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1.
A new species of Placobdelloides is described from crocodiles and river turtles in the Singapore Zoological Gardens. Placobdelloides stellapapillosa is three annulate, has one pair of eyes on somite I or II, six pairs of testisacs, two annuli between the gonopores, one post anal annulus, seven pairs of lobed crop caeca and 12–14 unique star-shaped papillae on the dorsal surface of each annulus. Star-shaped papillae on annulus a2 are typically larger and more pronounced than on annuli a1 and a3. Additional minute cone-shaped papillae may occur between the larger star-shaped papillae or may replace these papillae on annuli a1 and a3. Eggs and young (100–200) are attached by their posterior suckers directly to the ventral surface of the parent.  相似文献   

2.
A new freshwater leech species, Helobdella nilae, is described with diagnostically a dorsal nuchal gland (scute) on somite VII, five pairs of simple crop caeca, the last pair extending posteriorly as postcaeca, five pairs of compact spherical testisacs, an unpigmented dorsal surface lacking both papillae and sensilla. The mouth is subapical and surrounded by numerous single or paired pits (pores).  相似文献   

3.
Collections made in montane forests of the Bicol region of the Philippine island Luzon contained earthworm species new to science. The new genus Dendropheretima has intestinal caeca paired in xxv, lamellar oesophageal pouches in xi‐xiii, testes free of sacs, and last hearts in xii. The two species, D. banahawensis and D. bicolensis, are both arboreal. A second new genus Isarogoscolex contains two species, Isarogoscolex abiadai and I. albayensis which are also arboreal but have more posteriorly located caeca and more pairs of caeca, have only meganephridia in the intestinal segments, and the lamellar oesophageal pouches are arranged differently from Dendropheretima. Among the other genera of the Pheretima complex, these new taxa may be closest to the Australo‐Papuan Begemius.  相似文献   

4.
Hemiclepsis quadrata, which is the only representative of the genus so far reported in Africa, is redescribed. Illustrations showing the diagnostic features of the taxon are provided for the first time. A thorough study of the holotype and one of the paratypes, as well as additional specimens, revealed that Moore overlooked certain important taxonomic features when he described the leech as a Batracobdella species. The transfer of this species to the genus Hemiclepsis is based on the following features exhibited by this leech: dilated head region, three pairs of eyes, central proboscis pore, ten pairs of crop caeca and small genital atria.  相似文献   

5.
The proliferative activity of the pyloric caeca of Asterias rubens was investigated. Autoradiographic experiments using intracoelomically injected (methyl-3H)-thymidine were performed throughout the year and incorporation into pyloric caeca and into gonads was studied. Tritiated thymidine was found to be incorporated mainly in the coelomic lining of both organs. Cell divisions in the coelomic lining may be necessary for the growth of these organs, for the production of coelomocytes or, in the case of the pyloric caeca, for growth of the digestive epithelium. Proliferative activity of the digestive epithelium of the pyloric caeca was only observed in the median duct. It is hypothesized that new cells, arising from mitosis, grow from the median duct to the side lobes and differentiate into storage cells, for example. The existence of a mitosis-inducing or mitosis-stimulating substance is discussed. In the ovaries follicle cells were found to incorporate (methyl-3H)-thymidine; in the testis, proliferation of the germinal epithelium occurred simultaneously in all spermatogenic columns. First, the spermatogonia and then later the spermatocytes became labeled. Absorption of substances from the coelomic fluid is discussed.  相似文献   

6.
The application of simple sequence repeat (SSR) genotyping for the characterization of genetic variation in crop plants has been hindered by ready access to useful primer pairs and potentially limited conservation of the repeat sequences among related species. In this phase of work, we report on the identification and characterization of SSRs that are conserved in Brassica napus L. (rapeseed) and its putative progenitors, B. oleracea L. (cabbage, and related vegetable types) and B. rapa (vegetable and oil types). Approximately 140 clones from a size-fractionated genomic library of B. napus were sequenced, and primer pairs were designed for 21 dinucleotide SSRs. Seventeen primer pairs amplified products in the three species and, among these, 13 detected variation between and within species. Unlike findings on SSR information content in human, no relationship could be established between the number of tandem repeats within the target sequence and heterozygosity. All primer pairs have been designed to work under identical amplification conditions; therefore, single-reaction, multiplex polymerase chain reaction (PCR) with these SSRs is possible. Once moderate numbers of primer pairs are accessible to the user community, SSR genotyping may provide a useful method for the characterization, conservation, and utilization of agricultural crop diversity.  相似文献   

