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1.
Surface structures of males and females of Setaria labiatopapillosa were studied by means of scanning electron microscopy at high magnification. It was found that the surface of buccal cavity, lateral appendages, vulva, anus and cloaca differs from the remaining cuticle. The shape of internal and external mouth papillae, amphids, deirids, postdeirid and phasmidial pore was studied. On the surface of the postdeirid are four small papillae arranged in a typical manner around the depression from which projects a needle-like formation. The ventral bands are formed by fine longitudinal parallel folds of the cuticle. Some anomalies in the localization of postcloacal papillae were observed.  相似文献   

2.
Heliocotyle ewingi sp. n. (Monogenea: Monocotylidae) is described from the gills of Myliobatis australis Macleay, 1881 (Myliobatididae) collected from Norfolk Bay near Hobart, Tasmania, Australia. Heliocotyle ewingi can be distinguished readily from the only other species in the genus, Heliocotyle kartasi Neifar, Euzet et Ben Hassine, 1999, by the presence of a single pseudoseptum on each of the peripheral loculi except the posteriormost, eyespots and by the morphology of the male copulatory organ which is a short, straight sclerotised tube which lacks a sclerotised accessory piece. The generic diagnosis is revised to accommodate the new species and the anterior glands are discussed.  相似文献   

3.
Based on satellite images and historical vegetation maps, Phragmites australis (common reed) in the Liaohe Delta, in north-east China, has expanded from 78 078 ha in 1984 to 91 262 ha in 2006, averaging over 600 ha year−1. This study also attempted to elucidate the reason for this expansion, using both historical documents and field surveys. The results suggested that the expansion of P. australis was driven mainly by human activities. Freshwater irrigation reduced soil salinity; irrigation of land blocks divided by canals and ditches (square-land irrigation) maintained optimal temperature, water and oxygen for the growth of P. australis ; deep freshwater irrigation and seawater irrigation eliminated some weeds; combined irrigation and burning eliminated an insect pest. These examples in the Liaohe Delta showed that water, salinity, oxygen, temperature and insect pests were important ecological factors that affected the growth of P. australis . By harmonising these ecological factors, optimal conditions were created for the natural expansion of P. australis and promoted the formation of monospecific stands of P. australis .  相似文献   

4.
The tapeworm Caryophyllaeides ergensi sp. n. (Cestoda: Caryophyllidea) is described from Leuciscus leuciscus baicalensis from the River Selenga basin in Mongolia. It differs from the only hitherto recognized species of the genus C. fennica (Schneider, 1902), mainly in its extremely long uterus with coils extending anteriorly to anterior half, sometimes up to anterior third of the body of gravid specimens.  相似文献   

5.
Abstract: Two new species of bothriocephalidean cestodes, Clestobothrium splendidum sp. n. from Merluccius australis (Hutton) and Clestobothrium cristinae sp. n. from Merluccius hubbsi Marini from the Patagonian shelf of Argentina, are described. Clestobothrium splendidum can be typified by the following characteristics: a medium-sized strobila composed of410-528 proglottides that are much wider than long; 49-90 testes per mature proglottis, partially surrounding the ovary posteriorly; a transversely elongated genital pore situated anterior to spurious articulations; presence of a genital atrium; a globular cirrus-sac occupying 4-6% of mature proglottis width; a vagina with sphincter and three pairs of osmoregulatory canals on each side of the proglottis. Clestobothrium cristinae is characterised by its small size; 71-219 proglottides; 39-64 testes per mature proglottis, usually surrounding completely the ovary posteriorly; a rounded genital pore situated at the same level of spurious articulations; an oval cirrus-sac occupying 8-16% of mature proglottis width; and three pairs of osmoregulatory canals on each side of the proglottis. Clestobothrium cristinae shares with C. splendidum the type and distribution of microtriches, except for the central surface delimited by two lips. Additionally, type and voucher materials of Clestobothrium crassiceps (Rudolphi, 1819) from Merluccius merluccius were studied. A key to species is provided.  相似文献   

