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Metaparasitylenchus hypothenemi is an endoparasitic nematode that causes partial or total sterility of coffee berry borer (Hypothenemus hampei) females, although the causes are unknown. Fecundity a...

Se cita y describe por primera vez para ArgentinaParasitylenchus pseusobifurcatus sp.n. (Tylenchida, Allantonematidae), parásito de adultos deHarmonia axyridis(Pallas, 1773) (Coleopera, Coccinellidae). Esta nueva especie está muy cercana a P. bifurcatus Poinar Jr. y Steenberg, 2012, por la característica de tener todas las hembras vermiformes y los machos inmaduros la punta del apéndice caudal bifurcada, pero se diferencian entre otros por el tamaño del gubernáculo. Se describe su fórmula cariotípica. Publicación registrada en Zoobank:LSIDurn:lsid:zoobank.org:pub:751C7C95-EDD7-4D3F-80FA-0BBC5339E404 Acto nomenclatural:LSIDurn:lsid:zoobank.org:act:31912097-A9DF-47C5-9294-2E9DEA879AED, Parasitylenchus pseusobifurcatus sp.n. ( Tylenchida, Allantonematidae) is described for the first time for Argentina as a parasite of adults of Harmonia axyridis (Pallas, 1773) (Coleopera, Coccinellidae). The new species is closed to P. bifurcatus Poinar Jr. & Steenberg, 2012, by the characteristic of having the tail tip of all vermiform females and immature males bifurcated, but they differ by the size of the gubernaculum. Its karyotype formula is described. Publicación registrada en Zoobank:LSIDurn:lsid:zoobank.org:pub:751C7C95-EDD7-4D3F-80FA-0BBC5339E404 Acto nomenclatural:LSIDurn:lsid:zoobank.org:act:31912097-A9DF-47C5-9294-2E9DEA879AED

We assessed the parasitism of Metaparasitylenchus hypothenemi on its host, the coffee berry borer, in 20 coffee plantations of Mexico. A total of 23,568 adult borers were dissected, with 179 of the...

For the frst time in Argentina, we report that in Harmonia axyridis Pallas, 1773, and Cycloneda sanguinea (Linnaeus, 1763) (Coleoptera, Coccinellidae) parasitizing by nematodes which belong to the family of Allantonematidae (Nematoda, Tylenchida). The genera are Metaparasitylenchus Wachek, 1955 (Nickle, 1967), Sulphuretylenchus Rühm, 1956 (Nickle, 1967) and Contortylenchus Rühm, 1956. They will be described and photographied afterwards., Se cita por primera vez para la Argentina nemátodos parásitos de Harmonia axyridis Pallas, 1773, y Cycloneda sanguinea (Linnaeus, 1763) (Coleoptera, Coccinellidae), estos nemátodos pertenecen a la familia de Allantonematidae (Nematoda, Tylenchida). Los géneros hallados son Metaparasitylenchus Wachek, 1955 (Nickle, 1967), Sulphuretylenchus Rühm, 1956 (Nickle, 1967) y Contortylenchus Rühm, 1956. Se describen y fotografían., Centro de Estudios Parasitológicos y de Vectores

Originally published on the Featured Creatures Website at http://entnemdept.ufl.edu/creatures/nematode/Thripinema_spp.htm Includes: Introduction - Distribution - Life Cycle and Biology - Symptoms - Hosts and Identification - Economic Importance - Management - Selected References

Background It is rare to find terrestrial nematode lineages parasitizing arthropods inhabiting the intertidal or littoral zone of the oceans. During an ecological study along the Oregon dunes, an allantonematid nematode (Tylenchomorpha: Allantonematidae) was discovered parasitizing the intertidal shore bug, Saldula laticollis (Reuter)(Hemiptera: Saldidae). This shore bug is adapted to an intertidal environment and can survive short periods of submergence during high tides. The present study describes the nematode parasite and discusses aspects of its development, ecology and evolution. Methods Adults and last instar nymphs of S. laticollis (Hemiptera: Saldidae) were collected from the high intertidal zone among clumps of Juncus L. (Juncaceae) plants at Waldport, Oregon on October 3, 2011. The bugs were dissected in 1% saline solution and the nematodes killed in 1% Ringers solution and immediately fixed in 5% formalin (at 20°C). Third stage juveniles removed from infected hosts were maintained in 1% saline solution until they matured to the adult stage, molted and mated. Results Halophilanema prolata n. gen., n. sp. (Nematoda: Allantonematidae) is described from last instar nymphs and adults of the intertidal bug, Saldula laticollis on the Oregon coast. The new genus can be distinguished from other genera in the Allantonematidae by a stylet lacking basal knobs in both sexes, an excretory pore located behind the nerve ring, ribbed spicules, a gubernaculum, the absence of a bursa and the elongate-tubular shape of the ovoviviparous parasitic females. Studies of the organogenesis of Halophilanema showed development to third stage juveniles in the uterus of parasitic females. Maturation to the free-living adults and mating occurred in the environment. The incidence of infection of S. laticollis ranged from 0% to 85% depending on the microhabitat in the intertidal zone. Conclusions Based on the habitat and morphological characters, it is proposed that Halophilanema adapted a parasitic existence fairly recently, evolutionarily speaking. It was probably a free-living intertidal or shore nematode that fed on microorganisms, especially fungi, in the intertidal habitat and became parasitic after saldids entered the environment. Halophilanema represents the first described nematode parasite of an intertidal insect.