7.
A new species of Allopodocotyle Pritchard, 1966 is described from the intestine and pyloric caeca of Parequula melbournensis (Gerreidae) caught from the waters off South and Western Australia. The new species is distinguished from other species by its larger eggs, broader form, pre-bifurcal genital pore and a number of other measurable features that are discussed. Of the species that share morphological similarities with Allopodocotyle skoliorchis n. sp., it is the only species known from a gerreid; all the other species are from serranids.  相似文献   

8.
Summary The name Deurithitrema gingae n. g., n. sp. is proposed for worms from the kidneys of one Crocodylus porosus from Darwin, Northern Territory, Australia. The following combination of characters distinguishes the new genus from all others: prepharynx very short; oesophagus absent; caeca reaching to posterior end of body; testes tandem in middle third of body, contiguous or amost so; cirrus-sac large, over-reaches ventral sucker, contains bipartite seminal vesicle, prostatic regions and ejaculatory duct with spines around its opening into genital atrium; genital pore immediately in front of ventral sucker; uterus coiled to posterior end of body; vitellaria lateral from ventral sucker to slightly behind testes; excretory vesicle small, receiving a single ventro-lateral duct from each side behind end of uterine loops. Deurithitrema belongs to the superfamily Plagiorchioidea Dollfus, 1930. It superficially resembles a number of genera, but its relationships within the superfamily are obscure.  相似文献   

9.
Prey species of the deepwater squid Moroteuthis ingens were examined for 37 large specimens captured in New Zealand waters. Caecum contents were predominantly less than 80% full and covered a range of digestion stages. The diet consisted of fish (at least seven species, of which four were myctophids) and squid. The most abundant prey was the myctophid Lampanyctodes hectoris, which was represented by 1323 otoliths from 22 caeca. The second most abundant prey was viperfish (Chauliodus sloani) and/or dragonfish (Stomias boa), represented by 537 otoliths from 17 caeca. Individual squid appeared to ingest surprisingly large numbers of fish (up to 100) during a single feeding period and could achieve feeding rates greater than 10% of their body weight per day. While some males appeared to ingest larger numbers of L. hectoris, females targeted significantly larger individuals of L. hectoris thereby ingesting a greater biomass of fish. Received: 31 July 1997 / Accepted: 15 January 1998  相似文献   

10.
Macrourimegatrema gadoma n. sp. (Digenea: Opecoelidae: Plagioporinae) is described from the pyloric caeca and intestine of the doublethread grenadier Gadomus arcuatus (Goode & Bean) (Macrouridae) collected from the northeastern Gulf of Mexico and off Venezuela. The new species differs from Macrourimegatrema brayi Blend, Dronen & Armstrong, 2004, the type and only species in the genus, in the distribution of the vitelline follicles and gonads, a larger body size, and the presence of highly-folded caeca with numerous outpocketings or pouches. It is suggested that species of Macrourimegatrema Blend, Dronen & Armstrong, 2004 probably infect their piscine hosts through the ingestion of a benthopelagic crustacean.  相似文献   

11.
The pyloric caeca of the starfish Asterias rubens were investigated histochemically during the reproductive cycle. The median duct and the side lobes reacted differently. The median duct reacted positively for acid phosphatases and glucose-6-phosphate dehydrogenase, whereas the side lobes reacted positively for alkaline phosphatases, neutral lipids, and fatty acids. In the transition zone between the median duct and the side lobes, the reaction for alkaline phosphatases and neutral lipids increased toward the side lobes. The function of the enzymes and the histochemical results are discussed in relation to the function of the pyloric caeca and to the reproductive cycle.  相似文献   

