new host records and 2 new distribution records for North America are reported for E. anguillae Léger & Hollande, 1922 and E. truttae Léger & Hesse, 1919 respectively. Finally, morphologically similar oocysts found in various cyprinids are regarded as belonging to E. iroquoina Molnar & Fernando, 1974.     

Morphological conservatism in the foreleg structure of cicada hatchlings,Burmacicada protera n. gen., n. sp. in Burmese amber,Dominicicada youngi n. gen., n. sp. in Dominican amber and the extant Magicicada septendecim (L.) (Hemiptera: Cicadidae)

Two cicada hatchlings (Hemiptera: Cicadidae) in Burmese and Dominican amber are described as Burmacicada protera n. gen., n. sp. and Dominicicada youngi n. gen., n. sp., respectively. Although very similar in appearance, the two species can be separated by body contour, the nature of the process on the terminal antennomere and the shape and size of protrusions, teeth and spines on the forelegs. A comparison of the forelegs of the fossil hatchlings with those of an extant hatchling of the periodical cicada, Magicicada septendecim (L.), reveals a remarkable degree of morphological conservatism over 100 million years. A brief review of fossil cicadas is presented.     

Systematics of the Eimerian Parasites from North American Snakes of the Family Colubridae,and their Prevalence in the Colubrids of Iowa*

A survey of 117 Iowa snakes, representing 18 species within 12 genera, revealed the presence of 6 species of Eimeria, 5 of which are described as new and 1 of which (E. zamenis) is redescribed. Those species found, the average length-width dimensions of their oocysts ( in micrometers ), and the respective hosts from which they were isolated were as follows: E. attenuata sp. n., 22.2 × 12.6, from 1 of 25 red-sided garter snakes [Thamnophis sirtalis parietalis (Say)] and 1 of 14 northern water snakes [Natrix sipedon sipedon (Linnaeus)]; E. iowaensis sp. n., 17.8 × 14.5, from 1 of 25 redsided garter snakes; E. hydrophis sp. n., 15.4 × 10.9, from 5 of 14 northern water snakes and 1 of 1 diamond-backed water snake [N. rhombifera rhombifera (Hallowell)]; E. helmisophis sp. n., 13.8 × 10.6, from 1 of 5 western worm snakes [Carphophis amoenus vermis (Kennicott)]; E. collanuli sp. n., 33.1 × 18.3, from 1 of 14 prairie ring-neck snakes (Diadophis punctatus arnyi Kennicott), and E. zamenis, 31.0 × 17.0, from 1 of 6 eastern yellow-bellied racers (Coluber constrictor flaviventris Say) and 1 of 1 eastern milk snake [Lampropeltis triangulum triangulum (Lacépède)]. The overall infection rate for the 117 snakes examined was 9.2%; these data are tabulated. In addition, the possible synonymy of E. lampropeltis with E. zamenis is considered, and the probable status of E. attenuata, E. hydrophis, E. zamenis, and E. annea, as parasites of multiple host species, is reviewed with regard to the phylogenetic relationships of the respective hosts from which they have been reported.     

Growth of Crithidia at High Temperature: Crithidia hutneri sp. n. and Crithidia luciliae thermophila s. sp. n.*

SYNOPSIS. Crithidia hutneri sp. n. and Crithidia luciliae thermophila s. sp. n. are described. Both flagellates can be grown in a defined medium over a temperature range of 15–37°C. The requirements for amino acids, vitamins, purine and hemin, and pH range were similar to those established for Crithidia fasciculata, although threonine was required as a growth factor for C. luciliae thermophila at high temperatures. Adenosine could be used by the 2 Crithidia as a purine source at 28 but not at 37 C.     

The Status of Knowledge of the Genus Ecdyonurus in the Iberian Peninsula,with Description of Two New Species of the E. venosus Group from Spain (Ephemeroptera: Heptageniidae)

As a result of studies of material of Ecdyonurus from Spain, nymphs and adults of two new species, E. baeticus sp. n. and E. olgae sp. n., are described. Three species described by Navás must be considered as nomina dubia (E. diversus Navás, 1923, E. excelsus Navás, 1927 and E. fluminum var. speciosus Navás, 1915). Variability in adults of E. venosus is figured and discussed.     