Ants can serve as developmental, definitive, intermediate, or carrier hosts of a variety of nematodes. Parasitic ant nematodes include members of the families Mermithidae, Tetradonematidae, Allantonematidae, Seuratidae, Physalopteridae, Steinernematidae, and Heterorhabditidae. Those nematodes that are phoretically associated with ants, internally or externally, are represented by the Rhabditidae, Diplogastridae, and Panagrolaimidae. Fossils of mermithids, tetradonematids, allantonematids, and diplogastrids associated with ants show the evolutionary history of these relationships, some of which date back to the Eocene (40 mya).

Adults of the invasive harlequin ladybird, Harmonia axyridis (Coleoptera: Coccinellidae), were found to be parasitized by nematodes (Tylenchomorpha: Allantonematidae) in Denmark. The nematodes were identified as Parasitylenchus sp. Major morphological characters of the nematodes did not differ significantly from Parasitylenchus coccinellinae Iperti & van Waerebeke 1968, but minor deviations in egg dimension and tail length were measured. Parasitism was only recorded in early autumn, with prevalence ranging from 2 to 33%. Adult and juvenile nematodes occurred together in the body cavity of both female and male H. axyridis.

This research note reports a nematode, preliminarily identified as belonging to the genus Thripinema Siddiqi (Allantonematidae), parasitizing females of the endemic New Zealand flower thrips Thrips obscuratus (Crawford) (Thysanoptera: Thripidae) in New Zealand. Nematodes were observed in the abdomen of infested thrips throughout the year and were associated with thrips sterilization.

Adults of the invasive harlequin ladybird, Harmonia axyridis (Coleoptera: Coccinellidae), were found to be parasitized by nematodes (Tylenchomorpha: Allantonematidae) in Denmark. The nematodes were identified as Parasitylenchus sp. Major morpho- logical characters of the nematodes did not differ significantly from Parasitylenchus coccinellinae Iperti & van Waerebeke 1968, but minor deviations in egg dimension and tail length were measured. Parasitism was only recorded in early autumn, with prevalence ranging from 2 to 33%. Adult and juvenile nematodes occurred together in the body cavity of both female and male H. axyridis.

Background The harlequin ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae) is native to central and eastern Asia and was purposely introduced into Europe to control aphids. While it proved to be a good biological control agent, its rapid spread and buildup of large populations made it a nuisance, since it overwinters in homes, emits unpleasant odors, stains fabrics, occasionally bites humans and feeds on apples, pears and grapes. Aside from the above, the ravenous appetite of H. axyridis results in their consumption of harmless native insects, including even other ladybird beetles. A study of the natural enemies of H. axyridis in Denmark revealed the presence of nematodes. The present study describes this nematode parasite and discusses aspects of its development and ecology. Methods Adult harlequin ladybird beetles were collected from March to November from four localities in Copenhagen on different plant species. In addition, groups of last-instar larvae and pupae (n = 50) were examined for the presence of nematodes. Living and recently dead nematodes were removed from adult H. axyridis in 0.5% saline solution, the nematodes were then heat killed (at 75C), fixed in 5% formalin and transferred to glycerin on slides for further examination and measurements. Results A new species of Allantonematidae (Tylenchida), Parasitylenchus bifurcatus n. sp., is described from adults of the harlequin ladybird, Harmonia axyridis in Denmark. The new species is characterized by a straight stylet lacking basal thickenings, a bursa and a forked tail tip in the vermiform (infective) females and juvenile males. The new species is compared with P. coccinellinae previously described from ladybird beetles in France. Parasitism resulted in depletion of the fat body and partial or complete atrophy of the reproductive organs of the beetles. Infections occurred throughout the year with rates of parasitism reaching up to 35%. The rate increased to 60% when field-collected ladybirds were incubated for 30 days in the laboratory. Conclusions The production of subsequent generations within the host with only the fertilized females (not the males) leaving the hosts and the absence of parasitism of the larvae and pupae is an impressive developmental modification of P. bifurcatus. It is proposed that the vermiform (infective) females pass from one adult host to another when the beetles are hibernating or in assemblage groups. Rates of parasitism show that P. bifurcatus could be a significant biological control agent of H. axyridis.