12.
A new cucullanid, Dichelyne bonacii n. sp., is described from the intestine of the grey snapper Lutjanus griseus and the stomach of the black grouper Mycteroperca bonaci off the coast of Yucatán. The absence of a ventral precloacal sucker and the presence of 11 pairs of caudal papillae in males allocate it to the subgenus Dichelyne. It differs from its congeners in body dimensions and by having two almost equal spicules (left 712-950 and right 722-945m), two intestinal caeca and in the position of the deirids and excretory pore. Apparently, L. griseus acts as definitive host of this species, whereas M. bonaci may be considered as a postcyclic host. This new species represents the first record of a nematode of the subgenus Dichelyne in marine fishes of Mexico.  相似文献   

13.
Les auteurs décrivent et figurent Longiductotrema scandolensis, un trématode parasite du tube digestif de Larus cachinnans michaellis Naumann (Aves, Laridae) originaire de l'ile de Corse (France). Ce Microphallidé se distingue de L. floridensis décrit en Amérique du Nord et seule espèce du genre, par une taille corporelle plus grande, des caeca plus allongés, un canal éjaculateur d'anatomie différente et des follicules vitellins plus nombreux. Un synopsis des dix huit genres composant la sous-famille des Maritrematinae est proposé. La diversité et la banalité des caractéristiques anatomo-morphologiques de ces genres rendent difficile le choix des critères qui permettraient leur répartition en tribus naturelles aisément définies.The authors describe and illustrate Longiductotrema scandolensis, a digenean parasite of the digestive tract of Larus cachinnans michaellis Naumann (Aves, Laridae) from Corsica (France). This microphallid is different from the North American species L. floridensis, the only other species of this genus, in several characters: a greater body size, longer caeca, an ejaculatory duct with a different anatomy, and more numerous vitelline follicles. A synopsis is given of the eighteen genera of the subfamily Maritrematinae. The diverse but banal morphological characters of these genera make it difficult to find criteria for partitioning the subfamily into easily defined natural tribes.  相似文献   

14.
The generic diagnosis of Parancylodiscoides Caballero y C. & Bravo-Hollis, 1961 (Monogenoidea: Dactylogyridae), with three valid species, was amended to include dactylogyrids having: a haptor with dorsal and ventral anchor/bar complexes, 14 hooks (seven pairs) and four reservoirs (two pairs); a dorsal bar with bifurcate ends; hooks with protruding, blunt and slightly depressed thumbs and undilated shanks; a dextroventral vaginal aperture leading to an elongate and oblique vaginal vestibule; a germarium dextral to the testis; a vas deferens looping the left intestinal caecum; a copulatory complex lacking an accessory piece; and two intestinal caeca lacking diverticula and united posterior to the gonads. Parancylodiscoides is most similar to Sundatrema Lim & Gibson, 2009, from which it differs only by the position of the vaginal aperture (sinistroventral in Sundatrema spp.) and by lacking a sucker-like genital pore. New information concerning the number and distribution of haptoral hooks, the relative positions of the gonads and the course of the vas deferens was provided for the type-species, P. chaetodipteri Caballero y C. & Bravo-Hollis, 1961. Parancylodiscoides longiphallus (MacCallum, 1915) Lim & Gibson, 2009 was redescribed based on specimens collected from the Atlantic spadefish Chaetodipterus faber from the Gulf of Mexico off Mississippi and Guaratuba Bay, Paraná, Brazil; its occurrence on the Atlantic spadefish from the Gulf of Mexico, Guaratuba Bay and off Puerto Rico represented new geographical records for this helminth. Parancylodiscoides caballerobravorum Cezar, Luque & Amato, 1999 was considered a junior subjective synonym of P. longiphallus. The monotypic Isohaliotrema Young, 1968 was placed in synonymy with Parancylodiscoides and its type-species, I. platacis Young, 1968, transferred to Parancylodiscoides as Parancylodiscoides platacis (Young, 1968) n. comb.  相似文献   

