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1.
Aphelenchoides microstylus n. sp. and Seinura onondagensis n. sp., a nematode predator, are described from dead Scots pine (Pinus sylvestris L.) in Onondaga County, New York. Females of A. microstylus are 370 to 485 µm long. The body is slender and tapers posteriorly to an amucronate, pointed terminus. The head is continuous with the body, and lips bear a stylet guide. Diagnostic characters of females are three incisures in the lateral field, a short stylet (6-7.5 µm) with small basal knobs, a single row of oocytes, and a long postuterine sac (25-50 µm). Males are characterized by small spicules (10-11µm); two pairs of post-anal, subventral papillae; and a single row of spermatocytes. A bursa and gubernaculum are absent. Seinura onondagensis females are characterized by a body of moderate length (475-595 µm), finely annulated cuticle, and a slightly set-off head. Diagnostic characters are four incisures in the lateral field, long stylet without basal knobs (17-22 µm), single row of oocytes, and presence of a postuterine sac (14-38 µm). Males are unknown. The monospecific genus Indaphelenchus is proposed as a synonym of Seinura, and S. siddiqii n. comb. is proposed for the only species, I. siddiqii.  相似文献   

2.
A new species of the genus Nothacrobeles is described from natural areas (a salt lake) in the Southeast Iberian Peninsula. Nothacrobeles lanceolatus sp. n. is characterized by its body length, two rows of cuticular punctations per annulus, labial probolae bifurcate with divergent prongs, pharyngeal corpus 2.4 to 3.5 times isthmus length, spermatheca length, postuterine sac 0.5 to 1.1 times the corresponding body diameter ratio, female tail conical and bearing a spindle-shaped or conical mucro with acute terminus, phasmid at 8 to 17 µm posterior to the anus, male tail conical with acute mucro, spicules length, and gubernaculum length. In addition, Nothacrobeles cf. lunensis and Zeldia punctata are studied. Cervidellus capricornis is transferred to genus Nothacrobeles. A key to species of Nothacrobeles is also provided.  相似文献   

3.
Three new species of Rhabdochona Railliet, 1916 are described and illustrated from Salmo gairdneri Richardson (rainbow trout) in freshwater streams in California: Rhabdochona californiemis n. sp., R. paxmani n. sp., and R. satmonis n. sp. Rhabdochona californiensis n. sp. is characterized by 14 anteriorly directed teeth in the prostome, egg devoid of filaments or floats, male and female tail terminus with a single mucro, left (long) spicule slender with a moderate distended podoid terminal end, spicular ratio 1:3.8. Rhabdochona paxmani n. sp. is characterized by 10 teeth in the prostome, eggs with polar floats, left (long) spicule slender with podoid terminus distended and having a minute subterminal spine; right spicule with prominent gorgeret (barb), spicular ratio 1:4.3, male and female tail terminus with a cuticular conical rounded short projection. Rhabdochona salmoni, n. sp. is characterized by 10 teeth anteriorly directed in the prostome, eggs with polar floats, left spicule slender with a distended podoid terminus; right spicule with a sharply indented gorgeret, spicular ratio 1:4.3, male and female tail terminus with a conical or rounded tip.  相似文献   

4.
Divisispiculimermis mirus n. gen., n. sp., a mermithid parasitizing larvae of Chironomus sp. in the Cajón o Grande Stream, Córdoba, Argentina, is described. The new genus differs from all other mermithid genera in having paired spicules which are separated and divided into proximal and distal sectors. The other diagnostic characters of the genus are medium size, nematodes with the cuticle appearing smooth (lacking cross fibers under the light microscope); head separated from the rest of the body by a slight constriction at the level of the amphids, six cephalic papillae, mouth papillae absent, mouth opening posterior to level of cephalic papillae; six hypodermal chords at midbody; weakly S-shaped vagina; postparasitic juvenile with a tail appendage.  相似文献   

5.
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   

6.
Distribution of caudal papillae in adult Romanomermis culicivorax was determined by scanning electron microscopy. Ninety eight caudal papillae, each containing one pore, were present in males but absent in females. Papillae were arranged in three longitudinal rows, one ventral, two ventrolateral; the middle ventral row bifurcated anterior to the spicule. The appearance of the papillae was different anterior and posterior to the spicule. The role of the caudal papillae in mediating copulatory behavior was discussed.  相似文献   

7.
8.
Nematode parasites and associates of four bark beetle species in British Columbia were surveyed. Bursaphelenchus varicauda n.sp., Ektaphelenchus macrostylus, Panagrolaimus dentatus, and Cryptaphelenchus latus were found associated with Dendroctonus pseudotsugae. Parasitorhabditis obtusa was found in the gut and Contortylenchus reversus in the hemocoel of both D. pseudotsugae and D. rufipennis. The latter also had hemocoel infections of Sphaerulariopsis dendroetoni, which were not found concomitant with C. reversus infections. Contortylenchus brevicomi occurred in the hemocoel of D. brevicomis. The first report of a tylenchid larva parasitizing Trypodendron lineatum in North America is presented. Bursaphelenchus varicauda n.sp. was obtained from the gallery frass of D. pseudotsugae. It resembles B. corneolus and B. bestiolus but differs from the former species in female tail shape, the position of the excretory pore, spicule shape, and position of the male caudal papillae, and from the latter species in spicule shape and in the length of the esophagus and postuterine sac.  相似文献   

