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1.
Summary

Echinonema australis sp. nov. is described from Sminthopsis crassicaudata, and differs most markedly from the only other species of the genus, E. cinctum, in lacking a swollen region with intermediate sized spines immediately posterior to the three circles of large spines which occur on the extreme anterior end of the body.  相似文献   

2.
《Journal of Natural History》2012,46(6):1249-1267
A comparative study on the development of Senegalese isolates of Schistosoma curassoni, S. haematobium and S. bovis in hamsters is reported, together with the compatibility of these parasites with Bulinus spp. and enzymes of adult worms.

The mean worm return from 35 hamsters exposed to 100 cercariae each of S. curassoni was 11·5%, and of these 54% were paired, the remainder were single males. The growth and maturation of the worms were recorded from 40 to 100 days. The cross-over point (when paired females are of the same length as paired males) was reached at 42 days post-infection when the worms averaged 13·7 mm in length. The majority of tissue eggs (84·5%) were recovered from the liver, compared with 11% in the colon, 2·5% in the caecum and 1·6% in the small intestine. Estimates of the fecundity of paired females averaged 167 eggs/day per female worm. Snail-infection experiments showed S. curassoni to be compatible with B. umbilicatus, marginally compatible with B. senegalensis and incompatible with B. forskalii, B. jousseaumei and B. guernei. S. curassoni is marginally compatible with B. bavayi, B. beccarii, B. camerunensis and B. cernicus, (members of the B. forskalii group) and B. obtusispira, a species placed in the B. africanus group. The mean worm return from 35 hamsters exposed to 100 cercariae each of S. haematobium was 9·1%, and of these 46·7% were paired, 42·1% were single male worms and the remaining 11·2% were single female worms. The growth of the worms was recorded from 40 to 100 days, the maturation from 60 to 100 days. The cross-over point was reached at about 62 days post-infection when the worms averaged 8·3 mm long. The majority of tissue eggs (95·3%) was recovered from the liver, compared with 2·8% and 1·9% from the small intestine and colon, respectively. Estimates showed that the average fecundity of paired females was 86 eggs/day per female worm. Snail-infection experiments showed that S. haematobium is marginally compatible with B. senegalensis, but incompatible with B. guernei and B. forskalii. The mean worm return from 35 hamsters exposed to 100 cercariae each of S. bovis was 26·6%, and of these 53·1% were paired, the remainder were single males. The growth and maturation of worms were recorded from 40 to 100 days. The cross-over point was reached just before 40 days: at 40 days the paired males averaged 9·5 mm in length, the paired female 9·6 mm in length. The majority of eggs (53·1%) was recovered from the liver, compared with 20·7% from the small intestine and 19·8% from the colon.

Estimates of the fecundity of paired females averaged 95 eggs/day per female worm. Snail-infection experiments showed S. bovis to be compatible with B. guernei, fairly compatible with B. forskalii, and marginally compatible with B. umbilicatus. B. senegalensis appeared to be sensitive to S. bovis under laboratory conditions with large numbers dying after one week of exposure.

Enzymes in 3017 extracts of adult schistosomes, obtained from natural and laboratory infections, have been analysed by isoelectric focusing. Enzymes studied include glucose 6-phosphate dehydrogenase (G6PDH), phosphoglucomutase (PGM), lactate dehydrogenase (LDH), acid phosphatase (AcP), malate dehydrogenase (MDH), hexokinase (HK) and glucose phosphate isomerase (GPI). S. bovis was clearly differentiated from S. haematobium by patterns of G6PDH, GPI, HK and AcP. Similarly, S. bovis and S. curassoni were distinguishable by the different patterns of PGM, GPI, HK and AcP. S. haematobium and S. curassoni were differentiated by patterns of PGM and HK. Heterogeneity was seen in all species. In a natural infection of a sheep S. bovis and S. curassoni were found paired together.  相似文献   

3.
Résumé

1. 1. There is a symbiosis between Sertularia operculata and Squalus acanthias, and between Seralia lendigera and Hippocampus ramulosus—there being but a single case reported for each pair of organisms. It is probable that these associations are entirely accidental.