Four New Species of Eimeria and One of Tyzzeria from the Ceylon Jungle Fowl Gallus lafayettei*

One species of Tyzzeria and 4 new species of Eimeria are described from the Ceylon jungle fowl Gallus lafayettei. The sporulated oocysts of Tyzzeria galli sp. n. are 13.8 (12–15) μ m; of Eimeria lafayettei sp. n., 19.5 (19–21) X 14.2 (13.5–15) μ m; of Eimeria indentata sp. n., 30.3 (29.5–32) X 21.4 (20–22) μ m; of Eimeria symmetrica sp. n., 35 × 28.5 μ m, and of Eimeria dissanaikei sp. n., 21 (19–23) X 14 (12–16) μ m. E. indentata, E. symmetrica, and E. dissanaikei produced patent infections in domestic fowl but T. galli and E. lafayettei did not. This is the 1st record of the genus Tyzzeria from the order Galliformes.     

<Emphasis Type="Italic">Pleuroxus</Emphasis>-like chydorids (Crustacea: Anomopoda) from South Africa,with the description of <Emphasis Type="Italic">Dumontiellus africanus</Emphasis> gen. n., sp. n.

Five species of Pleuroxus-like chydorids are found in new material from South Africa or are known from the literature. One species is here described as Dumontiellus africanus gen. n., sp. n., endemic to South Africa. Handling editor: K. Martens     

Rumen Ciliate Fauna of Alaskan Moose (Alces americana), Musk-Ox (Ovibos moschatus) and Dall Mountain Sheep (Ovis dalli)*

Total numbers, generic distribution and percentage species distribution were determined for the ciliate protozoa in rumen contents obtained from Alaskan moose (Alces americana), musk-ox (Ovibos moschatus) and Dall mountain sheep (Ovis dalli). The musk-ox has a fauna somewhat similar to that previously observed in reindeer and caribou. In contrast, only protozoa in the genus Entodinium were observed in moose, while Dall mountain sheep have a fauna unique among Alaskan ruminants studied to date. Other than Entodinium exiguum which was common to all animals, only 2 additional species of Entodinium, observed in the moose and musk-ox, occurred in more than one animal species. Four new species of protozoa are described, Entodinium dalli sp.n., Entodinium constrictum sp.n. and Polyplastron alaskum sp.n. from the Dall mountain sheep and Entodinium alces sp.n. from moose.     

Coccidian Parasites from Iowa Turtles: Systematics and Prevalence*

SYNOPSIS. A survey of 22 Western Painted Turtles (WPT), Chrysemys picta belli Gray; 2 Map Turtles (MT), Graptemys geographica Le Sueur; 8 False Map Turtles (FMT), Graptemys pseudogeographica Gray; 26 Illinois Mud Turtles (IMT), Kinosternon flavescens spooneri Smith; and 5 Spiny Softshell Turtles (SST), Trionyx spiniferus Le Sueur, revealed the presence of 10 species of coccidia. The species found, the shape and average length-width dimensions (in micrometers) of their oocysts, and the respective hosts from which they were isolated were as follows: Eimeria chrysemydis Deeds & Jahn, slightly pear-shaped (27.6 × 17.0), from 5 WPTs; Eimeria delagei marginata Deeds & Jahn, markedly pearshaped (22.1 × 17.6), from 2 WPTs, 1 MT, and 3 FMTs; Eimeria graptemydos sp. n., broadly ellipsoid to subspherical (12.6 × 11.4), from 10 WPTs, 2 MTs, and 5 FMTs; Eimeria lutotestudinis sp. n., broadly ellipsoid to subspherical (11.9 × 10.8), from 4 IMTs; Eimeria mascoutini sp. n., broadly ellipsoid to subspherical with outer surface of oocyst wall mammillated (14.0 × 11.9), from 2 SSTs; Eimeria mitraria (Laveran & Mesnil), asymmetrically ellipsoid, bearing 1 or 2 conical projections at the polar end and 2 or 3 at the antipolar end (10.0 × 7.6), from 7 WPTs, 1 MT, 3 FMTs, and 4 IMTs; Eimeria pseudogeographica sp. n., narrowly ellipsoid to slightly ovoid (19.5 × 13.5), from 5 WPTs and 3 FMTs; Eimeria tetradacrutata sp. n., spherical to subspherical with outer surface of oocyst wall mammillated (19.5 × 19.2), from 1 WPT; an Eimeria sp. narrowly ellipsoid, bearing 2 conical projections at the polar end and 2 at the antipolar end (23.8 × 13.2), from 1 MT; and Mantonella hammondi sp. n., conical to narrowly ellipsoid, bearing 1 conical projection at the polar end and 2 or 3 at the antipolar end (14.3 × 7.1), from 1 IMT. The overall infection rate for the 63 turtles examined was 54.0%.