6.
A new genus of fish blood flukes (Aporocotylidae Odhner, 1912) is proposed for a species found on reefs surrounding Lizard Island on the northern Great Barrier Reef. Rhaphidotrema kiatkiongi gen. et sp. n. was recovered from the heart of the stars-and-stripes pufferfish, Arothron hispidus (L.) (Tetraodontidae). Rhaphidotrema kiatkiongi is notable as the first digenean reported to possess a penis stylet. It also differs from all other aporocotylid flukes in having a combination of 18-19 testes in a group at the ends of the intestinal caeca, a broad lanceolate body shape with a dextrally-directed posterior bend at the level of the male genital pore, and separate genital pores, with the female genital pore distinctly sinistral and the male genital pore slightly dextral to midline. This is the second species of aporocotylid fluke reported from this pufferfish.  相似文献   

7.
Monostephanostonum nolani sp. n. is described from Carangoides plagiotaenia Bleeker, off Lizard Island, Great Barrier Reef, Queensland, Australia. It differs from all other species in the genus except M. manteri Kruse, 1979 in that the vitellarium reaches into the forebody. It differs from M. manteri in the ventral hiatus in the circum-oral spine row, the extent of the vitellarium in the forebody, where it is not confluent, its elongate pharynx and its smaller eggs. Monostephanostoinum krusei Reimer, 1983 is redescribed from Pseudocaranx dentex (Bloch et Schneider) from Ningaloo Reef off Western Australia. It is considered similar to M. nolani, differing in the vitellarium being restricted to the hindbody, but sharing with M. nolani an unusual arrangement of small body-spines on the antero-ventral surface. It is also morphologically very similar to Monostephanostomum roytmani (Parukhin, 1974), which apparently lacks the diminutive antero-ventral body-spines. A key to eight recognized species in the genus is presented.  相似文献   

8.
The effects of temperature and photoperiod on Emex australis and E. spinosa were studied in a pot experiment. E. spinosa was more precocious than E. australis in terms of earlier flowering, runner and seed formation under conditions similar to those of daylength and mean daily temperatures in the field and it produced three times more seeds. Optimum day/night temperatures for both species, however, were between 15/10 and 20/15°C. Both the lowest (10/5°C) and highest (30/25°C) temperatures tested delayed flowering and there was a terminal necrosis of runners at high temperatures. Flowering in both species also was generally hastened and seed production greater at the longest photoperiod (16 h) compared with the shortest (8 h). The results are discussed in terms of the distribution of E. australis, the similar environmental requirements of both species and the possible encroachment of the less desirable E. spinosa, which is as yet more restricted in distribution in Australia, into areas already colonised by E. australis.  相似文献   

9.
甘薯小象甲是国内外重要的检疫性害虫,除本身为害薯块外,引起的伤口还会诱致病菌侵入,使受害薯块发生恶臭和苦味无法食用。准确鉴定云南地区的甘薯小象甲,特别是研究其遗传变异可为检疫提供依据。本研究采集了云南元谋县甘薯小象甲,采用Chelex-100法快速提取甘薯小象甲基因组DNA,分别对雌雄成虫rDNA ITS-1序列进行系统发育分析,首次发现云南元谋县的甘薯小象甲属于东亚分支的东南亚亚支,与我国之前报道的甘薯小象甲属于东亚分支的东北亚亚支不同,说明云南元谋县的甘薯小象甲种群来源与中国广东、福建、浙江和重庆的种群来源不同。  相似文献   