2. 2. Of Stylactis minoi and Minous inermis, no fewer than twenty-nine specimens of the fish (presumably all ever taken) wherever found—and they have been taken from five widely distant stations on both coasts of India, and from Japan—were infested with the hydroid. Furthermore, so far as known, this particular hydroid has never been found save on this particular fish (inermis). These facts would seem to indicate that this is a purposive or obligate symbiosis.

3. 3. About one hundred specimens of Hypsagonus quadricornis were taken in Puget Sound. Thirty-seven of these were preserved, and ten of them were found to be sparsely covered with Perigonimus pugetensis. Other specimens of the fish taken outside Puget Sound and in Behring Sea all lacked the hydroid. Consideration of all these facts leads to the conclusion that the association is symbiotic and more or less accidental.

4. 4. One case has been presented of Hydrichthys mirus attached to Seriola zonata in Narragansett Bay. Parasitism is alleged, but the proofs offered, that there was some apparent degeneration on the part of the hydroid and some slight evidence of wasting away of the muscles of the fish at the point of attachment, are at best inconclusive, there being no evidence from sections presented to show actual anastomosis of the tissues of the two organisms. From the evidence presented one must conclude that this is only a case of symbiosis.

5. 5. One case is known of the attachment of a Nudiclava to a fish, Monacanthus, from the Andaman Sea. Parasitism is alleged in the title of the paper, but disclaimed in the text, since, in sections cut through the basal plate and the skin to which it was attached, such was not proven. Furthermore, the finding of food in the hydranths discounts the idea of parasitism. This case also must be classed as a symbiosis.

6. 6. True parasitism has been repeatedly shown to exist between an aberrant hydroid, Polypodium hydriforme, and the ovarian eggs of the Volga sterlet, Acipenser ruthenus. This has been definitely established by the work of four investigators, extending in time from 1872 to 1922—a half century. Except in its earliest stages, Polypodium has the nutritive cell-layer of its stolon, the endoderm, on the outside bathed in the egg-yolk. Later this becomes inverted and a large amount of yolk is carried into the common cavity. The egg is used up in nourishing the parasite.

7. 7. True parasitism has been shown between Hydrichthys boycei and numerous individuals of three species of fishes—Ambassis natalensis, Mugil sp., and an undetermined fish belonging to the Glyphidodontidæ—in Durban Bay, South Africa. The parasites were attached to various parts of the fishes, especially the fins. At the points of attachment, haustoria were sent down into flesh and into blood-vessels, and by means of these the parasite fed on the tissues of its host. Furthermore, on none of the hydranths were tentacles ever found, nor was any food ever found in them. Strange to say, the parasite never covers any large area of the fish, and apparently presently drops off leaving a scar behind.

  相似文献   

4.
Summary

Ctenogobius veliensis, a new species of gobiid fish is described from the South-West coast of India. The characters of the fish conform to those of the genus Ctenogobius Gill but differ markedly from those of other recorded species of the genus. Apart from the usual, external morphological, morphometric and metistic characters, several other features such as the cephalic-lateralis system, skeletal features and morphology of the alimentary canal are also studied and have been found to be of significance for identifying the species. The fish shows distinct sexual dimorphism in many features.  相似文献   

5.
《Journal of Natural History》2012,46(5):1119-1128
Features of sea snakes (Emydocephalus and some Aipysurus) that specialize in eating fish eggs are reviewed. Additionally, an earlier account of the hyoid musculature of Aipysurus eydouxi is corrected.