15.
The first species of the genus Helobdella in Australia is recorded from Victoria. Helobdella papillornata has all of the diagnostic features of the genus including: triannulate segments, one pair of eyes on somite II, diffuse salivary glands, five crop caeca, one annulus between the gonopores and one annulus between the anus and the caudal sucker. It is characterised by a subterminal mouth, lobed gastric caeca, five to seven darkly pigmented papillae per somite on the dorsal surface, 14 brown dorsal stripes, five pairs of compact testisacs and a resting length of 15 mm and a maximum extended length of 40 mm. Individuals lay between 20 and 50 eggs attached directly to the ventral surface of the parent. At 20 °C the eggs hatch after 2 weeks and the young immediately reattach to the parent for a further 2 to 4 weeks, during which time the attached young feed on snails captured by the parent. After leaving the parent, young forage on their own or in small groups of three or more until they reach reproductive maturity. Individuals become reproductively mature, producing eggs and young, 3 to 4 months after hatching.  相似文献   

16.
The genus Dioscorea is widely distributed in tropical and subtropical regions, and is economically important in terms of food supply and pharmaceutical applications. However, DNA barcodes are relatively unsuccessful in discriminating between Dioscorea species, with the highest discrimination rate (23.26%) derived from matK sequences. In this study, we compared genic and intergenic regions of three Dioscorea chloroplast genomes and found that the density of SNPs and indels in intergenic sites was about twice and seven times higher than that of SNPs and indels in the genic regions, respectively. A total of 52 primer pairs covering highly variable regions were designed and seven pairs of primers had 80%–100% PCR success rate. PCR amplicons of 73 Dioscorea individuals and assembled sequences of 47 Dioscorea SRAs were used for estimating intraspecific and interspecific divergence for the seven loci: The rpoB‐trnC locus had the highest interspecific divergence. Automatic barcoding gap discovery (ABGD), Poisson tree processes (PTP), and generalized mixed Yule coalescence (GMYC) analysis were applied for species delimitation based on the seven loci and successfully identified the majority of species, except for species in the Enantiophyllum section. Phylogenetic analysis of 51 Dioscorea individuals (28 species) showed that most individuals belonging to the same species tended to cluster in the same group. Our results suggest that the variable loci derived from comparative analysis of plastid genome sequences could be good DNA barcode candidates for taxonomic analysis and species delimitation.  相似文献   

17.
Summary The biochemical composition of the pyloric caeca of femaleAsterias rubens was studied during the annual reproductive cycle. The amounts of nucleic acids, DNA and RNA were measured in addition to the amounts of lipids, glycogen, other reducing carbohydrates, free amino acids and proteins.A positive correlation of the pyloric caeca index to the biochemical constituents at the cellular level was established. The total DNA content of the pyloric caeca was found to increase with the pyloric caeca index.The relation of the biochemical composition of the pyloric caeca to the size changes of the organ is discussed. The hypothesis that the changes in size of the organ are due to changes both in the number and size of the cells is confirmed. The biochemical composition of the pyloric caeca and its relation to the reproductive cycle is discussed.Abbreviations GI gonad index - CPI pyloric caeca index  相似文献   