Incurvinema helicoides n. gen., n. sp. (Nematodea, Tylenchida : Allantonematidae) parasite du Siphonaptere Rhadinopsylla pentacantha (Rothschild, 1897) infeode aux Arvicolidae est decrit a partir de puces de nids de Talpa europaea. Le cycle, la specificite et l’impact sur l’hote sont presentes et discutes. Le nouveau genre se separe facilement de Psyllotylenchus par les femelles gamogenetiques parasites a courbure ventrale et les femelles parthenogenetiques dont la glande preuterale, de petite taille, n’est pas spherique.

Spilotylenchus arthuri gen. n., sp. n. (Nematodea, Tylenchida : Allantonematidae) parasite du Siphonaptere Spilopsyllus cuniculi (Dale, 1878) infeode au lapin de garenne, est decrit a partir d’un materiel provenant de la region parisienne et comprenant des femelles parasites et des adultes, mâles et femelles, libres. Neoparasitylenchus megabothridis Laumond et Beaucournu, 1977 et N. laplandicus Rubtzov et Darskaya, 1981, sont consideres comme appartenant a ce nouveau genre. S. arthuri provoque un blocage de l’oogenese chez les puces femelles.

Megaselia halterata (Wood) (Diptera: Phoridae), parasitized by an endoparasitic nematode, Howardula husseyi Richardson, Hesling, Riding (Tylenchida: Allantonematidae), were reared at temperatures of 13, 16, 18, 21, 24, and 27°C. Rearing temperature of 27°C produced a nematode-free phorid culture. Mushroom crops were infested with nematode-free female phorid populations of 1,900, 3,110, 9,800, 12,443, and 12,766 per m2 of growing surface during spawn run. Populations greater than 12,000 phorid females significantly reduced mushroom yield. Two generations of phorids were observed during the cropping period.

Face flies, Musca autumnalis (Diptera: Muscidae), of both sexes infected with the nematode, Heterotylenchus autumnalis (Tylenchida: Allantonematidae), visited the faces of cattle and fresh cattle dung. However, female flies greatly outnumbered males at both sources. Generally. infected male flies found on cattle and dung contained young nematodes. In contrast, infected females on cattle contained nematodes of all ages, and most infected females from dung contained older nematodes. The propensity of healthy female flies to visit faces of cattle and dung depended on their gonadotrophic age. The majority of flies with immature eggs were found on cattle while the majority with mature eggs were found on dung. Infected flies containing early nematode stages appeared to behave like healthy ones with immature eggs. However, once the nematodes invaded the flies' ovaries, the flies' behavior changed. These infected flies were found primarily on dung and apparently became “terminal” dung feeders.

SUMMARY The longevity of male and female Megaselia haltherata, 75% of parasitised by the nematode Howardula husseyi, was studied for 16 days at 20- 21.5 OC. A statistical model fitted to the data indicated that parasitism reduced fly longevity significantly; predicted times to 50% mortality were about 6 days shorter for parasitised males, but only 2 days shorter for parasitised females. An investigation of the number of nematode larvae liberated by female flies at intervals throughout the experiment showed that many had been liberated in the first 4 days, and that the rate of release then gradually declined. A statistical model for nematode dissemination rate was used to estimate the mean number of nematodes released at 4-day intervals by surviving flies containing 1–5 adult H. husseyi. Mass release of laboratory-reared parasitised flies on mushroom farms has been suggested as a possible method of boosting the incidence of parasitism in farm fly populations. The results of the present study indicate that if such a measure were taken in spawn-running rooms then the best effect might be attained by releasing the flies in two batches with one release occurring in the middle of each week of the spawn-run.

Howardula colaspidis, a nematode parasite of the grape colaspis (Colaspis brunnea) is described. This species closely resembles H. dominicki but can be distinguished from the latter by having fewer ovarian cells, a longer uterus, and a shorter vulva to tail tip distance in the infective female. Also, the parasitic female of H. colaspidis is longer and relatively narrower than that of H. dominicki. Juveniles exited from female beetles during oviposition and occasionally from beetle larvae, but not from parasitized male beetles. Parasitism did not appear to reduce the fecundity of the adult. Over a 2-year period, parasitism of the host insect declined from 24 to 3% in corn and soybean fields in northeastern North Carolina.