A new feeding mechanism, possibly unique in higher snakes, is postulated; fish eggs together with substantial quantities of sand appear to be sucked into the mouth by the contraction of a ‘geniomucosalis’ muscle which originates on the lower jaw and inserts on the oral mucosa. Other characters, which occur in two of the three egg-eating species, and which seem to correlate with this feeding habit, include: a spine on the snout (perhaps used for probing sand), strong consolidation of lip scales (likely to increase rigidity of the mouth border) and marked tooth reduction and loss (probably reflecting redundancy).  相似文献   

6.
Summary

Information obtained about the association of various flies with different types of filth in Dacca city, their life histories, food preference of the larvae, and the seasonal changes of their population has been recorded.

The filth of Dacca city has been classified into the following eight categories for the present work. (1) Human excrement, (2) cow dung, (3) manure heaps, (4) garbage and kitchen refuse, (5) decaying fruits and vegetables, (6) carrion, (7) rotten fish and meat, and (8) municipal sewage and other liquid waste.

In total nine fixed areas in different parts of the city were visited regularly to collect adult flies, or their eggs or larvae.

The association of various flies with the above eight types of filth has been discussed.

The duration of the life cycle from oviposition to emergence of the adults was recorded for five species of Psychoda, seven species of Musca, one species of Calliphora, two species of Chrysomyia, two species of Lucilia, and three species of Sarcophaga, during summer and winter.

Food preferences of the larvae of two common species of Musca, two species of Sarcophaga, one species of Lucilia, one species of Calliphora, and two species of Chrysomyia have been recorded.

The trend of the seasonal variation of the various fly populations have been discussed.  相似文献   

7.
Males of two undescribed Encarsia species were reared from eggs of two cicadellid species during a study of egg parasitoids of corn leafhopper, Dalbulus maidis (DeLong and Wolcott) in northwestern Argentina. Samples were collected during the summer of 2004–2007 using sentinel eggs, and several males of a new species of Encarsia (Hymenoptera: Chalcidoidea: Aphelinidae) were obtained. A single male of a closely related Encarsia species, also previously undescribed, was reared from an egg of another cicadellid on maize, Plesiommata mollicella (Fowler). These are the first records of any Encarsia species reared from eggs of Cicadellidae. The two new species are described as Encarsia dalbulae Polaszek and Luft Albarracin sp. nov., and Encarsia mollicellae Polaszek and Luft Albarracin sp. nov.  相似文献   

8.
《Journal of Natural History》2012,46(33-34):2173-2192
Variations in reproductive modes, egg production, and the effects of parental care on hatching success are compared between Pleioplana atomata and Imogine zebra. Pleioplana atomata transfers sperm via true copulation, whereas I. zebra dermally impregnates spermatophores onto the dorsal surface of partners. Pleioplana atomata lays up to 750 large eggs over a 6‐week period, and I. zebra individuals lay up to 1346 small eggs in 12 days. Female fecundity is positively correlated with body size in both species. Developmental time lines are temperature‐dependent, and juvenile worms hatch after 3 and 6 weeks for I. zebra and P. atomata, respectively. Covering of egg masses by the adult is observed for both species and although this parental care is not necessary for egg development or hatching, it plays a significant role in the hatching success of P. atomata. In I. zebra, parental covering of egg masses may play a role in eggshell development.  相似文献   

9.
《Journal of Natural History》2012,46(23-24):1385-1393
ABSTRACT

Two specimens of the endemic land flatworm species Othelosoma impensum Sluys & Neumann, 2017 from the volcanic island São Tomé were observed in the wild in Obo-National Park while they were preying on ants that had descended on a tree trunk after their nuptial flight. A maximum of 41 ants were assembled in a cluster by one of the flatworms, the insects being immobilised by mucus secreted by the worms. A strong cephalic retractor muscle facilitated capture of the mobile prey. Presence or absence of similar cephalic adaptations in other species of Othelosoma and other genera of land flatworms is discussed, as well as the effectiveness of the sticky mucus secreted by the worms during prey capture.  相似文献   

