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1.
Bursaphelenchus platzeri n. sp., an associate of nitidulid beetles in southern California, is described and illustrated. Adult males and females of B. platzeri n. sp. were examined by scanning electron microscopy for ultrastructural comparisons with other members of the genus. Bursaphelenchus cocophilus (red ring nematode) appears to be the closest related taxon to B. platzeri n. sp. based upon shared morphological features of the fused spicules, female tail shape, phoresy with non-scolytid beetles, and molecular analysis of the near full-length small subunit (SSU) rDNA. Unfortunately, sequence data from the D2D3 expansion segments of the large subunit (LSU) rDNA and partial mitochondrial DNA COI did not help resolve the relationship of nearest relative. In addition to significant molecular sequence differences in SSU, LSU, and COI, B. platzeri n. sp., which is an obligate fungal feeder, can be differentiated from B. cocophilus because it is an obligate parasite of palms. Bursaphelenchus platzeri n. sp. can be differentiated from all other species of Bursaphelenchus by the length and shape of the female tail and spicule morphology. The spicules are fused along the ventral midline and possess unfused cucullae; the fused unit appears to function as a conduit for sperm. Population growth of B. platzeri n. sp. was measured in a time-course experiment at 25°C in the laboratory on cultures of the fungus Monilinia fructicola grown on 5% glycerol-supplemented potato dextrose agar (GPDA). Nematode population densities rapidly increased from 25 to approximately 200,000/culture within 14 d and then plateaued for up to 28 d.  相似文献   

2.
Gracilacus wuae n. sp. from soil associated with cow parsnip in Ontario, Canada is described and illustrated. Morphologically, females have a long stylet ranging from 80 to 93 µm long, the lip region not offset from the body contour, without lateral lips but with large and flat submedian lobes, the mouth opening slit-like elongated laterally and surrounded by lateral flaps, the excretory pore is anterior to the knobs of the stylet; males without stylet and the pharynx degenerated. The fourth-stage juveniles lack a stylet, the pharynx degenerated, and can be differentiated into preadult females and males based on the position of the genital primordia. The third-stage juveniles are similar to females but smaller. Phylogenetic studies using the rDNA small subunit 18S, large subunit 28S D2/D3, and internal transcribed spacer (ITS) sequences collectively provide evidence of a grouping with other Gracilacus and some species of Paratylenchus with stylet length of females longer than 41 µm deposited in GenBank.  相似文献   

3.
A novel entomopathogenic nematode species, Heterorhabditidoides rugaoensis n. sp. RG081015, collected from Rugao, China, is described. The new species is morphologically very similar to H. chongmingensis but can be distinguished from it on the basis of some morphological characteristics, combined with molecular data and a cross-hybridization test. Males of the new species can be recognized on the basis of body length averaging 1396.2 μm; lateral field with one ridge; metastome isoglottoid with one hemispherical swellings comprised of two to three well-developed warts; asymmetric spicules; peloderan bursa. In IJs, EP = 134.5 μm; ES = 149.3 μm; tail length = 82.5 μm; and a = 20.5. Hermaphroditic females have four to five lateral ridges. The 18S rDNA and ITS sequences of the two nematodes share 99% and 98% identity, respectively. Phylogenetic trees of 18S rDNA and ITS indicate that the new species is most closely related to H. chongmingensis; thus, the two nematodes belong to the same genus. Failure of cross-hybridization between them indicates that nematode strain RG081015 is a novel species and is described herein as H. rugaoensis n. sp. The LC50 of the novel species against Galleria mellonella were 24.35 IJs / ml within 48 hours of infection. Morphological characteristics, genetic similarity analyses, and phylogenetic relationships provide strong evidence that some species of Oscheius/Insectivora-group should be reassigned to the genus Heterorhabditidoides.  相似文献   

4.
Diplogasteroides asiaticus n. sp. is described and illustrated, and its molecular profile and phylogenetic status within the family Diplogastridae are inferred. Morphologically, the new species is characterized by its stomatal structure, a tube-like stoma with three small, rod-like dorsal teeth and two subventral ridges; a spicule clearly ventrally bent at 1/3 from the anterior end; a gubernaculum with a rounded anterior end and sharply pointed distal end in lateral view; nine pairs of genital papillae with an arrangement of <v1, (v2, v3d), C, v4, ad, ph, (v5, v6, v7), pd>; a short tail spike in males; and a well-developed receptaculum seminis, i.e., the antiparallel blind sacs of the uteri beyond the vulva region and elongated conical tail in females. This new species is morphologically similar to D. haslacheri, but it can be distinguished by the morphology of the somewhat shorter tail in females. D. asiaticus n. sp. shares high sequence conservation with D. andrassyi as there is only one base pair difference in the nearly full-length 18S rDNA and seven base pair differences in the D2-D3 expansion segments of the 28S rDNA. Despite this sequence conservation, the species status of D. asiaticus n. sp. was confirmed using the biological species concept, as D. asiaticus n. sp. and D. andrassyi failed to generate viable F2 progeny in hybridization tests.  相似文献   

