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1.
David G.  Cook 《Journal of Zoology》1968,156(3):273-289
Stephenson (1930) recognized 15 genera, and Hrabě (1936 to 1963) has distinguished 17 genera of Lumbriculidae, a family of freshwater Oligochaeta. On the basis of the form and arrangements of the parts of the genital system, a scheme is suggested in which 12 genera of Lumbriculidae are recognized. These genera are defined and a key erected for their identification. Reasons for removing Dorydrilus Piguet, 1913 from the Lumbriculidae are presented and the family Dorydrilidae fam. n. is defined to accommodate the genus.  相似文献   

2.
Phylogenetic relationships within the class Clitellata were examined using partial nucleotide sequences of the nuclear 18S ribosomal RNA gene. In the analysis, the already determined sequences for the individual species representing the class members Hirudinea, Acanthobdellida, Branchiobdellida, and Oligochaeta were included. Furthermore, newly determined sequences of the thirteen representatives of the family Lumbriculidae, including 12 Baikalian endemic species, were analyzed. The hypothesis on the close relatedness of these four groups of Clitellata was supported. Leeches, branchiobdellids, and lumbriculids form three independent parallel branches of evolution. These results were consistent with the hypothesis on the role of the family Lumbriculidae as a connecting link, or the transition form between the parasitic and free-living groups of Clitellata. At the same time, these data refute the suggestion that Lumbriculidae could be the ancestral lineage of other Oligochaeta. Moreover, polymorphic group of Baikalian lumbriculids clustered independently from the other representatives of the family, pointing to the uniqueness of the Baikalian fauna of oligochaetes, which was formed within relatively closed system of this ancient lake.  相似文献   

3.
The rudimentary atria, and the posterior sperm funnels and sperm ducts, which occur in some species of the Lumbriculidae, are discussed. It is shown that the posterior location of funnels and sperm ducts is the result of a forward shift of the atria, which refutes Stephenson's supposition that the Lumbriculidae is the most archaic family of the present-day Oligochaeta.  相似文献   

4.
Phylogenetic relationships within the class Clitellata were examined using nucleotide sequences of nuclear 18S ribosomal RNA gene fragments. In the analysis, the already determined sequences for the individual species representing the class members Hirudinea, Acanthobdellida, Branchiobdellida, and Oligochaeta were included. Furthermore, newly determined sequences of the thirteen representatives of the family Lumbriculidae. including 12 Baikalian endemic species, were analyzed. The hypothesis on the close relatedness of these four groups of Clitellata was supported. Leeches, branchiobdellidans, and lumbriculides form three independent parallel branches of evolution. These results were consistent with the hypothesis on the role of the family Lumbriculidae as a connecting link, or the transition form between the parasitic and free-living groups of Clitellata. At the same time, these data refute the suggestion that Lumbriculidae could be the ancestral lineage of other Oligochaeta. Moreover, polymorphic group of Baikalian lumbriculides clustered independently from the other representatives of the family, pointing to the uniqueness of the Baikalian fauna of oligochaetes, which was formed within relatively closed system of this ancient lake.  相似文献   

5.
Abstract

The oligochaete family Lumbriculidae is well represented in the Northern Hemisphere, but for the Southern Hemisphere only Lumbriculus variegatus (Müller) is recorded, from Africa, Australia, and New Zealand; no species are known from South America (Brinkhurst & Jamieson 1971). According to Brinkhurst (1971), L. variegatus may be a recent introduction to New Zealand, where it is now widely distributed in a range of inland waters.  相似文献   

6.
Comments on the evolution of the Annelida   总被引:6,自引:4,他引:2  
The structure of the male ducts and their relative positions are significant indicators of the fact that the Lumbriculidae do not represent the stem forms of the Oligochaeta, confirming the recently expressed opinion of Hrab (1983). However, the same arguments provide the basis for the separation of Dorydrilus in the family Dorydrilidae.  相似文献   

7.
Studies on the Lumbriculidae (Oligochaeta) in Britain   总被引:2,自引:0,他引:2  
Seven species of Lumbriculidae, a family of fresh water Oligochaeta, found in Britain are described and a key is erected for their identification. Two species of Trichodrilus , separated by Beddard are redescribed, resulting in a new synonymy. Trichodrilus Hrabêi sp. n. from Denbighshire is denned. Dorydrilus michaeheni is recorded for the first time from Great Britain.  相似文献   

