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1.
Sphaeralcyon weddellensis gen. nov. et sp. nov. is described and illustrated from three colonies collected in the eastern Weddell Sea on the Polarstern cruises ANT V/3 and ANT VI/3. The new genus is compared with three closely related alcyoniid genera, all having capitate or mushroom-shaped colonies and dimorphic polyps. Sphaeralcyon is readily distinguishable from Malacacanthus by the presence of sclerites (absent in the latter genus), and from Anthomastus by sclerite shape, mainly in the form of tuberculate spheroids, and by the horny periderm on the stalk (absent in Anthomastus). Sphaeralcyon also differs from Verseveldtia in the set of sclerites, which are elongate spiny rods and a different type of tuberculate spheroid, and in the presence of eight-points as anthocodial armature (absent in Verseveldtia). The discovery of this new genus lends further support to the notion that diversity in benthic communities in Antarctica is higher than suggested by previous studies. Accepted: 6 December 1999  相似文献   

2.
Abstract: Large collections of Eccentrotheca helenia sp. nov. from the lower Cambrian Wilkawillina and Ajax limestones in the Arrowie Basin, South Australia, contain abundant low, cap‐shaped and high, laterally compressed isolated sclerites in addition to partially articulated tubular specimens. The scleritome of Eccentrotheca helenia sp. nov. is fully described for the first time and shown to be formed by ontogenetic fusion of sclerites into successively stacked sclerite rings, forming a larger, tubular structure. The apical termination of the tube is highly variable, but is primarily constructed by low, cap‐shaped sclerites and characterised by a central aperture of variable inclination. The adapical portion of the tube is predominantly constructed by high, laterally compressed sclerites, but individual sclerite rings can contain both cap‐shaped and laterally compressed sclerites along with sclerites of intermediate morphology. The apical aperture presumably housed organic structures for attachment to a hard substrate, but the scleritome also occasionally preserves small lateral perforations between fused sclerites, which may have served to stabilise the scleritome by providing additional points of anchorage. In the Arrowie Basin, E. helenia is found in association with archaeocyath‐microbial‐spongiomorph‐dominated bioherms and most likely inhabited pendant or cryptic habitats within these bioherms. Eccentrotheca‐like sclerites form an integral part of the scleritomes of many tommotiids which may confuse taxonomic analysis. Sclerites previously assigned to ‘E.guano, consistently occur together with sclerites of Kulparina rostrata in stratigraphic intervals consistently older than strata hosting E. helenia. Rare fused specimens indicate that the sclerites of K. rostrata and ‘E.guano belong to the same scleritome.  相似文献   

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5.
The family Subergorgiidae comprises two genera, Subergorgia with three species and Annella with two species. All the previously known species are distributed in tropical and subtropical waters from the northern Red Sea to the central Pacific. The presence of a subergorgiid in Antarctic waters could support the hypothesis that at least part of the Antarctic fauna has its origin in the Cretaceous period, when Antarctica was part of the Gondwana continent. The new genus Rosgorgia with the new species inexspectata is placed in the family Subergorgiidae by the presence of smooth, fusiform and often anastomosing needles in the axis, wart spindles in the coenenchyme, and coelenteric cavities of polyps only present in the coenenchyme. The genus Rosgorgia differs from Subergorgia and Annella by the presence of tuberculate rods in the axis. It is further distinguished from Annella by the absence of double-disk sclerites in the coenenchyme, and not anastomosing branches. Accepted: 25 June 2000  相似文献   