18.
D. Bunke 《Zoomorphology》1994,114(4):247-258
Summary The excretory system of Aeolosoma bengalense has been examined by light and electron microscopy. The system consists of seven serially arranged paris of metanephridia and six pairs of podocytes (referring to the first zoid of an animal chain). The podocytes surround blood spaces of the alimentary canal forming dorsoventrally running loops that emerge on both sides of it. The two elements of the system have a correlative position, each podocyte extending in close proximity to the funnel of a metanephridium. Only in the region of the first metanephridia are podocytes lacking. The nephrostome of the metanephridia consists of two cells, an inner one, the terminal duct cell, and an outer one enwrapping it, called the mantle cell. Nephrostomal cilia that extend into the coelomic space arise exclusively from the rim of the mantle cell whereas those of the terminal duct cell arranged on its luminal surface protrude into the canal forming a flame. The nephridial canal is ciliated throughout and is either intra- or extracellular. Its initial loops aggregate to form a compact organ, the nephridial body. The middle part of the duct constitutes a loop that ascends at each side of the alimentary canal where it is in intimate contact with its blood spaces. Ultrastructural features of the duct cells suggest a reabsorptive function in two regions, the nephridial body and the uppermost part of the loop. The terminal part of the duct passes through the nephridial body and opens ventrolaterally. Generally, the transverse vascular loops at the gut consist of one podocyte each. In the oesophageal region, where only one pair of podocytes is present, the loops connect the dorsal with the ventral longitudinal vessel. Three pairs of podocytes are present in the dilated region of the intestine emerging from its lateral wall and joining the median ventral vessel or blood spaces near by. In the hind gut, where two pairs of podocytes occur, the loops arise from the dorsolateral part and enter directly the ventral vessel. Cytological features of podocytes resemble those of other animals. The results are discussed on the basis of current theories on the function and the phylogenetic significance of excretory systems in the Annelida.Abbreviations bl basal lamina - bs blood space - bv blood vessel - cf ciliary flame - ci cilia - co connection of the vascular loop with the intestinal blood space - cu cuticle - db dense body - dc duct cell - di dictyosome - za zonula adhearens - dv dorsal vessel - ecb epicuticular body - ev endocytotic vesicle - ic intestinal cell - ici inner cilia - iv intestinal vessel - lm longitudinal muscle - mc mantle cell - mg midgut - mi mitochondrion - mv microvilli - nu nucleus - oci outer cilia - oe oesophagus - pc podocyte - pe pedicel - pel primary elongation of the podocyte - sm slit membrane - tc terminal duct cell - ve vesicle with heterogeneous contents - vv ventral vessel  相似文献   

19.
Thirteen seed samples of lentil (Lens esculenta) were incubated on agar plate and moist filter papers (Moist Chambers) at 28 ± 2 °C for determination of the incidence of seed-borne fungi. Aflatoxins content of the seeds was measured using the bright greenish-yellow fluorescence test (BGYF) and thin-layer chromatography (TLC). Sixty-nine species and seven varieties, which belong to 24 genera of fungi, were isolated from this crop. Of these fungi, 51 species and two varieties are considered new for this crop, whereas seven genera and 13 species are new to the mycoflora of the Sudan. The genus Aspergillus (13 species and 6 varieties) which comprising 44% of the total colony count was the most prevalent genus followed by Rhizopus (2 species, 19%), Penicillium (6 species) and Fusarium (8 species) (12%), Chaetomium (3 species) and Cladosporium (5 species) (6%), where the 18 genera (1–4 species) showed very low level of incidence (19%). Of the possible pathogens of lentil plants, F. oxysporum the main cause of vascular wilt was recovered from seeds of this crop. Thin layer chromatographic analysis of chloroform extracts of 13 seed samples showed that only one samples was naturally contaminated with aflatoxins B1, B2, G1 and G2 (14.3 μg/kg). This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

20.
Calicotyle japonica n. sp., collected from the uterus, rectal gland, archinephric duct and cloaca of the shortspine spurdog Squalus mitsukurii Jordan & Snyder (Squaliformes) off the Pacific coast of Japan, is described. The new species can be distinguished from C. inermis Woolcock, 1936 by the shape of the male copulatory organ; in C. japonica this is directed anteriorly, is sharply bent in the middle and then increases in width toward the tip, whereas it is long, coiled and uniform in width throughout its entire length in C. inermis. Furthermore, the intestinal caeca have many irregular diverticula on both sides and the vaginal apertures are at the level of the common genital pore in Cjaponica, whereas in C. inermis the intestine is smooth and the vaginae open at the level of the o?type. A phylogeny constructed using LSU rDNA data indicates that the new species is grouped with other Calicotyle species; based on this, Gymnocalicotyle Nybelin, 1941 is synonymised with Calicotyle Diesing, 1850. Calicotyle is divided into two major clades, with the new species being grouped with Calicotyle species infecting sharks and the second clade consisting of Calicotyle spp. infecting rays. This suggests that the loss of the hamuli in Cjaponica and C. inermis, both parasites of sharks, is a comparatively recent event in the evolution of the genus.  相似文献   

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