8.
18S rDNA phylogeny of Clitellata (Annelida)   总被引:8,自引:0,他引:8  
The phylogeny of Clitellata was analysed using 18S rDNA sequences of a selection of species representing Hirudinida, Acanthobdellida, Branchiobdellida and 10 oligochaetous families. Eleven new 18S sequences of Capilloventridae (one), Haplotaxidae (one), Propappidae (one), Enchytraeidae (two), Lumbricidae (one), Almidae (one), Megascolecidae (two), Lumbriculidae (one), and Phreodrilidae (one) are reported and aligned together with corresponding sequences of 28 previously studied clitellate taxa. Twelve polychaete species were used as an outgroup. The analysis supports an earlier hypothesis based on morphological features that Capilloventridae represents a basal clade of Clitellata; in the 18S tree it shows a sister-group relationship to all other clitellates. The remaining clitellate taxa form a basal dichotomy, one clade containing Tubificidae (including the former 'Naididae'), Phreodrilidae, Haplotaxidae, and Propappidae, the other clade with two subgroups: (1) Lumbriculidae together with all leech-like taxa (Acanthobdellida, Branchiobdellida and Hirudinida), and (2) Enchytraeidae together with a monophyletic group of all earthworms included in the study (Lumbricidae, Almidae and Megascolecidae). These earthworms are members of the taxon Crassiclitellata, the monophyly of which is thus supported by the data. The tree also shows support for the hypothesis that the first clitellates were aquatic. The position of the single species representing Haplotaxidae is not as basal as could have been expected from earlier morphology-based conclusions about the ancestral status of this family. However, if Haplotaxidae is indeed a paraphyletic assemblage of relict taxa, a higher number of representatives will be needed to resolve its exact relationships with the other clitellates.  相似文献   

9.
10.
Hundreds of active and dormant geothermal vents have been located on the floor of Yellowstone Lake, although characterization of the associated biology (macro or micro) has been extremely limited. Herein, we describe an aquatic moss (Fontinalis) colony closely associated with vent emissions that considerably exceeded known temperature maxima for this plant. Vent waters were supersaturated with CO2, likely accommodating a CO2 compensation point that would be expected to be quite elevated under these conditions. The moss was colonized by metazoa, including the crustaceans Hyalella and Gammarus, a segmented worm in the Lumbriculidae family, and a flatworm specimen tentatively identified as Polycelis. The presence of these invertebrates suggest a highly localized food chain that derives from the presence of geothermal inputs and thus is analogous to the deep marine vents that support significant biodiversity.  相似文献   

11.
Characteristics common to a cytokine family spanning five orders of insects   总被引:1,自引:0,他引:1  
Growth-blocking peptide (GBP) is a member of an insect cytokine family with diverse functions including growth and immunity controls. Members of this cytokine family have been reported in 15 species of Lepidoptera, and we have recently identified GBP-like peptides in Diptera such as Lucilia cuprina and Drosophila melanogaster, indicating that this peptide family is not specific to Lepidoptera. In order to extend our knowledge of this peptide family, we purified the same family peptide from one of the tenebrionids, Zophobas atratus,1 isolated its cDNA, and sequenced it. The Z. atratus GBP sequence together with reported sequence data of peptides from the same family enabled us to perform BLAST searches against EST and genome databases of several insect species including Coleoptera, Diptera, Hymenoptera, and Hemiptera and identify homologous peptide genes. Here we report conserved structural features in these sequence data. They consist of 19–30 amino acid residues encoded at the C terminus of a 73-152 amino acid precursor and contain the motif C-x(2)-G-x(4,6)-G-x(1,2)-C-[KR], which shares a certain similarity with the motif in the mammalian EGF peptide family. These data indicate that these small cytokines belonging to one family are present in at least five insect orders.  相似文献   

12.
The synthesis of 2-(5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimidin-4-yl)hydrazone-derivatives (BTPs) and their in vitro evaluation against Trypanosoma cruzi trypomastigotes, Mycobacterium tuberculosis, Leishmania amazonensis axenic amastigotes, and six human cancer cell lines is described. The in vivo activity of the most active and least toxic compounds against T. cruzi and L. amazonensis was also studied. BTPs constitute a new family of drug leads with potential activity against infectious diseases. Due to their drug-like properties, this series of compounds can potentially serve as templates for future drug-optimization and drug-development efforts for use as therapeutic agents in developing countries.  相似文献   

