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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   

3.
Stephanofilaria thelazioides n. sp. (Filarioidea: Filariidae: Stephanofilariinae) is described from a hippopotamus Hippopotamus amphibius. This nematode is close to S. dinniki Round, 1964, a parasite of the black rhinoceros Diceros bicornis in Africa, but differs from it in the number of cuticular spines surrounding the mouth, the arrangement of the cloacal papillae and the measurements of the spicules, gubernaculum and microfilariae. Species of the genus Stephanofilaria possess spines on the head which have been derived by modification of the sensory papillae. S. thelazioides is the most primitive species of the genus and has the least modified arrangement of these papillae, with six bifid internal labial spines, four bifid external labial spines and four cephalic papillae. The genus appears to have diversified in various mammals which have in common a thick skin, such as rhinoceroses, elephants, buffaloes and now the hippopotamus. It appears to have become adapted secondarily to domestic bovines, initially in Asia and subsequently in North America.  相似文献   

4.
Summary A new mermithid nematode, Thaumamermis cosgrovei n. gen., n. sp. (Mermithidae: Nematoda) was found parasitizing two terrestrial isopods (Isopoda: Oniscoidea) in California. The hosts, Armadillidium vulgare (Latr.) (a pillbug) and Porcellio scaber (Latr.) (a sowbug) represent the first cases of isopods attacked by mermithid nematodes. The genus Thaumamermis can be distinguished from all previously described mermithids by the extremely dimorphic spicules, one being short and broad and the other long and filiform. It has been discovered that the nematodes are infected with an iridiovirus which commonly destroys the isopod hosts. ac]19800917  相似文献   

5.
Mesomermis camdenensis n. sp. is described from larvae of Simulium tuberosum (lundstroem) collected in Camden Valley Creek, Washington County, New York. This species possesses a barrel-shaped vagina, vulval flap. two short separate spicules, terminal mouth, six longitudinal chords, six cephalic papillae, large sexually dimorpbic anaphids, an esophagns of uniform width which extends for less than one-third of the body length, and a cone-shaped tail directed ventrally without appendage. Juveniles also are described and illustrated.A detailed morphological comparison with the mermithid M. flumenalis Welch is presented. The most pronounced morphological differences between these species are in the shape of the vulva, juvenile tail, and infective stage. Cross-mating trials support the integrity of the new species.The life cycle of M. camdenensis is closely synchronized with that of its primary host, S. tuberosum larvae. Infected S. tuberosum larvae were first collected in May. Emergence of postparasites from late instars took place from mid-June through mid-October. Sampling data indicate a lower susceptibility to infection among S. venuslum Say larvae.  相似文献   

6.
Summary Carnoya kermarreci n.sp. (Rhigonematidae; Nematoda) is described from Anadenobolus politus (Porat) (Rhinocricidae; Diplopoda) from Guadeloupe. The new species most closely resembles C. martiniquensis Adamson, 1984 from A. politus in Martinique and C. venezuelensis Adamson, 1984 from Rhinocricus flavocinctus from Venezuela in that the lips in the male are broad and the arrangement of caudal papillae is almost identical in the three species. Males of C. kermarreci are easily distinguished by the absence of spines, by the form of the cuticular projections at the base of the buccal cavity and by the fact that the most anterior pair of caudal papillae are located very close together. Females are distinguished by the presence of three pairs of somatic papillae near the level of the vulva. The nematode fauna of A. politus includes species from two distinct orders and presumably reflects the fact that diplopods are among the most ancient hosts of nematodes.  相似文献   

7.
《Journal of Asia》2000,3(1):19-24
Iotonchus onchus n. sp. is characterised by 2.4–2.5 mm long body; buccal cavity with posteriorly placed dorsal tooth at 72–77% of its length, dorsally swollen oesophageal collar, tuberculate cardia, presence of pre- and post-vulval papillae, muscular vagina without sclerotization and males with 11 pre-cloacal ventromedian supplement and 2 post-cloacal ventral papillae. Another species, I. litoralis reported here for the first time from Korea is also described in detail with variations in its buccal cavity length, tooth position and ‘a’ value.  相似文献   

8.
Thalassomermis megamphis n. gen., n. sp. (Mermithidae: Nemata) was extracted from sediment collected off the coast of Brazil at a depth of approximately 1,000 m. Although the food of this new nematode is unknown, the reduction of the stoma and esophagus and presence of a trophosome indicate that it is parasitic in its juvenile stages. Thalassomermis megaraphis n. gen., n. sp. is assigned to Mermithidae because of its similarity to that family in the appearance of the cephalic sensory receptors, the long and tubular vagina, and copulatory muscles of the male extending posteriorly throughout most of the length of the tail. Thalassomermis megamphis n. gen., n. sp. differs from all other members of Mermithidae by the large, lenticular, intracuticular amphidial fovea with coiled, emergent terminal filaments as well as the small amphidial aperture situated over the center of the fovea.  相似文献   