10.
Three new genera of eutetrarhynchid trypanorhynch cestodes are described from Mobula spp. (Mobulidae) from the Gulf of California, Mexico. Fellicocestus mobulae gen. et sp. n. from the gall bladder of Mobula japonica (Miller et Henle) is distinguished by elongate bothria, a pars bothrialis equal in length to the pars vaginalis, masses of gland cells in the pars vaginalis and an heteromorphous armature in which hook rows arise from a central file of hooks on the bothrial surface of the tentacle and terminate in a central file on the antibothrial surface. Species of Mobulocestus gen. n. occur in the nephridial system and cloaca of rays and are characterized by two bothria, an heteroacanthous armature with hook rows beginning on the bothrial surface and terminating on the antibothrial surface, and by hooks at the beginnings of rows with an apical cavity. M. nephritidis sp. n. and M. lepidoscolex sp. n., both from the nephridial system of Mobula thurstoni (Lloyd) are differentiated by testis number and by the presence of scale-like microtriches on the tegument of the scolex of M. lepidoscolex. M. mollis sp. n., from the cloaca of Mobula thurstoni is distinguished by testis number (97-111 in M. lepidoscolex, 20-22 in M. nephriticus and 48-70 in M. mollis). Hemionchos gen. n. from the spiral valve of Mobula spp. has two bothria, an heteroacanthous armature, hook rows arising on the bothrial surface and terminating on the antibothrial surface and hooks at the beginning of rows with an apical cavity. It differs from Mobulocestus in having a distinctive basal armature and both hook files 1 and 1' on the bothrial surface, but has an additional, small, satellite hook adjacent to each hook 1'. H. striatus sp. n. from the spiral valve of Mobula thurstoni and M. japonica is differentiated by having a basal armature of closely packed arrays of small, uncinate hooks. H. mobulae sp. n. from the spiral valve of Mobula japonica and M. munkiana Notarbartolo di Sciari, differs in testis number and in having large, flattened hooks in the basal armature. H. maior sp. n., from the spiral valve of M. japonica, is larger, differing in both the number of testes and in the basal armature.  相似文献   

11.
The morphological and metrical variability of hard parts of opisthaptor was studied in the representatives of local populations of Gyrodactylus aphyae Malmberg, 1957 and G. macronychus Malmberg, 1957. The changes within the range of variability, which were observed during the year, correspond to regular and periodical changes in the environmental temperatures. The hard parts of opisthaptor were much smaller in specimens occurring during warm seasons than in specimens occurring during cold seasons. The temperature of about 8 degrees C forms a boundary between warm and cold seasons. The author assumes that similarly as G. aphyae and G. macronychus also other members of the genus Gyrodactylus living in climatic zones with regular change of seasons will react similarly on the annual variation in the environmental temperatures.  相似文献   

12.
A new copepod species, Acanthochondria sagitta sp. n., is described based on specimens collected from the flounder Xystreurys rasile (Jordan) (Pleuronectiformes, Paralichthyidae), caught in the coastal waters off Necochea, Buenos Aires Province, Argentina. The new species differs from its congeners by the following combination of characters: presence of three pairs of cephalic outgrowths; the triangular shape of the trunk with diverging postero-lateral processes; leg 2 of an intermediate shape between Types C and D, which projects laterally from the trunk, and Type B-V antennule bearing two proximal processes (one ventral and one dorsal) on the swollen basal portion.  相似文献   

13.
A new species,Tamarixia sheebae, is described and illustrated.Tamarixia sheebae differs fromT. bicolor Mercet andT. radiata Waterston in having the apex of gaster tilted upwards. It emerged from leaf galls ofTerminalia arjuna (Roxb.) Wright & Arn. (Combretaceae), a tree with many medicinal properties in addition to its timber value.  相似文献   

14.
A new species, Gnathia nkulu sp. n. is described from material collected off the South African coast at 80-200m depth. It differs from the intertidal species Gnathia africana Barnard, 1914 in that the mediofrontal process is not deeply divided into two lobes, article 2 of the pylopod is rounded and small wart-like tubercles and long simple setae are present on both the cephalosome and pereon.  相似文献   