13.
14.
A 573-bp region of the mitochondrial gene cytochrome c oxidase subunit I (COI) of two species of Inanidrilus Erséus and four species of Olavius Erséus (Phallodrilinae, Tubificidae) is used in a parsimony analysis together with a selection of 35 other annelids (including members of Polychaeta, Pogonophora, Aphanoneura, and the clitellate taxa Tubificidae, Enchytraeidae, Naididae, Lumbriculidae, Haplotaxidae, Lumbricidae, Criodrilidae, Branchiobdellida and Hirudinea), and with two molluscs as outgroups. The data support the monophyly of the Olavius and Inanidrilus group, with a monophyletic Inanidrilus . However, parsimony jackknife analyses show that most of the other groups are unsupported by the data set, thus revealing a large amount of homoplasy in the selected gene region. Practically no information is given of within/between family relationships except for a few, closely related species. This suggests that the analysed COI region is not useful, when used alone, for inferring higher level relationships among the annelids.  相似文献   

15.

Background

Highly conserved intracellular proteins from Leishmania have been described as antigens in natural and experimental infected mammals. The present study aimed to evaluate the antigenicity and prophylactic properties of the Leishmania infantum Poly (A) binding proteins (LiPABPs).

Methodology/Principal Findings

Three different members of the LiPABP family have been described. Recombinant tools based on these proteins were constructed: recombinant proteins and DNA vaccines. The three recombinant proteins were employed for coating ELISA plates. Sera from human and canine patients of visceral leishmaniasis and human patients of mucosal leishmaniasis recognized the three LiPABPs. In addition, the protective efficacy of a DNA vaccine based on the combination of the three Leishmania PABPs has been tested in a model of progressive murine leishmaniasis: BALB/c mice infected with Leishmania major. The induction of a Th1-like response against the LiPABP family by genetic vaccination was able to down-regulate the IL-10 predominant responses elicited by parasite LiPABPs after infection in this murine model. This modulation resulted in a partial protection against L. major infection. LiPABP vaccinated mice showed a reduction on the pathology that was accompanied by a decrease in parasite burdens, in antibody titers against Leishmania antigens and in the IL-4 and IL-10 parasite-specific mediated responses in comparison to control mice groups immunized with saline or with the non-recombinant plasmid.

Conclusion/Significance

The results presented here demonstrate for the first time the prophylactic properties of a new family of Leishmania antigenic intracellular proteins, the LiPABPs. The redirection of the immune response elicited against the LiPABP family (from IL-10 towards IFN-γ mediated responses) by genetic vaccination was able to induce a partial protection against the development of the disease in a highly susceptible murine model of leishmaniasis.  相似文献   

16.
17.
ON THE PHYLOGENY AND HIGHER CLASSIFICATION OF THE OLIGOCHAETA   总被引:3,自引:0,他引:3  
Abstract— The 50 oligochaete taxa representing all families of “opisthoporous” oligochaetes (Aliuroididae, earthworms and aquatic “megadriles”) together with two representatives of the Haplotaxidac and three examples of “microdiles” were subjected to cladistic analysis using the PAUP program. Sixty-eight characters used in the analyses were derived from a comprehensive range of somatic and genital systems. The optimal result, in terms of maximal number of characters and taxa and of parsimony, produced two trees (consistency index 0.362) differing only in the placement of the monotypic clade for the family Lumbriculidae. From a line originating from the presumed octogonadial ancestor, the following branches were derived, in sequence from the basal to most derived (new taxa asterisked): subclass Randiellata* (order Randiellida*, Randiellidae); subclass Tubificata* (order Tubificida, Tubincidae, Naididae computed and others not computed); subclass Lumbriculata* (order Lumbriculida, Lumbriculidae); superorder Haplotaxidea* (order Haplotaxida, Haplotaxidae); order Moniligastrida (Moniligastridae); suborder Alluroidina (Aliuroididae and Syngenodrilidae); cohort Aquamegadrili* (with, in succession, superfamilice Sparganophiloidea, Sparganophilidae; Biwadriloidea, Biwadrilidac, and Almoidca—Lutodrilidac and Almidae, including Criodrilus); superfamily Eudriloidea*, superfamily Lumbricoidea and, as the adelphotaxon of the latter, the superfamily Megascolecoidea. Intermediate nodes were given the following names, with the adelpholaxon through to the Megascolecoidea, M, in parentheses: subclass Diplotesticulata (Haplotaxidea—M); superorder Metagynopohora* (Moniligastrida—M); order Opisthopora (Alluroidina M); suborder Crassiclitellata* (Aquamegadrili — M); cohort Terrimegadrili* (Ocnerodriloidea M); unnamed (Eudriloidea M); unnamed (Lumbricoidea and Megascolecoidea). Recognition of the Randiellata, which alone were added intuitively and not computed, and the position of the Lumbriculata, are tentative. Location of the Lumbricoidea as the adelphotaxon of a restricted Megascoecloidea is heuristic, but the alternative depiction of lumbricoids in some analyses, as the adelphotaxon of an ocnerodrilid-eudrilid-megascolecoid clade (the conventional Megascolecoidea s. lat.), is not conclusively dismissed.  相似文献   