9.
Neocosmocercella fisherae n. sp. is the first nematode species found parasitising Phyllomedusa bicolor from the Brazilian Amazon Region. The new species has a triangular oral opening, with bi-lobed lips, and is distinguished from N. bakeri (triangular oral opening with simple lips), and from N. paraguayensis (hexagonal oral opening with bi-lobed lips). Additionally, the new species has ciliated cephalic papillae, which are absent in the other species of the genus. The reduced uterine sac and the presence of a single egg in the uterus in females are the main morphological characters that differentiate the new species from its congeners N. bakeri (8–10 eggs) and N. paraguayensis (10 eggs, based on the allotype). Additionally, the new species differs from the other two species of the genus by morphometric characters such as the size of spicules and gubernaculum in males and the vagina in females. Until now, phyllomedusid anurans are the only known hosts for the nematodes of this genus. The present work describes the third species of the genus and the first species of nematode parasitising P. bicolor.  相似文献   

10.
Angiostoma norvegicum n. sp. (Angiostomatidae) is described from the oesophagus, crop and the buccal mass of five species of slugs of the family Arionidae, Arion vulgaris (Moquin-Tandon), Arion ater (L.), Arion fasciatus (Nilsson), Arion fuscus (Müller) and Arion rufus/Arion ater hybrid), collected throughout Norway. Angiostoma norvegicum n. sp. was found parasitising arionids at seven of the 30 sample sites examined (23.3%), and 9.9% of all Arion spp. were infected with this nematode. The new species is characterised by its large size (4.0–8.6 mm long) and in having: lateral alae; 6 + 6 papillae at the cephalic end; a large circular mouth aperture; a spacious stoma; a pharyngeal basal bulb without valvular apparatus; an excretory pore near the base of bulb; a distal part of posterior ovary always outstretched; an anterior ovary distally nearly always outstretched; a vulva situated anterior to mid-body; long, nearly straight spicules and a small gubernaculum; three circumcloacal papillae and caudal genital papillae (GP) arranged in a pattern 1+2/3+3 with GP 5 and GP 8 opened on dorsal side of narrow bursa not reaching tail tip; short conical tails in both sexes with tips supplied by 4 short, unequal denticles. Morphologically, A. norvegicum n. sp. is similar to Angiostoma limacis Dujardin, 1845, which diagnostic characteristics are given based on examination of specimens from Norway and the UK. Conversely, the phylogenetic analyses based on D2D3 large subunit (LSU) rRNA gene sequences performed in the present study did not support the morphological affinity of these two species. Phylogenetic analyses demonstrated that although Angiostoma spp. cluster together, A. norvegicum n. sp. forms a tight monophyletic clade with the milacid nematode parasites Angiostoma margaretae Ross, Malan & Ivanova, 2011 and Angiostoma milacis Ivanova & Wilson, 2009.  相似文献   

11.
12.
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   

13.
A new nematode, Tripius gyraloura n. sp., is described from the arundo gall midge, Lasioptera donacis Coutin (Diptera: Cecidomyiidae). This gall midge is being considered as a biological control agent for use in North America against the introduced giant reed Arundo donax (L.) (Poaceae: Cyperales). Thus the present study was initiated to investigate a nematode parasite that was unknown at the time studies with L. donacis were initiated. The new species has a rapid development in the fly host and the mature parasitic female nematodes evert their uterine cells in the hosts’ hemolymph. Because large numbers of nematodes sterilise the host, eradication of the parasite from laboratory colonies of the midge may be necessary before populations of the fly are released.  相似文献   

14.
Infective larvae of the anisakine nematode Phocanema decipiens from the muscle of Atlantic cod (Gadus morhua) were fed to harbor seals (Phoca vitulina) and gray seals (Halichoerus grypus). During maturation in the stomach of seal hosts, P. decipiens molted twice; these molts are the third and fourth of its life cycle. The third molt occurred between the second and fifth days of infection. The third stage, i.e., infective larva entering the third molt, had a cuticular tooth ventral to the mouth; the fourth stage larva emerging from the third molt had three bilobed lips with dentigerous ridges. The fourth molt occurred between the 5th and 15th days in seals. A female nematode emerging from the fourth molt possesses a vulva and a vagina; a male possesses caudal alae, pre- and postanal papillae. Significant morphometric changes in nematodes were associated with both molts. Females and males of P. decipiens reached maturity after 15 to 25 days in seals. Ova were detected in the feces of the seal hosts as early as the 16th day.  相似文献   