9.
Non-type material identified as Seinura winchesi, and deposited in the collection of the Nematology Department, Rothamsted Experimental Station, England, is described. The material was collected from mushroom compost in Leeds, England, in 1957. Females of this population are characterized by a set-off head, knobless stylet (20-21 µm), two rows of oogonia-oocytes, and absence of a postuterine sac. The median bulb is oblong and, at times, is constricted in the middle. The body is 565 to 675 µm long and tapers posteriorly to a pointed terminus. The cuticle is finely annulated, and there are three incisures in the lateral field. The ovary is outstretched and overlaps the esophageal gland lobes. A spermatheca is present, and spermatozoa are visible. The vulva is posteriorly located (V = 77-80), and a flap is absent. Males are 550 to 680 µm long with a spicate tail that bears three pairs of subventral papillae. The spike is short (14-18 µm), about one-half the tail length. The testis is 360 to 412 µm long, not reflexed, and at times overlaps the esophageal gland lobes. Spermatogonia-spermatocytes are in two rows. Spicules are 14 to 15 µm long with a prominent apex, and small rostrum. A bursa and gubernaculum are absent.  相似文献   

10.
11.
A nematode isolated from the termite Reticulitermes flavipes (Koller) was identified and described as a new genus and species, Neosteinernema longicurvicauda. Primary distinguishing characters, by contrast to members of the genus Steinernema, were females having prominent phasmids, a curved tail longer than the body width at the anus, a spiral shape in juvenile-bearing females, and juveniles becoming infective-stage juveniles before emerging from the female; males having prominent phasmids, a digitate tail tip, a characteristic shape of the spicules (foot-shaped with a hump on the dorsal side), and 13-14 pairs of genital papillae, with eight pairs preanal; and infective juveniles having prominent phasmids and a filiform curved tail as long as the esophagus. Adult nematodes are found outside the termite cadaver. Diagnosis of the family Steinernematidae was emended to accommodate the new species.  相似文献   

12.
Spicules of 9 Meloidogyne, 2 Heterodera, 3 Globodera, and 12 other plant-parasitic, insect-parasitic, and free-living nematodes were excised and examined using scanning electron microscopy (SEM). Gubernacula of some of the species were also excised, and their structure was determined. The two spicules of all species examined were symmetrically identical in morphology. The spicule typically consisted of three parts: head, shaft, and blade with dorsal and ventral vela. The spicular nerve entered through the cytoplasmic core opening on the lateral outer surface of the spicule head and generally communicated with the exterior through one or two pores at the spicule tip. Spicules of Xiphinema sp. and Aporcelaimellus sp. were not composed of three typical parts, were less sclerotized, and lacked a cytoplasmic core opening and distal pores. Spicules of Aphelenchoides spp. had heads expanded into apex and rostrum and had very arcuate blades with thick dorsal and ventral edges (limbs). Gubernaculum shapes were stable within a species, but differed among species examined. The accessory structures of Hoplolaimus galeatus consisted of a tongue-shaped gubernaculum with two titillae at its distal end and a plate-like capitulum terminating distally in two flat, wing-like structures. A comparison of spicules of several species of Meloidogyne by SEM and light microscopy revealed no striking morphological differences.  相似文献   

13.
14.
Recent inferences of phylogeny from molecular characters, as well as a reexamination of morphological and biological characters, reject the monophyly of the nematode genus Koerneria Meyl, 1960 (Diplogastridae). Here, Koerneria sensu lato is revised. The genus, which previously consisted of 40 species, is separated into three genera. Almost all of the transferred species are moved to the resurrected genus Allodiplogaster Paramonov & Sobolev in Skrjabin et al. (1954). Koerneria and Allodiplogaster are distinguished from each other by a weakly vs. clearly striated body surface, an undivided vs. divided stomatal cheilostom, and arrangement of the terminal ventral triplet of male genital papillae, namely in that v5 and v6 are paired and separated from v7 vs. v5–v7 being close to each other. Allodiplogaster is further divided into two groups of species, herein called the henrichae and striata groups, based on both morphological and life-history traits. The henrichae group is characterized by papilliform labial sensilla and male genital papillae, a conical tail in both males and females, and an association with terrestrial habitats and insects, whereas the striata group is characterized by setiform labial sensilla and male genital papillae, an elongated conical tail in both sexes, and an association with aquatic habitats. A second genus, Anchidiplogaster Paramonov, 1952, is resurrected to include a single species that is characterized by its miniscule stoma and teeth, unreflexed testis, and a distinct lack of male genital papillae or stomatal apodemes. Lastly, one further species that was previously included in Koerneria sensu lato is transferred to the genus Pristionchus Kreis, 1932. The revision of Koerneria sensu lato is necessitated by the great variability in its subordinate taxa, which occupy a variety of habitats, in addition to the increased attention to Diplogastridae as a model system for comparative mechanistic biology.  相似文献   

