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1.
A new species of Allassogonoporus Olivier, 1938, from a naturally infected specimen of Dromiciops gliroides, is described. Adults of A. dromiciops n. sp. were recovered from the small intestine. This new species can be distinguished from all other species of the genus by having: the largest body and eggs, a lobed testes and ovary, a Y-shaped excretory vesicle and vitelline follicles beginning at the level of the posterior margin of the oral sucker. This is the first record of a species of Allassogonoporus in South America and the first record of a digenean parasitising D. gliroides.  相似文献   

2.
Atactorhynchus duranguensisn. sp. (Acanthocephala: Atactorhynchinae) is described from the intestine of Cyprinodon meeki Miller, an endemic freshwater fish from a far-inland locality of Mexico. Diagnostic features include: body small, stout, ventrally curved; small cylindrical proboscis armed with 16 alternating vertical rows of four or five hooks; anterior two or three hooks conspicuous, stout and larger than other hooks, and have large, rod-shaped roots with a markedly and abruptly enlarged base; three posterior hooks of each row are smaller and rootless; single-walled proboscis receptacle; lemnisci equal in length, elongate and robust; and cement gland syncytial, larger than testis. The new species is smaller than A. verecundus Chandler, 1935, the only previously described species in the genus. The shape of the proboscis of the new species is strikingly different from that of A. verecundus, which is widest at the apex. Likewise, the greatest width of the trunk of the new species is in about the middle, differing from that of A. verecundus where the trunk is widest posteriorly. The new species also can be distinguished from A. verecundus because of its much smaller hook lengths and slightly smaller proboscis. In addition, the proportion of large apical proboscis hooks in relation to the small basal hooks is different: the basal hooks of A. verecundus are about half the size of the anterior hooks and but only about a quarter of the size in A. duranguensis. Unlike A. verecundus, the base of the roots are markedly and abruptly enlarged in the new species. Finally, the eggs of the new species are smaller (23–27 × 8–10 m) than those of A. verecundus (27–30 × 12–13 m).  相似文献   

3.
Neolebouria blatta n. sp. is described from Pristipomoides argyrogrammicus (Valenciennes) and Etelis carbunculus Cuvier in waters off New Caledonia. It differs from all other species of Neolebouria Gibson, 1976 but one, N. georgenascimentoi Bray, 2002, in the extension of the cirrus-sac to the ovary or nearly so. It differs from N. georgenascimentoi in its continuous, rather than interrupted, vitelline distribution. N. blatta belongs to a small group of similar Neolebouria species reported in deep-water lutjanids, which includes N. longisacculus (Yamaguti, 1970) n. comb., N. rooseveltiae (Yamaguti, 1970) n. comb. and N. ulaula (Yamaguti, 1970).  相似文献   

4.
5.
Aploparaksis demshini n. sp. is described from a woodcock Scolopax rusticola L. from different parts of the Palaearctic (Lithuania, Karelia, the Urals, Primorskiy Kray). It differs from the most similar species A. belopolskajae Bondarenko, 1988, a parasite of snipes Gallinago spp., in the form and length of the rostellar hooks and the smaller cirrus, and from two other similar species, A. clavata Spasskaya, 1966 and A. schilleri Webster, 1955, by having an embryophore with polar thickenings and a spindle-shaped cirrus. The life-cycle of the parasite was studied under experimental conditions. The metacestodes were commonly located under the chlorogogenous tissue of the intestine of the earthworms Eisenia foetida(Savigny), Dendrobaena octaedra (Savigny) and E. nordenskioldi(Eisen), and in the wall of the intestine of the enchytraeid Briodrilus arcticus(Bell). The metacestodes exhibit a pattern of postembryonal development typical for the cysticercoid modification termed an ovoid diplocyst.  相似文献   

6.
In fish, bacterial pathogens can enter the host by one or more of three different routes: (a) skin, (b) gills and (c) gastrointestinal tract. Bacteria can cross the gastrointestinal lining in three different ways. In undamaged tissue, bacteria can translocate by transcellular or paracellular routes. Alternatively, bacteria can damage the intestinal lining with extracellular enzymes or toxins before entering. Using an in vitro (Ussing chamber) model, this paper describes intestinal cell damage in Atlantic salmon (Salmo salar L.) caused by the fish pathogen Aeromonas salmonicida ssp. salmonicida, the causative agent of furunculosis. The in vitro method clearly demonstrated substantial detachment of enterocytes from anterior region of the intestine (foregut) upon exposure to the pathogen. In the hindgut (posterior part of the intestine), little detachment was observed but cellular damage involved microvilli, desmosomes and tight junctions. Based on these findings, we suggest that A. salmonicida may obtain entry to the fish by seriously damaging the intestinal lining. Translocation of bacteria through the foregut (rather than the hindgut) is a more likely infection route for A. salmonicida infections in Atlantic salmon.Financial support from the Commission of the European Communities, quality of Life and Management of Living Resources programme, project Q5RT-2000-31656 Gastrointestinal Functions and Food Intake Regulation in Salmonids: Impact of Dietary vegetable Lipids (GUTINTEGRITY) and from Magnus Bergvalls Stiftelse for KS, is acknowledged.This work does not represent the opinion of the European Community, which is thus not responsible for any use of the data presented.  相似文献   

