Microsporidian infection of a marine nematode, Metoncholaimus scissus

1970 ◽  
Vol 16 (3) ◽  
pp. 371-377 ◽  
Author(s):  
B.E. Hopper ◽  
S.P. Meyers ◽  
R. Cefalu
2012 ◽  
Vol 11 (12) ◽  
pp. 1544-1551 ◽  
Author(s):  
A. M. Ardila-Garcia ◽  
N. M. Fast

ABSTRACT Microsporidia are unicellular fungi that are obligate endoparasites. Although nematodes are one of the most abundant and diverse animal groups, the only confirmed report of microsporidian infection was that of the “nematode killer” ( Nematocida parisii ). N. parisii was isolated from a wild Caenorhabditis sp. and causes an acute and lethal intestinal infection in a lab strain of Caenorhabditis elegans . We set out to characterize a microsporidian infection in a wild nematode to determine whether the infection pattern of N. parisii in the lab is typical of microsporidian infections in nematodes. We describe a novel microsporidian species named Sporanauta perivermis (marine spore of roundworms) and characterize its infection in its natural host, the free-living marine nematode Odontophora rectangula. S. perivermis is not closely related to N. parisii and differs strikingly in all aspects of infection. Examination by transmission electron microscopy (TEM) revealed that the infection was localized in the hypodermal and muscle tissues only and did not involve the intestines. Fluorescent in situ hybridization (FISH) confirmed infection in the muscle and hypodermis, and surprisingly, it also revealed that the parasite infects O. rectangula eggs, suggesting a vertical mode of transmission. Our observations highlight the importance of studying parasites in their natural hosts and indicate that not all nematode-infecting microsporidia are “nematode killers”; instead, microsporidiosis can be more versatile and chronic in the wild.


Zootaxa ◽  
2019 ◽  
Vol 4695 (2) ◽  
pp. 195-200
Author(s):  
JING SUN ◽  
HONGXIU ZHAI ◽  
YONG HUANG

A new free-living marine nematode species from marine sediments in the East China Sea, is described here as Perspiria boucheri sp. nov. The new species is characterized by amphideal fovea surrounded partially by body annulations; four cephalic setae stout; conical buccal cavity with a minute dorsal tooth and two ventrosublateral teeth; pharynx with a pyriform terminal bulb; tail elongated, conical with 3/4 posterior cylindrical portion which having distinct coarse annulations; spicules strongly curved with narrow ventral velum, handle-shaped proximally; gubernaculum canoe-shaped, without apophysis. The new species differs from the most similar species Perspiria striaticaudata (Timm, 1962) by strongly curved spicules with handle-shaped proximal end, gubernaculum without dorsal apophysis and relatively shorter tail. Updated key to all species of Perspiria is provided. 


Oceanography ◽  
2018 ◽  
Vol 31 (4) ◽  
pp. 113-121
Author(s):  
Catalina Pastor de Ward ◽  
Virginia Lo Russo ◽  
Martin Varisco

Nematology ◽  
2021 ◽  
pp. 1-11
Author(s):  
Daisuke Shimada ◽  
Toshiki Komiya ◽  
Toyoshi Yoshiga

Summary A new species of free-living marine nematode, Diplolaimella ariakensis n. sp., is described from a muddy tidal flat of the Ariake Sea, southern Japan. Diplolaimella ariakensis n. sp. differs from its congeners by the following: presence of ocelli, absence of denticles in the buccal cavity, a long tail (11-14 cloacal body diam., c = 3.2-4.0 in male, 17-21 anal body diam., c = 2.9-3.4 in female), spicules as long as 1.4-1.8 cloacal body diam., gubernaculum 0.4-0.5 cloacal body diam. long with a dorsocaudal apophysis 0.5-0.7 cloacal body diam. long, presence of a precloacal supplement, absence of postcloacal papillae, presence of seven pairs of body pores in male, and the anterior position of the vulva (V = 43-46). A dichotomous key to Diplolaimella species is provided. Almost full-length 18S rRNA and partial cytochrome c oxidase subunit I gene sequences were determined for D. ariakensis n. sp. A maximum likelihood tree of 18S sequences supported a close relationship between D. ariakensis n. sp. and D. dievengatensis.


2008 ◽  
Vol 51 (4) ◽  
Author(s):  
Aung Swe ◽  
Rajesh Jeewon ◽  
Stephen B. Pointing ◽  
Kevin D. Hyde

Development ◽  
1998 ◽  
Vol 125 (1) ◽  
pp. 143-150
Author(s):  
D.A. Voronov ◽  
Y.V. Panchin

Early cleavages of the marine nematode Enoplus brevis are symmetrical and occur in synchrony. At the 2- to 16-cell stages, blastomeres are indistinguishable. The progeny of blastomeres was investigated by intracellular injections of fluorescent dyes and horse radish peroxidase. One blastomere of the 2-cell embryo gives rise to a compact group of cells occupying about half of an embryo. The border between labeled and unlabeled cells differs in each embryo dividing it to anterior-posterior, left-right or intermediate parts. At the 8-cell stage, one blastomere gives rise to only endoderm, whereas the other blastomeres produce progeny that form multiple cell types, including nerve, muscle and hypoderm cells, in various proportions. Thus the fates of the blastomeres of early E. brevis embryos, with the exception of the endoderm precursor, are not determined. The process of gastrulation in E. brevis is very similar to that in Caenorhabditis elegans and other nematodes. At the beginning of gastrulation, the 2-celled endoderm precursor lies on the surface of embryo and then sinks inwards. After labeling of cells on the ventral side (near endoderm precursor) at the beginning of gastrulation, their progeny differentiate predominantly into body muscles or pharyngeal cells of the first stage larva. Cells that are located more laterally give rise mainly to neurons. The dorsal blastomeres differentiated principally into hypoderm cells. Our study suggests that a precise cell lineage is not a necessary attribute of nematode development.


Sign in / Sign up

Export Citation Format

Share Document