5.
Four species of Trichodoridae, two of them new and belonging to the T. aequalis complex, are reported from Alaska. Trichodorus carlingi n. sp. differs from all other species of the genus in having conspicuously hamate spicules. Vaginal sclerotizations are trapezoidal to rectangular. Trichodorus paucisetosus n. sp., which resembles T. sparsus Szczygiel, 1968 and T. nanjingensis Liu & Cheng, 1990, has sparsely setose, noncephalated spicules partially striated in one or two zones, oval to round vaginal sclerotizations, sperm in discrete spermathecae, and onchiostyle 57-72 μm long. Trichodorus californicus Alien, 1957 is reported from many sites in Alaska, and T. aequalis Allen, 1957 is reported from one site. Trichodorus californicus was collected almost exclusively from glacial refugial regions north of the Alaska Range.  相似文献   

6.
A new species of entomopathogenic nematode (EPN), Steinernema biddulphi n. sp., was isolated from a maize field in Senekal, Free State Province of South Africa. Morphological and molecular studies indicated the distinctness of S. biddulphi n. sp. from other Steinernema species. Steinernema biddulphi n. sp. is characterized IJs with average body length of 663 μm (606–778 μm), lateral fields with six ridges in mid-body region forming the formula 2,6,2. Excretory pore located anterior to mid-pharynx (D% = 46). Hyaline layer occupies approximately half of tail length. Male spicules slightly to moderately curved, with a sharp tip and golden brown in color. The first generation of males lacking a mucron on the tail tip while the second generation males with a short filamentous mucron. Genital papillae with 11 pairs and one unpaired preanal papilla. The new species is further characterized by sequences of the internal transcribed spacer (ITS) and partial 28S regions (D2-D3) of the ribosomal DNA (rDNA). Phylogenetic data show that S. biddulphi n. sp. belongs to the “bicornutum” clade within the Steinernematidae family.  相似文献   

7.
A root-knot nematode Meloidogyne thailandica n. sp. was discovered on roots of ginger (Zingiber spp.) intercepted from Thailand in October 2002 by the U.S. Department of Agriculture Animal and Plant Health Inspection Service at the port of San Francisco. Comparison by light microscopy (LM) and scanning electron microscopy (SEM) to five other morphologically related species (M. incognita, M. arenaria, M. microcephala, M. megatyla, and M. enterolobii) revealed that the new species differs from these by one or more of the following: body, tail and hyaline tail length, shape of head, tail and tail terminus of second-stage juveniles; stylet length and shape of spicules in males; perineal pattern, stylet length and shape of knobs in females. The distinctive perineal pattern is oval to rectangular, with smooth to moderately wavy and coarse striae, and with characteristic radial structures present underneath the pattern area; the dorsal arch is high, sometimes round to rectangular, and striae in and around the anal area form a thick network-like pattern interrupted by lateral lines and large phasmids. Second-stage juveniles have a long, slender tail and long, gradually tapering hyaline tail region ending in a rounded terminus. Male spicules commonly have an acutely angled shaft with a bidentate terminus. Molecular data from the ribosomal large subunit D3 expansion segment revealed four haplotypes, two of which were unique and distinguish M. thailandica n. sp. from M. arenaria, M. incognita, and M. javanica.  相似文献   

8.
Parasitodiplogaster comprises a potentially large radiation of nematode species that appear to be parasitically bound to their Agaonid fig wasp hosts, which are mutualistically associated in the syconia (figs) of the diverse plant genus Ficus. Parasitodiplogaster laevigata n. sp. is described and illustrated as an associate of the fig wasp, Pegoscapus sp. from Ficus laevigata from southern Florida. It is the first species of Parasitodiplogaster reported from North America and is closest to P. trigonema from F. trigonata from Panama. Parasitodiplogaster laevigata n. sp. can be differentiated from all described species of Parasitodiplogaster based on stomatal morphology (presence of a large dorsal and a right subventral tooth) in the adults of both sexes, molecular comparisons of two expansion segments (D2,D3) of the large subunit (LSU) rRNAgene, and fig-fig wasp host affinities. The ultrastructure of P. laevigata n. sp. was elucidated using TEM and SEM for comparisons with other species of Parasitodiplogaster. The stoma of P. laevigata n. sp. possesses a nonsegmented cheilostomal ring that connects to the longitudinal body musculature per- and interradially, a claw-like dorsal tooth, a right subventral tooth, and telostegostomatal apodemes arising from the dorsal side of each subventral sector. The unification of the pro-, meso-, and metastegostom with the gymnostom in P. laevigata n. sp. and further simplification in other described species may be due to derived adaptations associated with the internal parasitism of fig wasps.  相似文献   