15.
Xiphinema llanosum n. sp. and Trophurus vultus n. sp. are described and illustrated from grass soils in Llanos Orientales, Colombia. Xiphinema llanosum is a bisexual species. The female body length is 2.3-2.7 mm, odontostyle 86-96 μm, and odontophore 58-65 μm long; vulva at 42-47%; anterior ovary is absent; the anterior uterus and oviduct are similar to the posterior branch but slightly reduced; and the tail is dorsally convex-conoid with a blunt hemispherical terminus. Male body length is 2.06-2.96 mm; spicules are 40-44 μm long; and four (rarely three or five) anterior ventromedian supplementary papillae are present. Trophurus vultus females are 0.52-0.67 mm long; vulva at 56-60%; stylet is 10.5-13.5 μm long; isthmus is as long as the basal esophageal bulb; the tail is subclavate, 1.6-2.2 times anal body width long; and the terminal cuticle thickness is about one-sixth of the tail length.  相似文献   

16.
Meloidogyne sasseri n. sp. is described and illustrated from American beachgrass (Ammophila breviliffulata) originally collected from Henlopen State Park and Fenwick Island near the Maryland state line in Delaware, United States (6). Its relationship to M. graminis, M. spartinae, and M. californiensis is discussed. Primary distinctive characters of the female perineal pattern were a high to rounded arch with shoulders, widely spaced lateral lines interrupting transverse striations, a sunken vulva and anus, and coarse broken striae around the anal area. Second-stage juvenile body length was 554 μm (470-550), stylet length 14 μm (13-14.5), tail length 93 μm (83-115), tapering to a finely rounded terminus. Male stylet length 20 μm (19-21.5), spicule length 33 μm (30-36). Scanning electron microscope observations provided additional details of perineal patterns and face views of the female, male, and J2 head. Wheat, rice, oat, Ammophila sp., Panicum sp., bermudagrass, zoysiagrass and St. Augustinegrass were tested as hosts. Distribution of the species was the coasts of Delaware and Maryland. The common name "beachgrass root-knot" is proposed for M. sasseri n. sp.  相似文献   

17.
Two new genera and species parasitizing passalid beetles from the Democratic Republic of Congo are described. Kongonema meyeri gen. n. sp. n. is characterized by having females with the cervical cuticle unarmed, first cephalic annule cone-like and truncate, sub-cylindrical procorpus and genital tract didelphic-amphidelphic. The males of Kongonema meyeri gen. n. sp. n. have the procorpus sub-cylindrical, the dorsal cuticle of the tail end thickened, a single large, median mammiform pre-cloacal papilla and a pair of small, pre-cloacal, sub-lateral papillae at a short distance before the level of the cloaca. Lubanema decraemerae gen. n. sp. n. is characterized by the body markedly fusiform, cuticle unarmed and strongly annulated, procorpus sub-cylindrical, isthmus as a constriction between procorpus and basal bulb, genital tract monodelphic-prodelphic and the posterior end rounded with a very short tail appendage.  相似文献   

18.
19.
A new species, Larinus berti sp. n. is described from Morocco and assigned to subgenus Cryphopus Petri, 1907 (Curculionidae: Lixinae; Lixini). Diagnostic characters of the new species are large size, elongate-ovate body, bisulcate sub-quadrangular rostrum, triangularly raised dorsum of rostrum, flat subgena and submentum, Y-shaped apodeme of sternite VIII of female and thin nodulus of spermatheca.  相似文献   

20.
Three new species in the super family Neotylenchoidea collected in Pakistan during 1979-80 are described. New species Nothotylenchus gohleni is related to N. affinis Thorne, 1941 but is differentiated by its longer, more robust body with tine cuticular annules, a more posterior vulva, inconspicuous basal knobs of the stylet, and poorly developed metacorpal area. N. geraerti and N. tuberosus are also close to this undescribed species, hut they have a more developed metacorpal area and a larger post uterine sac. Boleodorus zaini n.sp. is distinguished by its excretory pore open at a level with the base of the posterior esophageal bulb and by six distinct lines in the lateral field. Paurodontella sohailai n.sp. is closely related to P. densa (Thorne, 1941) Hussain &Khan, 1967 and P. minuta Hussain &Khan, 1967 but differs from them by its larger body, shape of tail, and seven incisures in the lateral field.  相似文献   

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