10.
A survey of 5722 sheep and 1752 goats at the abatoir in Dakar, Senegal showed that the overall prevalence of schistosomiasis was 2·1%. Of the 112 animals where identification of the schistosome species was possible, all were infected with Schistosoma curassoni, and 2·7% had mixed infections with S. bovis. The adult worms of S. curassoni are described, and on the basis of egg morphology this species is shown to be distinct from S. bovis and S. mattheei. Eggs of S. curassoni measured 146 μm ± 16·8 × 63·3 μm ± 4·5 from sheep and 149·4 μm ± 13·2 × 62·8 μm ± 4·9 from mouse liver, and appear to be indistinguishable from the eggs of S. haematobium Guede Chantier, Senegal which measure 153·1 μm ± 11·1 × 62·4 μm ± 12·1 from mouse liver. However, S. curassoni differs from S. haematobium in that it develops more quickly than S. haematobium in hamsters, uterine eggs becoming visible at least 20 days earlier; the adult worms of S. curassoni are nearly double the size of S. haematobium in hamsters at 70 days post infection.

Also, S. curassoni develops well in sheep and cattle unlike S. haematobium, but will not develop to maturity in baboons like S. haematobium.  相似文献   

11.
Summary

A population of Chaetogaster limnaei limnaei Gruffydd, living on various molluscs in the Worcester-Birmingham canal, was studied from February 1971 to February 1973 in the course of a detailed study of the digeneans parasitizing the molluscs.

The incidence of C. l. limnaei on each of its hosts was recorded for each month during the sampling period.

The incidence of the worms was high during the winter months on Physa fontinalis (and Lymnaea peregra) but low during the summer, and was high during the summer and low during the winter on Bithynia tentaculata.

It is postulated that this pattern of incidence may have been due to a migration of the worms from the pulmonate hosts to B. tentaculata in late spring, when the large pulmonates died after breeding, and a return migration to the pulmonates the following autumn.

There was found to be no association between the digeneans parasitizing the molluscs and the occurrence of the oligochaetes, and it is suggested that in this case the oligochaetes have no influence on the parasitic burden of the molluscs.  相似文献   

12.
Synopsis

A new species of Argyrophylax, parasitic on the Banana Scab-Moth Nacoleia octasema Meyrick, is described and the Oriental and Australasian species of this genus are reviewed; a key is given for their identification. Six species and a subspecies hitherto placed in other genera are here assigned to Argyrophylax, and seven new combinations are established; two specific names are newly placed in synonymy.  相似文献   

13.
Summary

Examination of ascaridoid nematodes from the osteoglossid fish Scleropages jardini in Papua New Guinea revealed that they belong to a new species and named Brevimulticaecum scleropagi nov. sp. Multicaecum heterotis Petter, Vassiliades and Marchand, 1979 from the African osteoglossid fish Heterotes niloticus was moved to the genus Brevimulticaecum in new combination and reported from the same host in Nigeria and Sudan for the first time. The new species is near to B. heterotis but differs from it in having lips that are not lobed, in the absence of the cervical alae, the much smaller size and measurements of the various organs.  相似文献   

14.
Summary

Specimens of Notoscolex camdenensis, the type-species of Notoscolex are described for the first time since erection of the genus. The type-species is shown to have stomate megameronephridia median to micromeronephridia in posterior segments, a condition indicating that its affinities lie with a Dichogaster-Megascolides group of genera and not, as has previously been held, with a Megascolex group. Only four other species appear to be congeneric with N. camdenensis. These are endemic in New South Wales, like the type-species, or in Queensland.  相似文献   

15.
《Journal of Natural History》2012,46(39-40):2511-2552
ABSTRACT

This paper, which presents an annotated checklist of the nymphalid subfamily Heliconiinae, is the fifth in a series on the butterfly fauna of Mount Kilimanjaro. Three genera of Heliconiinae (Acraea, Phalanta, Issoria), with a total of 12 included species, are known or believed to occur within the main forest zone, from ca 1800 to 2800 m. Of these, only two species (Acraea acuta, Issoria hanningtoni) may be restricted locally to this primary forest. The lower slopes fauna, below 1800 m, is considerably richer, with a total of four genera and 33 confirmed species listed (10 of which species extend into the forest zone). Possible additional species of Acraea, including some doubtful earlier records, are noted and discussed. An identification key to the genera of Heliconiinae that occur in Tanzania, together with a key to the adults of all heliconiine species considered to occur or likely to occur on Kilimanjaro, with 280 colour images, are included as online Supplementary Information.  相似文献   