18.
The enoyl acyl-carrier protein reductase (ENR) enzyme of the apicomplexan parasite family has been intensely studied for antiparasitic drug design for over a decade, with the most potent inhibitors targeting the NAD+ bound form of the enzyme. However, the higher affinity for the NADH co-factor over NAD+ and its availability in the natural environment makes the NADH complex form of ENR an attractive target. Herein, we have examined a benzimidazole family of inhibitors which target the NADH form of Francisella ENR, but despite good efficacy against Toxoplasma gondii, the IC50 for T. gondii ENR is poor, with no inhibitory activity at 1 μM. Moreover similar benzimidazole scaffolds are potent against fungi which lack the ENR enzyme and as such we believe that there may be significant off target effects for this family of inhibitors.  相似文献   

19.
The phylogeny of the Tubificidae, and of most of its subfamilies and some of its genera, is revisited, on the basis of sequences of 18S ribosomal DNA in a selection of species. Forty-six new 18S sequences of Naididae (6), Tubificidae (37), Phreodrilidae (1), Lumbriculidae (1), and Enchytraeidae (1) are reported and aligned together with corresponding sequences of 21 previously studied taxa. The 18S gene of Insulodrilus bifidus provides the first molecular evidence that phreodrilids are closely related to tubificids, corroborating previous conclusions based on morphology. The data further support the monophyletic status of Tubificidae, provided that the "Naididae" is regarded a part of this family; "naidids" may not even constitute a monophyletic group. It is thus suggested that the family name Naididae is formally suppressed as a junior synonym of the Tubificidae. The 18S gene also resolves a number of relationships within the tubificids. Among the subfamilies, Tubificinae is supported, Rhyacodrilinae and Phallodrilinae are revealed as nonmonophyletic, and Limnodriloidinae remains unresolved. Most tubificid genera tested for monophyly are corroborated by the data, only one (Tubifex) is refuted, and two (Tubificoides and Limnodriloides) are unresolved from other taxa. It is concluded that it will be valuable to expand the taxonomic sampling for 18S rDNA in clitellates, and in annelids in general, as this is likely to improve the resolution at many levels. However, it will be equally important to combine the annelid 18S data with other gene sequences and nonmolecular characters, to estimate the phylogeny of these common and diverse worms with greater precision.  相似文献   

20.
While investigating antimicrobial peptide diversity of Amolops loloensis, five novel antimicrobial peptides belonging to two families were identified from skin secretions of this frog. The first family including two members is esculentin-2-AL (esculentin-2-ALa and -ALb); the second family including three members is temporin-AL (temporin-ALd to -ALf). The family of esculentin-2-AL is composed of 37 amino acid residues (aa); the family of temporin-AL is composed of 16, 13 and 10 aa, respectively. All of these antimicrobial peptides showed antimicrobial activities against tested microorganisms. cDNAs encoding precursors of esculentin-2-ALs and temporin-ALs were cloned from the skin cDNA library of A. loloensis. All the precursors share similar overall structures. There is a typical prohormone processing signal (Lys-Arg) located between the acidic propiece and the mature peptide. The antimicrobial peptide family of esculentin-2 is firstly reported in the genus of Amolops. Combined with previous reports, a total of four antimicrobial peptide families have been identified from the genus of Amolops; three of them are also found in the genus of Rana. These results suggest the possible evolutionary connection between the genera Amolops and Rana.  相似文献   

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