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1.
2.
The harpacticoid copepod subfamily Thompsonulinae Lang, 1944, formerly recognized as belonging to the family Tachidiidae (Lang, 1948) is raised to family rank and redefined to include only the genera Thompsonula T. Scott and Caribbula gen. nov. Thompsonula hyaenae (I. C. Thompson) and T. curticauda (Wilson) are redescribed and refigured. Re-examination of the original material showed that Wilson's Rathbunula agilis is synonymous with T. curticauda and not with T. hyaenae , as suggested by Lang (1948). It is now clear that the two species of Thompsonula have distinct distributions, T. curticauda being confined to the North American continent and T. hyaenae to western Europe and the Mediterranean. The genus Caribbula is established to accommodate the type species, T. hyaenae elongata (Gee) and C. fleegeri sp. nov. which are described and figured. The genus Caribbula is distinguished from Thompsonua , primarily by the unique sexual dimorphism on the exopod of P4 and, at present, is known only from the eastern seaboard of the United States and Gulf of Mexico. The genera Danielssenia, Psammis, Paradanielssenia, Micropsammis and Leptotachidia are tentatively assigned to the family Paranannopidae Por.  相似文献   

3.
With the discovery of Alteuthoides kootare gen. et sp. no v. , found living inside an hexactinellid sponge from offshore waters of New Zealand, and the synonymization herein of Paralteutha T. Scott with Eupelte Claus, the number of genera in the harpacticoid copepod family Peltidiidae Sars now stands at eight. In the morphology of the maxillipeds and the armature of the first leg exopods, Alteuthoides is most similar to Alteuthella (A. Scott) and Alteuthellopsis Lang. These shared apomorphies are regarded as convergent ecological specializations to a lifestyle as close associates of other marine invertebrates. Results of a cladistic analysis further assist in the interpretation of relationships within the family. Lang's speculation that Peltidium and Parapeltidium form an independent lineage from the ancestral peltidiid gains further support. Alteutha remains as the basal group to the second lineage in comparison with which all remaining genera are derived in some respect. Alteuthellopsis would appear to be the most advanced genus in the family. Because of recent additions to Neopeltopsis Hicks and Alteuthellopsis , revised diagnoses, together with a revised key to genera, are also presented.  相似文献   

4.
The harpacticoid copepod Danielssenia perezi Monard, 1935 is redescribed on the basis of the only available material from the Scilly Isles off south-west Britain. Sentirenia gen. nov is erected because this species exhibits significant differences from the type species Danielssenia typica Boeck, 1872 in the structure of the antennule; the presence of sensory aesthetascs on, and structure of, the mandible, maxillula and maxilla; the form of the female P5; the setation of the swimming legs and details of the sexual dimorphism on the endopod of the male P2. Further, it is shown that the characters by which D. paraperezi Soyer, 1970 was originally distinguished from D. perezi are no longer valid and D. paraperezi is a junior synonym of S. perezi which now assumes a boreo-mediterranean distribution. A re-examination of the type material of D , eastwardae Coull, 1971 shows that this species is identical to S. perezi in the structure of the mouthparts (including the presence of aesthetascs on the mandible, maxillula and maxilla) and setation of P1–P5. However, within the genus Sentirenia, its specific status is maintained by virtue of a 5-segmented female antennule; a difference in the shape of the endopodal lobe of the female P5; the sexually dimorphic characters of the male P2 endopod; and variation in the ornamentation of some appendages.  相似文献   

5.
Phylogenetic relationships within the brown algal order Sphacelariales and with its sister group were investigated using chloroplast-encoded psbC and rbcL DNA sequences. A pilot study with 21 non-sphacelarialeans, representing nine orders (and some incertae sedis taxa), showed a strongly supported monophyly of the Sphacelariales with its sister taxa Phaeostrophion irregulare, Bodanella lauterborni and Heribaudiella fluviatilis. These three taxa were selected as outgroup for further analyses including DNA sequences of 30 sphacelarialean specimens representing all but two of the recognized genera (Phloiocaulon and Ptilopogon were not sampled). Bayesian Inference and Maximum Likelihood trees showed some incongruence with Maximum Parsimony trees. Trees based on rbcL showed some incongruence with trees based on psbC and combined alignments. Phylogenetic results were used as the basis for a newly proposed classification of the Sphacelariales that reflects evolutionary history. The Sphacelariales is subdivided into four families: Cladostephaceae (monotypic), Sphacelariaceae, Stypocaulaceae, and a newly created monotypic family Sphacelodermaceae to incorporate Sphaceloderma caespitula, comb. nov. (former Sphacelaria caespitula). Sphacelaria radicans is transferred to a newly created genus Protohalopteris and classified in the Stypocaulaceae, which also contains the two unsampled genera Phloiocaulon and Ptilopogon as well as the genus Halopteris. The genera Stypocaulon and monotypic Alethocladus were merged with Halopteris. The Sphacelariaceae were subdivided into six genera including Sphacelaria (consisting only of the former subgenus Propagulifera) and the monotypic Sphacella. Herpodiscus durvillaeae, Sphacelaria pulvinata and the Sphacelaria subgenera Bracteata and Reinkea were merged in an emended Herpodiscus. A new genus Sphacelorbus was created for Sphacelaria nana. Battersia was reinstated for Sphacelaria mirabilis and the subgenus Pseudochaetopteris, except for Sphacelaria plumosa for which Chaetopteris was reinstated.  相似文献   