15.
Based on light and scanning electron microscopical studies, a new nematode parasite, Lobocapillaria austropacifica n. sp. (Capillariidae), is described from the gall-bladder of the marine fish (obtuse barracuda) Sphyraena obtusata Cuvier (Perciformes: Sphyraenidae) from off the eastern Pacific coast of Australia, for which a new genus Lobocapillaria n. g. is established. This new genus is mainly characterised by a single row of stichocytes, the presence of two large, conspicuously elongated lateral caudal lobes and a pair of subventral papillae at their base in males, a flat spicule distended laterally towards its proximal end and provided with superficial rough transverse grooves, a spicular canal and a very long, aspinose spicular sheath with a conspicuous expansion near its proximal end when evaginated. Capillaria sphyraeni Parukhin, 1971 is transferred to Lobocapillaria as L. sphyreni (Parukhin, 1971) n. comb. A key to capillariid genera containing species parasitic in fishes is provided.  相似文献   

16.
Praecocilenchus rhaphidophorus n. gen., n. sp. is described as a new endoparasitic aphelenchoid nematode parasitizing adults of the palm weevil, Rhynchophorus bilineatus (Montrouzier). P. rhaphidophorus is unusual in that juveniles develop to maturity within the female uterus and thin, needle-shaped crystals form in the intestines of mature parasitic females. Hundreds of parasitic female nematodes were found in the body cavity of infected hosts. The role of this parasite as a biological control agent of Rhynchophorus weevils is discussed.  相似文献   

17.
A new species of mermithid nematode, Hexamermis popilliae n. sp. (Nematoda: Mermithidae) is described from the Japanese beetle Popillia japonica Newman in Italy, an area of new introduction for this invasive pest. The combination of the following characters separates H. popilliae from other members of the genus Hexamermis Steiner, 1924: adult head obtuse; amphidial pouches slightly posterior to lateral head papillae in female but adjacent to lateral head papillae in males; amphidial openings large, well developed; amphidial pouches elliptical in females and oblong in males; cuticular vulvar cone well developed, vulvar lips greatly reduced or lacking, vagina curved at tip where meeting uteri, without reverse bend (not S-shaped), spicules slightly curved, with a slight bend in the basal portion, approximately equal to body width at cloaca. This is the first record of a species of Hexamermis parasitizing the Japanese beetle Popillia japonica. The only previous mention of mermithid nematodes from P. japonica was an undescribed species of Psammomermis in North America. Hexamermis popilliae will be evaluated as a potential biological control agent in an integrated control program of the Japanese beetle in Italy.  相似文献   

18.
Hydromermis osami n. sp. (Nematoda: Mermithidae) is described from the hemocoel of 2 species of Rheotanytarsus chironomid imagos eclosing from Lake Ozawindib and Gulsvig Landing in northern Minnesota during August 2002 and June and July 2006. The species is distinguished from the other 26 described members of the genus by the terminal mouth; oval, opaque, thick walled amphids, wider than long; acute posterior end; single spicule not bifurcated proximally; well-developed uterine and vulval limbs of the S-shaped vagina; absence of bursal sleeve; absence of nutrient vesicles in the trophosome; and an esophagus length over 40% of body length. Members of the new species emerge from the hosts as adults. The other described Hydromermis species, number of specimens, location, and known hosts are tabulated.  相似文献   

19.
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   

20.
Hysterothylacium simile n. sp., collected from the Japanese seabass Lateolabrax japonicus (Cuvier) (Perciformes: Lateolabracidae) in the Bohai Sea off China, is described using both light and scanning electron microscopy. The new species differs from its congeners in the presence of narrow lateral alae originating a short distance posterior to the base of the ventrolateral lips, a long intestinal caecum (60.4–79.1% of oesophageal length) and a relatively short ventricular appendix (intestinal caecum to ventricular appendix ratio 1:0.58–0.85), long spicules (2.11–2.99 mm, 4.25–7.83% of body length), the number and arrangement of the caudal papillae (32–36 pairs arranged as follows: 27–31 pairs precloacal, 1 pair paracloacal, and 4–5 pairs postcloacal with the second or third pair double) and the presence of a particular midventral precloacal papilla. Specimens originally identified as Contracaecum paralichthydis Yamaguti, 1941 [now H. paralichthydis (Yamaguti, 1941)] by Xü (1957), collected from the yellow striped flounder Pseudopleuronectes herzensteini (Jordan & Snyder) (Pleuronectiformes: Pleuronectidae) in the Yellow Sea off China, were also re-examined. Their morphology clearly revealed they belong to H. aduncum (Rudolphi, 1802), which is also redescribed based on Xü’s material. In addition, the morphological variation of caudal papillae in H. aduncum from P. herzensteini was compared, using scanning electron microscopy, with specimens collected from another three fish hosts, Lophius litulon (Jordan) (Lophiiformes: Lophiidae), Scomberomorus niphonius (Cuvier) (Perciformes: Scombridae) and Cleisthenes herzensteini (Schmidt) (Pleuronectiformes: Pleuronectidae), from the Yellow Sea off China.  相似文献   

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