7.
8.
Spicocleidus n. g. is proposed for S. namae n. sp., a new monogenean collected from the gills of an ambassid, Chanda nama (Ham.), in the River Sai near Lucknow, Uttar Pradesh, India. The new genus is characterised by a pair of modified dorsal anchors (spikes), the absence of a dorsal bar, alate lateral expansion of the anterior haptor and the post-ovarian position of the testis.  相似文献   

9.
Two species of nematodes, Angiostoma coloaense n. sp. and Aulacnema monodelphis n. g., n. sp. (Angiostomatidae: Rhabditida) are described from terrestrial molluscs of Vietnam. Both species are characterised by a long bowl-shaped buccal cavity and typically angiostomatid male bursal alae, spicules and gubernaculum. The new genus, Aulacnema n. g., is erected for the first reported monodelphic angiostomatid. Angiostoma coloaense n. sp. can be distinguished from other species of Angiostoma Dujardin, 1845 by having a buccal cavity length greater than its width and the absence of tail spikes on both males and females.  相似文献   

10.
The morphological variation of recently described species (also the older taxa) of Zamia distributed within southeastern Mexico that have wide, coriaceous leaflets is analyzed. The complex is designated as the Z. katzeriana species complex in reference to an historic collection of this name, which is also the earliest named species in the complex. The complex consists of Z. cremnophila, Z. lacandona, Z. splendens and Z. purpurea. During the 1990’s, Z. splendens was separately synonymized under Z. katzeriana and Z. verschaffeltii, both collected in Mexico by German collectors during the 18th century, but the precise locality is unknown. Information concerning the incomplete holotype of Z. verschaffeltii is particularly ambiguous, and the possible type locality suggested by Schuster, Socorro, is imprecise, thus generating taxonomic confusion. Morphometric characterization and discriminant analysis of the contemporary and historic collections (i.e., Z. katzeriana and Z. verschaffeltii) included all the known populations (11) and individuals (115) of the complex throughout its range. The results show that Z. verschaffeltii is not morphometrically related to any of the species in the complex and that Z. splendens should be considered a synonym of Z. katzeriana.
Resumen  En este artículo se caracteriza la variación morfológica de las especies de un complejo de Zamia, que presentan folíolos anchos y coriáceos con distribución en el sureste de México, la mayoría de reciente descripción. El complejo es denominado Z. katzeriana, por una colección histórica de este nombre, y consiste de Z. cremnophila, Z. lacandona, Z. splendens y Z. purpurea. Zamia splendens fue sinonimizada separadamente bajo dos colecciones históricas Z. katzeriana y Z. verschaffeltii, de las cuales se desconoce con exactitud su lugar de procedencia, excepto que fueron colectadas en México por botánicos alemanes del siglo XVIII. La información, en especial sobre el holotipo incompleto de Z. verschaffeltii es muy ambigua y la posible localidad tipo mencionada por Schuster, Socorro, es imprecisa, lo cual ha generado confusiones taxonómicas. La caracterización de la variación morfométrica incluyó a todas las poblaciones (11) e individuos (115) conocidas actualmente para el complejo en todo su rango de distribución en México. El análisis discriminante incluyendo a las colecciones históricas, determina que Z. verschaffeltii no está relacionado morfométricamente con ninguna especie del complejo y Z. katzeriana está estrechamente correlacionada con Z. splendens.
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11.
Clestobothrium gibsoni n. sp. is described from the intestine of the bullseye grenadier Bathygadus macrops (Macrouridae) collected in the northeastern Gulf of Mexico. The new species can be distinguished from both C. crassiceps (Rudolphi, 1819), the type-species of the genus, and C. neglectum (Lönnberg, 1893), the second species in the genus, by its unique ovary, which is transversely elongate and tapered on both ends rather than being U-or H-shaped, and by having more testes (60-65 vs 40-50 and 35-45 per proglottid). The new species is also compared to Bothriocephalus acheilognathi Yamaguti, 1934 and B. kivuensis Baer & Fain, 1954, two species with similar scoleces which have previously been assigned to Clestobothrium . The generic diagnosis of Clestobothrium is amended to include species with either anoperculate or operculate eggs. This is the first report of an adult tapeworm from a species of Bathygadus , and the first report of a species of Clestobothrium Lühe, 1899 (Bothriocephalidae) from the Gulf of Mexico.  相似文献   