6.
Chancelloriids are a group of enigmatic sessile animals that are covered with sclerites shaped as rosettes of spines, producing an appearance like that of a barrel cactus. They are known only from Cambrian rocks. Isolated sclerites of chancelloriids are widespread in small shelly faunas, but they have proven difficult to treat taxonomically due to the variation within and between individual animals. We report on large samples of chancelloriid sclerites from the Meishucunian (pre‐trilobitic Lower Cambrian) of eastern Yunnan Province, China, including material from the Dahai Member of the Zhujiaqing Formation (the Zhujiaqing section, Dahai, Huize County) and the Shiyantou Formation (the Xiaotan section, Yongshan County). The material from the Dahai Member appears to come from a single species, Chancelloriella irregularis. Statistical analysis of morphotype co‐occurrences in different samples suggests that several species are represented in the material from the Shiyantou Formation, which we herein tentatively place in four species, Allonnia erromenosa, Allonnia tetrathallis, Archiasterella charma sp. nov. and Archiasterella cf. pentactina. We suggest therefore that careful study of large collections of isolated chancelloriid sclerites permits the identification of different species, opening the possibility of their use in evolutionary or stratigraphical studies. In particular, in South China, it seems that Chancelloriella irregularis is characteristic of rocks of the Paragloborilus subglobosusPurella squamulosa Assemblage Zone and the Watsonella crosbyi Assemblage Zone, whilst Archiasterella and Allonnia first appear in the overlying Sinosachites flabelliformisTannuolina zhangwentangi Assemblage Zone. C. irregularis is thus amongst the oldest well‐characterized chancelloriids, and the irregularity and poor organization of its sclerites relative to those of younger forms support the hypothesis that chancelloriid sclerites are compound structures arising from the fusion of originally separate elements, perhaps homologous with sclerites of halkieriids and other coeloscleritophorans. The similarity between the arrangement of rays in a chancelloriid sclerite and the arrangement of bubbles in small bubble clusters suggests that in many cases, aspects of the form of chancelloriid sclerites are the result of simple physical processes.  相似文献   

7.
Information on the embryonic development of the malleate trophi in Epiphanidae (Rotifera, Monogononta, Ploima) is presented, based on scanning electron microscopy observations in Rhinoglena fertoeensis, R. frontalis, R. kutikovae, R. tokioensis, and Proalides tentaculatus, to contribute to the understanding of this structure of high evolutionary and functional relevance in Rotifera. The first observable and distinctly sclerotized structures were a double row of median transversal sclerites along the longitudinal axis, wherein the future unci, rostellar scleropili, cristae rami, and basal apophyses became recognizable. Fulcrum and manubria arose subsequently; the fulcrum sclerites were longitudinally ordered in a double layer. The rami chambers developed last as lamellar structures. Unci appeared as separate thin, elongate elements, the primary uncini, developing to uncus plates by transversal growth and apposition of sclerite material on the shafts of the uncini. The heads of the uncini showed their greatest development after fusion of their shafts into uncus plates. The interjacent spaces between the heads functioned as a mold, organizing bundles of sclerites which developed into the uniseriate, zigzag‐shaped cristae rami. The fulcrum attained its definite shape by elongation of the double layer of rod‐shaped sclerites into appressed sclerofibrillae. Manubria became visible as a proximal ridge of sclerites, whereupon a triangular lamella composed of crisscross‐oriented sclerites developed distally, growing out to the manubrial chambers. Ramus chambers originated from two longitudinal amorphous lamellae incorporating the median rami sclerites and closing from distal to proximal; subbasal chambers were formed before the basal chambers.  相似文献   

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Jarms  Gerhard 《Hydrobiologia》1991,216(1):463-470
The tubes of the polyp stages of all known species of the family Nausithoidae have been examined to find characters useful for specific identification. Such characters comprise both internal and external structures of the chitinous exoskeleton, measurements of the periderm, and the shape of the tubes defined by the Formquotient. A key for the polyp generation is given based on these characters. The long-term rearing of several species and elucidation of their life cycles has also enabled a key to the medusa generation of the Nausithoidae to be constructed. Stephanoscyphistoma gen. nov. is proposed for the polyps of all species of coronates of uncertain medusa genus.  相似文献   

10.
The association of isolated remains of lobopods with a netlike structure, including plates of Microdictyon rozanovi sp. nov. and sclerites with spinelike process of Onychomicrodictyon spiniferum gen. et sp. nov., as well as saberlike sclerites of Protohertzina yudomica sp. nov. interpreted as grasping spines of chaetognaths, is described from the middle part of the Inikan Formation of the Toyonian Stage of the Lower Cambrian (Lermontovia dzevanovskii Zone). The diagnoses and species composition of the genera Microdictyon and Protohertzina are refined.  相似文献   