6.
记述龙蝎蛉新科Drakonochoristidae fam. nov.和1新亚科及其2新属、种和1个老亚科。2新属种的化石标本采自中国陕西铜川中三叠统铜川组下段上部的灰绿色泥岩和页岩。新科性质及其分类位置在文中进行讨论。新科的建立填补这个类群在中国的空白,同时对于小蝎蛉科Nannochoristidae和二叠蝎蛉科Permochoristidae的演化关系的研究有一定的意义。这些新属、种系陕西昆虫群(陕西生物群的一个类别)铜川昆虫组合的新成员。铜川组的时代相当于欧洲拉丁尼期(Ladinian Stage)。  相似文献   

7.
Spongiopsyllus adventicius n. gen., n. sp. is a siphonostomatoid copepod found associated with sponges from Bahia and Pernambuco states, northeast of Brazil. The new genus has three postgenital urosomites in females and four in males, while all the other genera in the family have no more than two and three postgenital urosomites in females and males, respectively.  相似文献   

8.
The Cephalomalthinus semifumatus species group, referred to as the “semifumatus” group henceforth, is interesting because of its heterogeneous morphology resembling either Cephalomalthinus Pic, 1921 or Rhagonycha Eschscholtz, 1830. To elucidate its phylogenetic status, mitochondrial genomes of four species of the “semifumatus” group, 11 Cephalomalthinus species, and 11 Rhagonycha species were sequenced and examined. All analysed mitogenomes were similar with respect to genome size, nucleotide composition, and AT content. Surprisingly, a rearrangement of the trnW-trnC and trnY genes was detected in the “semifumatus” group, presumably caused by tandem duplication and random loss events. Furthermore, genetic distance analyses showed that the proximity of the “semifumatus” group to Cephalomalthinus and to Rhagonycha was comparable to that between the latter two. Moreover, the produced phylogeny strongly supported the monophyly of the “semifumatus” group, and molecular clock analyses dated its divergence from Cephalomalthinus to 32.52 Ma. Thus, the new genus Amphimorphus gen. nov. is suggested to comprise the “semifumatus” group, in which the observed gene rearrangement was a synapomorphy. Moreover, morphological evidence regarding the unique structure of the aedeagus supported this separation. These results indicate that mitochondrial gene rearrangement provide important phylogenetic implications for revising Cephalomalthinus, a speciose genus that is puzzling in the morphology-based taxonomy.  相似文献   

9.
More than ten extinct Lower Brachycera families have been discovered throughout the world. These fossil records are of great significance in piecing together jigsaw puzzles of evolution for the Order Diptera. However, the distinct systematic relationships of the Diptera, one of the four largest orders, remain obscure. Herein, we erect a new family to enhance our systematic understanding of the Diptera. The Uranorhagionidae fam. nov. is a bewildering new extinct family comprising two new genera, Uranorhagio gen. nov. and Strenorhagio gen. nov. , and five new species, Uranorhagio daohugouensis sp. nov. , Strenorhagio deviatus sp. nov. , Strenorhagio grimaldi sp. nov. , Strenorhagio asymmetricus sp. nov. , and Strenorhagio conjugovenius sp. nov. , from the Middle Jurassic of China. Members of the new family are moderate to large in size and robust in shape. This family possesses a peculiar shape of vein R2+3, the basal part of which is strongly fornical and nearly geniculate, and has the crossvein r–m at variable position. Furthermore, the Uranorhagionidae fam. nov. exhibits a mixture of distinct characters of two families in two disparate superfamilies, i.e. Rhagionemestriidae (Nemestrinoidea) and Rhagionidae (Tabanoidea), thus suggesting that this family might be in an inclusive position in dipteran phylogeny. We tentatively place this new family as a member of Tabanoidea, pending the discovery of more fossil specimens and further study. The comparison between the new family and other relative families will be discussed. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 563–572.  相似文献   