L’ evolution des capsules induites par la presence de Contortylenchus diplogaster dans le tissu adipeux d’Ips sexdentatus est suivie par une etude histologique depuis la nymphose du Scolyte jusqu’a sa ponte.Au debut du stade nymphal de l’insecte, la femelle parasite de C. diplogaster n’a pas encore pondu et les noyaux de la capsule qui l’entoure sont groupes par tetrades ; certains presentent un etat de degenerescence avancee. Ces observations suggerent que la capsule syncytiale resulterait, en plus de fusions cellulaires, d’une multiplication amitotique des noyaux, suivie d’une degenerescence de certains d’entre eux. A la fin du stade nymphal, les noyaux, separes les uns des autres, sont repartis a la peripherie de la capsule. La ponte du nematode a lieu quand l’hote est adulte. Apres developpement des larves a l’interieur de la capsule, celle-ci finit par se rompre en general apres que le scolyte ait attaque un nouvel arbre-hote. Les larves quittent alors l’insecte et se repandent dans les galeries.Le developpement parasitaire de C. diplogaster s’effectue toujours en totalite dans le tissu adipeux du Scolyte.

Sphaerularia bombi Duf. is recorded for the first time as a parasite of bumblebee queens in Canada. The nematode was collected from the abdominal cavity of queens of Bombus terricola Kby. and B. ternarius Say from Saskatoon, Saskatchewan.Sphaerularia hastata, sp. nov., is described from the mountain pine beetle, Dendroctonns monticolae Hopk., the Douglas-fir beetle, D. pseudotsugae Hopk., and the cocoon of a hymenopterous parasite, Coeloides dendroctoni Cush., from Steamboat Mountain, British Columbia.

A new species of nematode, Sphaerularia ungulacauda (Allantonematidae), is described from the Douglas fir beetle, Dendroctonus pseudotsugae Hopk, from British Columbia, Canada. The diagnostic characters of the genus Sphaerularia are emended and a key to species is given.

Nematode parasites of the family Allantonematiclae were found in the body cavity of male and female Polygenis tripus . This is the first time such parasites have been recorded in South American fleas and in a representative of the family Rhopalopsyllidae. P. tripus commonly occurs on wild rodents in Brazil and is a potential vector of bubonic plague in certain parts of the country.

Les auteurs decrivent une nouvelle espece de Nematode entomogene : Psyllotylenchus chabaudi n. sp. (Tylenchida : Allantonematidae) parasite de Nosopsyllus fasciatus (Bosc) (Siphonaptera : Ceratophyllidae) , puce du rat, accidentellement presente sur Oryctolagus cuniculus. La nouvelle espece d' Allantonematidae presente en particulier une volumineuse glande preuterale. Une comparaison des especes du genre Psyllotylenchus actuellement considerees comme valides est donnee dans la diagnose.

1. Two species of Allantonematidae were found parasitizing five of twelve species of Drosophila collected at Rothamsted Experimental Station, Harpenden, Herts, England.2. H. aoronymphium sp.nov. was found in 20·8 % of D. phalerata and 4·3 % of D. kuntzei examined. Parasitylenchus diplogenus sp.nov. was found in about 5 % of D. subobscura, D. obscura, and D. silvestris examined.3. The type species and taxonomy of the genus Parasitylenchus are discussed.4. The life history of H. aoronymphium is typical of most allantonematids except that the female is fertilized when she is a fourth-stage larva. P. diplogenus has two sexual generations per cycle.5. Both nematodes have a precocious development of the male and a retarded development of the female genital system. Both destroy host gonads.6. The specificity of the nematodes is not a result of dissimilar ovipositing habits of the hosts, but shows a similarity to the taxonomic assignment of the hosts to subgenera.

ADULTS of Drosophila spp. trapped at frequent intervals in Nature at Dalkeith, Midlothian, were dissected to follow the development of the ovaries, and occasionally the testes, during autumn, winter and spring. The flies dissected were D. subobscura Coll. (19 males, 338 females), D. obscura Fin. (17 males, 92 females), D. silvestris Bas. (41 males, 34 females), D. tristis Fln. (2 males, 7 females), D. funebris (Fabr.) (3 males, 11 females), and D. cameraria Hal. (3 females). During these dissections a few specimens of the first three species were observed to be infested with a nematode, provisionally identified as Aphelenchulus sp. (Allantonematidae Chtw. and Chtw., 1937), probably new. The numbers of dissected flies are shown in Table 1, the figures in parentheses being the numbers of those infested.

Psyllotylenchus vivriparus , n. gen., n. sp. (Nematodea: Tylenchida: Allantonematidae) parasitizes the fleas Catallagia sculleni rutherfordi Augustson, Monopsyllus wagneri (Baker), Monopsyllus ciliatus protinus (Jordan) and Diamanus montanus (Baker) in California. Psyllotylenchus has an alternation of gamogenetic and parthenogenetic parasitic cycles similar to Heterotylenchus , but differs from that genus in possessing ovoviviparous gamogenetic females which curve with the ventral surface outward when relaxed with gentle heat. Parthenogenetic females also possess a distinct spherical preuteral gland, Heterotylenchus pawlowskyi Kurochkin, 1960 is transferred to the genus Psyllotylenchus .