9.
Steinernema scapterisci n. sp., isolated in Uruguay from the mole cricket Scapteriscus vicinus, can be distinguished from other members in the genus by the presence of prominent cheilorhabdions, an elliptically shaped structure associated with the excretory duct, and a double-flapped epitygma in the first-generation female. The spicules of the male are pointed, tapering smoothly to a small terminus, and the shaft (calomus) is long, bearing a sheath. The gubernaculum has a long, upward-bent anterior part. The ratio of head to excretory pore divided by tail length of the third-stage juvenile is greater for S. scapterisci n. sp. than for S. carpocapsae. Steinernema scapterisci n. sp. did not hybridize with S. carpocapsae strain Breton. In laboratory tests, S. scapterisci n. sp. killed 10% or less of non-orthopteran insects, including the wax moth larva, a universal host for other species of Steinernema.  相似文献   

10.
The free-living marine nematodes Leptosomatides brevicaudatus n. sp. and L. marinae were described and redescribed, respectively, from material collected in the northwest Pacific. Leptosomatides brevicaudatus n. sp. from Simushir Island differs from L. marinae in the ratio c8 (body length divided by tail length measured on the chord) and the length of the spicules. Leptosomatides marinae is redescribed from light microscopy (LM) observations of the type specimens and LM and scanning electron microscopy (SEM) observations of specimens from Hokkaido, Japan. It appears to be impossible to distinguish among some species of Leptosomatides because they are either insufficiently described or known only from females. Secondary sexual characters of males are essential for purposes of identification.  相似文献   

11.
Rhabditis (Oscheius) pheropsophi n. sp., associated with cadavers of the bombardier beetle, Pheropsophus aequinoctialis, is described from material collected in Brazil. Mean body length of the female is 1,217 μm, of the male 872 μm, and of the dauer juvenile 568 μm. The female has six lips with one papilla on each lateral lip and two on each sublateral lip; stoma wall thickened dorsally, metarhabdions with warts, excretory pore near base of esophagus, tail long (c = 8), and phasmids prominent, protruding on scanning electron microscope preparations. The male has 10 pairs of bursal ribs, with the terminal pair considerably smaller than the others; spicules fused distally two-thirds of their length. The new species can be distinguished from other members of the Dolichura-group by its fused spicules.  相似文献   

12.
Leptonchoid species found in soil samples taken in lowland and mid-elevation seasonal forests at four locations in Panama were as follows: Sclerostylus karri n. gen., n. sp., Basirotyleptus saccatus n. sp., B. nemoralis, B. acus, B. penetrans, Doryllium neotropicum n. sp., D. minor, Tyleptus gymnochilus, Gerthus jamesi, Dorylaimoides micoletzkyi, and Tylencholaimellus macrophallus. The discoveries corroborate our earlier suggestion of a Gondwanian origin for Tyleptus and Basirotyleptus and provide data for additional biogeographical study.  相似文献   

13.
Strelkovimermis spiculatus n. sp. (Mermithidae: Nematoda), a parasite of the mosquito Aedes albifasciatus Mac. in Argentina, is described. Diagnostic characters of this species include a ventrally shifted mouth opening and spicules fused at the tips. The mermithid has been reared on Culex pipiens L. larvae in the laboratory.  相似文献   

14.
Funaria maryanneae n. sp., distinguished by its large size and long prerectum, is described from specimens collected in Bad Sooden, Germany, D. B. R. This nematode was collected also from Fräkmüntegg (Mt. Pilatus), Switzerland. Proleptonchus weischeri n. sp., with short hemispheroid female tail and relatively anterior vulva, is described from specimens collected in Kaufunger Wald near Kassel, Germany, D. B. R. This is the first report of either genus from the continent of Europe. Leptonchus parisii Zullini, 1973, from Chiapas, Mexico, becomes a junior synonym of Funaria obtusa (Thorne, 1939) Goseco, Ferris and Ferris, 1974. Leptonchus acutus Zulliui, 1973 becomes Funaria acuta n. comb., and Funaria rothi Goseco, Ferris and Ferris, 1974 becomes a junior synonym of Funaria acuta.  相似文献   