10.
Calanoid copepods, belonging to the new genus and species Keraladiaptomus rangareddyi, were collected from temporary ponds in Kerala State, India. The new genus belongs to the family Diaptomidae, subfamily Diaptominae. It is described in detail and its affinity to the related genera, Arctodiaptomus Kiefer, 1932 and Eodiaptomus Kiefer, 1932, discussed.  相似文献   

11.
Rutaraphes shikokuensis gen. et sp. nov. is described from Shikoku, Japan. The new taxon belongs to a group of genera characterized by the lateral sutures demarcating the submentum and is most similar to Neuraphes and Scydmoraphes. Morphological structures of Rutaraphes are illustrated and possible affinities with other genera of Cyrtoscydmini are discussed. Keys to identification of Palearctic and Japanese genera of Cyrtoscydmini are given. Including Rutaraphes, 14 genera of Scydmaeninae are currently known to occur in Japan.  相似文献   

12.
A new species of the basal mosasaurid Halisaurus from the Late Cretaceous (Late Maastrichtian) of the Oulad Abdoun Phosphate Basin of Morocco is described on the basis of both cranial and postcranial remains. H. arambourgi sp. nov. is characterized by unique features of the nares, frontal, parietal, girdle and limb bones. A phylogenetical analysis supports the monophyletic status of Halisaurus ; H. platyspondylus (Maastrichtian, New Jersey), H. ortliebi (Maastrichtian, Belgium) and H. arambourgi form an unresolved polytomy. This study does not support the attribution of ' Halisaurus ' sternbergii (Santonian, Kansas) to Halisaurus nor to any known genus. A new genus, Eonatator , is proposed for the reception of this species, Eonatator sternbergii comb. nov. The new taxon Halisaurinae ( Halisaurus  +  Eonatator ) is the sister-group of more advanced mosasaurids (Natantia). Halisaurines are defined by the shape of the lateral premaxilla–maxilla suture; an oblique contact plane between the parietal and the supratemporal; a preaxial ridge present on the distal two-thirds of the radius length; and tibia and fibula long and slender with slightly expanded extremities.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 447–472.  相似文献   

13.
球革螨科一新属记述(蜱螨亚纲:革螨股)   总被引:3,自引:0,他引:3  
刘井元  马立名 《昆虫学报》2001,44(3):356-359
记述了球革螨科一新属Mirabulbus gen. nov.,包括2种:秦巴异球螨M. qinbaensis sp. nov.和亚东异球螨M.yadongensis (Ma et Wang,1997)。  相似文献   

14.
The marine red algal family Liagoraceae sensu lato is shown to be polyphyletic based on analyses of a combined rbcL and psaA data set and the pattern of carposporophyte development. Fifteen of eighteen genera analyzed formed a monophyletic lineage that included the genus Liagora. Nemalion did not cluster with Liagoraceae sensu stricto, and Nemaliaceae is reinstated, characterized morphologically by the formation of the primary gonimolobes by longitudinal divisions of the gonimoblast initial. Yamadaella and Liagoropsis, previously placed in the Dermonemataceae, are shown to be independent lineages and are recognized as two new families Yamadaellaceae and Liagoropsidaceae. Yamadaellaceae is characterized by two gonimoblast initials cut off bilaterally from the fertilized carpogonium and diffusely spreading gonimoblast filaments. Liagoropsidaceae is characterized by at least three gonimoblast initials cut off by longitudinal septa from the fertilized carpogonium. In contrast, Liagoraceae sensu stricto is characterized by a single gonimoblast initial cut off transversely or diagonally from the fertilized carpogonium. Reproductive features, such as diffuse gonimoblasts and unfused carpogonial branches following postfertilization, appear to have evolved on more than one occasion in the Nemaliales and are therefore not taxonomically diagnostic at the family level, although they may be useful in recognizing genera.  相似文献   