12.
A new trematode genus, Grammatorcynicola n. g. (Bucephalidae: Dolichoenterinae), and two new species, G. brayi n. sp. and G. nolani n. sp. from the intestines of the scombrids, Grammatorcynus bicarinatus and Gr. bilineatus respectively, are reported from the Great Barrier Reef, Australia. Grammatorcynicola n. g. is placed in the Dolichoenterinae, as the pharynx is in the anterior quarter of the body, the caecum is tube-like and extends to the posterior quarter of the body, the cirrus-sac is small relative to the size of the worm when compared with other bucephalids and the pars prostatica is curved. Grammatorcynicola n. g. differs from other dolichoenterine genera in having a simple sucker-like rhynchus, the ovary anterior to the testes and by not having a particularly thick cirrus-sac wall.  相似文献   

13.
14.
Ogataea parapolymorpha sp. n. (NRRL YB-1982, CBS 12304, type strain), the ascosporic state of Candida parapolymorpha, is described. The species appears homothallic, assimilates methanol as is typical of most Ogataea species and forms hat-shaped ascospores in asci that become deliquescent. O. parapolymorpha is closely related to Ogataea angusta and Ogataea polymorpha. The three species can be resolved from gene sequence analyses but are unresolved from fermentation and growth reactions that are typically used for yeast identification. On the basis of multiple isolates, O. angusta is known only from California, USA, in association with Drosophila and Aulacigaster flies, O. parapolymorpha is predominantly associated with insect frass from trees in the eastern USA but O. polymorpha has been isolated from various substrates in the USA, Brazil, Spain and Costa Rica.  相似文献   

15.
Malalophus jensenae n. g., n. sp. is described from the gills of the ornate eagle ray Aetomylaeus vespertilio (Bleeker) collected off the eastern coast of the Gulf of Carpentaria, northern Queensland. The new genus is similar to Heliocotyle Neifar, Euzet & Ben Hassine, 1999, with which it shares a haptor bearing seven peripheral loculi and a single dorsal haptoral accessory structure. M. jensenae can be distinguished from species of Heliocotyle by the presence of numerous sclerotised sinuous ridges covering the ventral surfaces of the peripheral loculi of the haptor. It also lacks pseudosepta which are present on the haptor of Heliocotyle species. This is the first published record of a monogenean from an elasmobranch in the Gulf of Carpentaria, Australia.  相似文献   

16.
Inter- and intracellular cysts from a presumed single species, Myxobolus procerus (Kudo, 1934), parasitising the trout-perch Percopsis omiscomaycus were compared with respect to their spore morphology and small subunit 18S ribosomal DNA. The two cyst types have similar pyriform spores and comparable ranges in spore length and width, size of the polar capsules and number of filament coils. However, fixed spores of the intracellular cysts are significantly shorter (p < 0.05) in mean length than those from intercellular cysts, giving them a broader appearance. Comparing 991 base pairs of 18S rDNA revealed a 20 bp difference between the two cyst types (97.9% similarity), 10 due to base substitutions and 10 due to the presence or absence of a base. The described morphological differences and consistent 2.1% difference in the 18S rDNA reveal that the intracellular form is a separate species, which is described herein as Myxobolus intramusculi n. sp. M. intramusculi n. sp. and M. procerus may be sister species and it is suggested that the two species arose through sympatric speciation involving a switch in site specificity within a single host species.  相似文献   

17.
18.
We have investigated the floral ontogeny of Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis (of the eucalypt group, Myrtaceae) using scanning electron microscopy and light microscopy. Several critical characters for establishing relationships between these genera and to the eucalypts have been determined. The absence of compound petaline primordia in Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis excludes these taxa from the eucalypt clade. Post-anthesis circumscissile abscission of the hypanthium above the ovary in Stockwellia, Eucalyptopsis and Allosyncarpia is evidence that these three taxa form a monophyletic group; undifferentiated perianth parts and elongated fusiform buds are characters that unite Stockwellia and Eucalyptopsis as sister taxa. No floral characters clearly associate Arillastrum with either the eucalypt clade or the clade of Stockwellia, Eucalyptopsis and Allosyncarpia.We gratefully acknowledge Clyde Dunlop and Bob Harwood (Northern Territory Herbarium) for collecting specimens of Allosyncarpia, and Bruce Gray (Atherton) for collecting specimens of Stockwellia. The Australian National Herbarium (CANB) kindly lent herbarium specimens of Eucalyptopsis for examination. This research was supported by a University of Melbourne Research Development Grant to Andrew Drinnan.  相似文献   

19.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.  相似文献   

20.
New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.  相似文献   

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