15.
In the region of the Barun Glacier, in the vicinity of the Makalu Mountain in the Great Himalaya (Nepal) two mite species of the family Myobiidae, Protomyobia kounickyi sp. n. and Radfordia lemnina (C. L. Koch, 1841) were found on Soriculus caudatus soluensis (Gruber) and Alticola roylei (Gray) respectively at high altitudes (3450--4900 m). A single specimen of the latter species slightly differs from specimens from the typical host, Clethrionomys glareolus (Schreber), in a greater length of l4 and d5 and in the form of coxal setae I, but it is not regarded as a different taxon.  相似文献   

16.
17.
Helminthological examination of the snaggletooth shark, Hemipristis elongata (Klunzinger) (Carcharhiniformes: Hemigaleidae), from Moreton Bay, Queensland, Australia, yielded a phyllobothriid genus and species previously unknown to science. Hemipristicola gunterae gen. n., sp. n. is described here, and is placed in the subfamily Phyllobothriinae Braun, 1900. Of the other phyllobothriid genera, the new genus most closely resembles Paraorygmatobothrium in that both genera possess bothridia with a single loculus and apical sucker, post-vaginal testes and lateral vitellarium. Hemipristicola, however, differs from Paraorygmatobothrium in the morphology of the proximal bothridial surface microthrix, possessing serrate gladiate spinitriches with marginal serrations restricted to the distal half of the blade, and in the possession of a more extensive uterus, extending anteriorly from the anterior margin of the ovary to well past the level of the cirrus-sac. The new genus also differs from Paraorygmatobothrium by possessing testes that are more than one layer deep. Hemipristicola gunterae further differs from Paraorygmatobothrium species found in hemigaleid sharks in possessing vitelline follicles arranged in two lateral bands that are restricted to the lateral margins of the proglottid and not possessing a cephalic peduncle. Bayesian inference analysis of partial 28S rDNA data shows that H. gunterae forms a sister taxon to species of Paraorygmatobothrium. These two genera were resolved with high posterior probability support in the analysis. Hemipristicola gunterae is only the second phyllobothriid species to be described from Hemipristis elongata from Australian waters, and the fourth from the Australian hemigaleids.  相似文献   

18.
Acolpenceron australe sp. n. (Dactylogyridae, Dactylogyrinae) is described from ureters and renal tubules of Percichthys trucha (Cuvier et Valenciennes) (Perciformes, Percichthyidae) from Andean Patagonian lakes. The new species has a haptor with 14 hooks, with shanks comprised of two subunits. It has overlapped intercaecal gonads, male copulatory organ as a sclerotized tube with one counterclockwise coil and a J-shaped accessory piece. It differs from the other species of Acolpenteron by having a non-forked accessory piece. This is the first monogenean species described from a percichthyid host in South America.  相似文献   

19.
A new strain of broad bean mottle virus, isolated from faba bean (Vicia faba L.) in the Sudan, is described. It differs considerably from known isolates by its nearly symptomless infection of faba bean in spite of high concentrations of the virus in infected plants. It does not differ from regular isolates in gel-diffusion serology, light and electron microscopy, host range and symptoms in major hosts other than faba bean. It may constitute a potential threat to other food legumes in the region.  相似文献   

20.
A new nematode species, Paraphilometroides nemipteri sp. n. is described from the female specimens collected from the dorsal fin and operculum of the marine perciforme fish, Nemipterus peronii off Kuala Terengganu coastal waters in Malaysia. It considerably differs from all other species in Philometridae in the structure of the head end (presence of wide dorsal and ventral cephalic cuticular alae supported by special inner transverse muscular formations) and, therefore, a new genus Paraphilometroides gen. n. has been erected to accommodate it. Additional characteristic features of P. nemipteri are the presence of cuticular bosses on the body, eight cephalic papillae in the outer circle and four small papillae in the inner circle, and the absence of caudal protrusions.  相似文献   

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