15.
Tomteluva perturbata gen. et sp. nov. and Nasakia thulensis gen. et sp. nov., two new rhynchonelliformean brachiopod taxa, are described from carbonate beds from the lower middle Cambrian (Series 3, Stage 5) basinal Stephen Formation, Canada, and the upper lower Cambrian (Series 2, Stage 4) Henson Gletscher Formation, North Greenland, respectively. The two taxa are characterized by an unusual coral‐like morphology typified by a high conical ventral valve with an anteriorly curved umbo and a tube‐like structure inside the ventral valve, interpreted as pedicle tube. Both resemble the problematic late middle Cambrian (Drumian) species Anomalocalyx cawoodi Brock from Australia, whose systematic affiliation is controversial. Together, the three genera are interpreted as representatives of a new family of rhynchonelliformean brachiopods, the Tomteluvidae fam. nov., which is interpreted as an aberrant or derived taxon within the Order Naukatida. Convergence between the Tomteluvidae and the coralla of small solitary Cambrian coralimorphs, as well as the late Palaeozoic reef‐building richthofenioid brachiopods, might indicate adaptation to a similar life habits and environments. However, their small size (length 4 mm), well‐developed pedicle and perfect morphological symmetry make it more likely that tomteluvids lived attached to frondose algae or sponges, above the seafloor, in a similar fashion to the acrotretoid brachiopods with which they show a high degree of morphological convergence. Morphological features of the pedicle tube of N. thulensis suggest that the tomteluvid pedicle is homologous to that in modern rhynchonelliformean brachiopods. This is the first evidence of the pedicle type within the Naukatida and represents the oldest confirmation of a rhynchonellate pedicle.  相似文献   

16.
17.
The structure of harpacticoid copepod communities of floating detached intertidal algae was studied by surveys and experiments. Seaweed clumps were sampled from Faxaflói, western Iceland, at various distances from the shore (0.2–14 km). Altogether 20 species of harpacticoids were found in these clumps, most of them typical phytal species. Multidimensional scaling ordination (MDS) separated the samples into three distinct clusters in which the communities were significantly different from each other. The distance from shore did not seem to affect the community structure. However, diversity and abundance of harpacticoids increased with size and complexity of the clumps. Experimental Ascophyllum nodosum fronds placed 300–600 m offshore were rapidly colonised by harpacticoids. Density and species diversity were, after 20 days afloat, higher than in the free-floating clumps. Species of the genus Harpacticus were successful colonisers, in particular Harpacticus chelifer and Harpacticus uniremis. In a survey of macrofauna (0.5-mm sieve) on floating algae clumps from various locations around Iceland, H. chelifer was present in all clumps studied, up to 117 km offshore. Its sex ratio was skewed towards females, often with a high ratio of ovigerous females. There was, however, no evidence that this species is using the algal clumps as a platform for reproduction.  相似文献   

18.
SYNOPSIS The following new taxa of septate gregarines are established: METAMERIDAE fam. nov. includes genera Metamera Duke, Deutomera Bhatia & Setna, and Cognettia gen. n., the last with the type and only species C. legeri (Cognetti de Martiis); family GREGARINIDAE Labbé includes Degiustia gen. n. with the type and only species D. hyallela (Batten & DeGiusti); Cirrigregarina gen. n., with the type species C. spissa (Henry) and another species, C. kamenote (Hoshide); and Molluskocystis gen. n., with the type and only species M. pterotracheae (Stuart). Family HIRMOCYSTIDAE (Grassé) includes Arachnocystis gen. n., with the type species A. arachnoidea (Devdhar & Gourishankar) and 3 other species A. nitida (Geus), A. oribatidae (Geus), A. scutovertexi (Erhardová). Family ACTINOCEPHALIDAE (Léger), subfamily Actinocephalinae (Léger), includes Chilogregarina gen. n., with the type species C. striata (Léger & Duboscq) and 3 other species C. brasiliensis (Pinto), C. dujardini (Schneider), and C. stella (Léger).  相似文献   

19.
Shichun  Sun  Jingrang  Lu 《Hydrobiologia》1998,367(1-3):175-187
A new genus and species of heteronemertean, Yinia pratensis gen. nov. and sp. nov., collected from low salinity waters (salinity 0.2–0.4 ‰) at Changjiang River Estuary, is described and illustrated. The species possesses a proboscis with an outer circular and an inner longitudinal muscle layer, and is placed in family Lineidae sensu Gibson. The following combination of morphological features distinguishes the new species from any other genera in this family: proboscis with two muscle crosses; dermis without connective tissue layer between gland cells and body wall outer longitudinal muscle layer; rhynchocoel wall circular muscles not interweaving with adjacent body wall longitudinal muscles; foregut with circular somatic muscles and subepithelial gland cell layer; neurochord cells present in central nervous system; caudal cirrus missing; blood system developed into alimentary plexus extending almost the full length of the body. Another significant character is that the lobular excretory cells are extremely well developed which may represent adaptation to water of low salinity. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

20.
The new oedischiine Palatinoedischia elongata nov. gen., nov. sp., is described from the Early Permian of Germany. It is characterized by a very particular broad area between R+M+CuA and CuP of the tegmen. The possible closest relative of this new taxon is the genus Plesioidischia, also from the Early Permian of Germany. They possibly constitute their own clade, but a comprehensive phylogenetic analysis is needed to clarify the whole superfamily Oedischioidea.  相似文献   

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