15.
Chitwoodius brasiliensis n.sp. is described from soil around plant roots in Vicosa, MG State, Brazil. It has a body 1.9 mm (1.6-2.5) long, odontostyle and odontophore 33 μm (31-37) and 34 μm (31-36) long, respectively, and males with spicules 59-61 μm long. Chitwoodius rusticulus n.sp. from Colombian rain forest differs from other species of the genus in having a weakly muscular anterior part of the oesophagus, a pore-like vulva, and an unsclerotized vagina. Vanderlindia venata n.sp. from lucerne soil in South Kilimanjaro, Tanzania, differs from the type and only other known species of its genus in having a smaller and less slender body (L = 3.34 mm [3.15-3.71], a = 50 [46-53]), odontostyle 2.3-2.5 times lip region width long, and stylet guiding ring located at 1.2-1.4 times lip region width from anterior end.  相似文献   

16.
Two new gregarines in the recently erected genus Psychodiella (formerly Ascogregarina), Psychodiella sergenti n. sp. and Psychodiella tobbi n. sp., are described based on morphology and life cycle observations conducted on larvae and adults of their natural hosts, the sand flies Phlebotomus sergenti and Phlebotomus tobbi, respectively. The phylogenetic analyses inferred from small subunit ribosomal DNA (SSU rDNA) sequences indicate the monophyly of newly described species with Psychodiella chagasi. Ps. sergenti n. sp. and Ps. tobbi n. sp. significantly differ from each other in the life cycle and in the size of life stages. The sexual development of Ps. sergenti n. sp. (syzygy, formation of gametocysts and oocysts) takes place exclusively in blood-fed Ph. sergenti females, while the sexual development of Ps. tobbi n. sp. takes place also in males and unfed females of Ph. tobbi. The susceptibility of Phlebotomus perniciosus, Phlebotomus papatasi, Ph. sergenti, Ph. tobbi, and Phlebotomus arabicus to both gregarines was examined by exposing 1st instar larvae to parasite oocysts. High host specificity was observed, as both gregarines were able to fully develop and complete regularly the life cycle only in their natural hosts. Both gregarines are considered as serious pathogens in laboratory-reared colonies of Old World sand flies.  相似文献   

17.
Panagrellus ceylonensis n. sp. is described from rubber latex in Ceylon. Its long, slender spicules are curved ventrally with a dorsal deflection at two-thirds of their length. The manubrium is thick and hooked, and the shaft is not widened at the shoulder. The terminal bifurcations are wide, with the dorsal one considerably longer and thicker than the ventral. The main ventral element is continuous with the terminal sheath with the ventral bifurcation arising within it.  相似文献   

18.
Meloidogyne chitwoodi n. sp. is described and illustrated from potato (Solanum tuberosum) originally collected from Quincy, Washington, USA. This new species resembles M. hapla, but its perineal pattern is basically round to oval with distinctive and broken, curled, or twisted striae around and above the anal area. The vulva is in a sunken area devoid of striae. Vesicles or vesicle-like structures are present in the median bulb of females. The larva tail, being short and blunt with a hyaline tail terminal having little or no taper to its rounded terminus, is distinctively different from M. hapla. SEM observations revealed the nature of the perineal pattern and details of the head of larvae and males, and showed the spicules to have dentate tips ventrally. Hosts for M. chitwoodi n. sp. include potato, tomato, corn, and wheat but not strawberry, pepper, or peanut. The latter three crops are excellent hosts for M. hapla. The known distribntion of this new root-knot species presently involves certain areas of Idaho, Washington, and Oregon. The common name "Columbia root-knot nematode" is proposed for M. chitwoodi n. sp.  相似文献   

19.
The present study describes the molecular phylogenetic analysis of Dactylogyroides longicirrus (Monogenea: Dactylogyridae) infecting the gill filaments of fish Puntius sophore from the site Guwahati, Assam, India. The parasite Dactylogyroides longicirrus (Tripathi, 1959) Gusev, 1976 from Northeast Indian region is presented based on sequence data of a 738 base-pair fragment of ribosomal 18S small subunit and first internal transcribed spacer (ITS 1). Phylogenetic relationships were inferred using neighbour joning and maximum parsimony methods and the results support the validation of D. longicirrus. The study is also supported by secondary structure model prediction by using minimum free energy which can be considered a promising tool for monogenean species identification. This is the first report of this parasite from Northeast region of India, with this, the 18S and ITS 1 rDNA region amplified in the study is also the first sequence of the genus Dactylogyroides.  相似文献   

20.
Noctuidonema dibolia n. sp., an ectoparasite of adults of the noctuid moth Mocis latipes (Guenée) is described. The differentiating characters are a club-shaped body with a subterminal vulva in the female, spicules with a reduced matrix and sheath and closely apposed dorsal and ventral arms in the male, very long stylet and conus, moderately prominent stylet knobs, a bluntly rounded head, and a large renette cell in both sexes. Lateral fields, rectum, anus, bursa, and gubernaculum are absent. Noctuidonema dibolia differs from the other species of the subfamily Noctuidonematinae in the size and robustness of the body, the length of the stylet and conus, the length of the tail, and the shape of the spicules.  相似文献   

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