16.
Summary

The burrow-dwelling jawfish, Lonchopisthus micrognathus, occurs at 12–40 m depths on sandy-mud substrates in back reef areas off southwestern Puerto Rico. Its behaviour is remarkably similar to Opistognathus aurifrons. It feeds on suspended material in the water. The burrow has a primary opening with a vertical tube and smaller accessory openings. A crab, Chasmocarcinus cylindricus, occurs with it. Lonchopisthus micrognathus broods its eggs orally and may spawn the year round. Availability of suitable sediment is not limiting distribution of the species.  相似文献   

17.
The reproduction and parasite associates of the squat lobster Munidopsis platirostris (A. Milne Edwards and Bouvier, 1894) were investigated based on collections made in the Bahamas and Curaçao with grassmat and bundled fishing net traps used to collect sipunculan worms and other small invertebrates. Size of ovigerous M. platirostris was significantly correlated with clutch size for females from both localities but females from the Bahamas produced significantly more eggs (on average 10.1 eggs/clutch) than females from Curaçao (on average 6.6 eggs/clutch). Early embryos of M. platirostris from the Bahamas were 0.74–0.82 mm in diameter, similar to some other species of Munidopsidae as well as Chirostylidae. Two species of crustaceans, another squat lobster and a leptostracan, as well as a limpet mollusc, were collected with M. platirostris in the Bahamas, while a sipunculan was an associated species in a Curaçao collection. One specimen of M. platirostris had an unidentified cryptoniscoid epicaridean isopod, possibly representing a new genus and species. Two specimens of M. platirostris each had one rhizocephalan externa of a species belonging to Lernaeodiscus Müller, 1862 but their morphology does not match that of L. schmitti Reinhard, 1950, the only species in the genus known from squat lobsters in the western Atlantic. Additional materials and tools, such as DNA analysis, are needed to describe these potentially new parasites and we suggest that use of these traps may be an effective method to obtain additional samples.  相似文献   

18.
Summary

The discovery of Serolis tropica sp. nov. in the shallow shelf zone of the Pacific of Panamá, just south of 9°N latitude, establishes the first occurrence of the Serolidae in tropical American waters. Since gravid females were found in cool as well as warm thermal seasons, it is assumed that this species is adapted to live under tropical conditions. Serolis yongei, known from the Great Barrier Reef, was collected at a depth of 200 m. It is not presently known if this species, like S. tropica, also inhabits the shallow shelf where warm-water conditions prevail.

Serolis tropica, a member of the North American ‘carinata’ group, is related to the ‘marplatensis’ group of South America. While it is argued that these two groups must have shared a common history, the remaining region of approximately 40° latitude between the northern and southern forms greatly complicates the relationship. Whether or not this gap is real or due to a lack of fine, inshore sampling can only be determined by further field work in this region.  相似文献   

19.
Summary

Ceratocuma cyrtum sp. nov., from the Bay of Biscay region, is described, and the related form C. amoenum Jones, 1969 redescribed. Notes are made on the morphology of other members of the genus. Diagnoses of the family Ceratocumatidae and its component genera are revised.  相似文献   

20.
Summary

A method for culture of Ephippiger cruciger is given which enables the insect to be available more or less continuously in spite of the fact that in the wild it is a biennial species. Procedures for hastening the embryonic and diapause developments, conversely for holding eggs in storage for long periods, are given. A brief survey of published work, on this insect, together with consideration of some potential uses, is included.  相似文献   

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