11.
Sasakawa K 《Zoological science》2005,22(11):1205-1216
A phylogenetic hypothesis of the subgenus Nialoe (s. lat.) of genus Pterostichus is proposed based on a cladistic analysis of seventeen morphological characters. Through comparative studies of the sclerites on the endophallus of male genitalia, it became apparent that the arrangement of these sclerites reflects seven different origins. The results show that Nialoe (s. lat.) is monophyletic and composed of four clades, while some traditional taxa are para- or polyphyletic, and are defined only by symplesiomorphies. Pterostichus (Nialoe) mosaicus sp. nov., which is indispensable for tracing the homology of sclerites in this subgenus, is described.  相似文献   

12.
Three new species ofCrinipellis (Agaricales, Basidiomycetes) in Japan are described and illustrated:Crinipellis canescens sp. nov., forming small, canescent basidiomata, was found on a dead fallen twig in the subtropical laurelleaved forest of Iriomote Island (southwestern Japan);Crinipellis corvina sp. nov., forming fibrillose-strigose, puriplish black hairs enveloping the whole basidioma, was found on bark ofTorreya nucifera in Mt. Takao, Tokyo;Crinipellis nigricaulis sp. nov., having a reddish brown pileus with a minute, black papilla and a blackish stipe accompanied by blackish, branched rhizomorphs, was found on leaf litter in the lowland forest of Kanagawa.  相似文献   

13.
Three marine scuticociliates, Falcicyclidium fangi nov. gen., nov. spec., Falcicyclidium atractodes nov. spec., and Cristigera media Kahl, 1928 were investigated using live observation and silver impregnation methods. The genus Falcicyclidium is distinguished by the combination of: (i) dorsoventrally flattened body, (ii) hook-like (falciform) paroral membrane, (iii) anterior end of paroral membrane posterior to anterior end of membranelle 1, and (iv) multiple caudal cilia. Falcicyclidium fangi nov. spec., the type of the new genus, can be recognized by the combination of its large size, extremely dorsoventrally flattened (3:1) body, consistently 10 somatic kineties, and the broad, elongate buccal area occupying 60% of the body length. Falcicyclidium atractodes nov. spec. is mainly characterized by a unique spine projecting from both the anterior and posterior end. The uncommon form, Cristigera media is redescribed based on the population from Qingdao, the statistic data and additional features, especially the morphology of the living cells, are documented.  相似文献   

14.
A new soft coral species of the genus Nidalia, from seamounts to the south of the Azores Archipelago is described. The main features of Nidalia aurantia n. sp. are as following: colony torch-like, a capitulum light orange in colour, not laterally flattened, dome-shaped and not distinctly projecting beyond the stalk, an introvert with sparse sclerites transversally placed, and an anthocodial crown with 13–17 sclerite rows. The new species is compared with its closest congeners. This is the first time that a species of Nidalia has been located in the Mid-Atlantic Ocean.  相似文献   

15.
Silicified wood collected from the Lower Miocene Nawamata Formation at two localities, Nakaya and Nigoriike, Monzen-machi, Noto Peninsula, central Japan, were identified. Among the 58 specimens there are two species of conifers and eleven species of dicotyledons:Taxodioxylon cunninghamioides (Watari) Watari andT. sequoianum (Merckl.) Gothan (both Taxodiaceae),Carya protojaponica Watari (Juglandaceae),Pterocarya rhoifolia Siebold et Zucc. (Juglandaceae),Ostrya monzenensis sp. nov. (Betulaceae),Quercus anataiensis (Watari) Watari (Fagaceae),Liquidambar hisauchii comb. nov. (Hamamelidaceae),Prunus iwatense (Watari) Takahashi et Suzuki (Rosaceae),Gleditsia paleojaponica comb. nov. (Leguminosae),Acer watarianum Takahashi et Suzuki (Aceraceae),Meliosma mio-oldhami sp. nov. (Sabiaceae),Reevesia miocenica Watari (Sterculiaceae), andFraxinus notoensis sp. nov. (Oleaceae). The fossil wood floras at the two localities are compared to the Daijima Flora, and warm-and/or cool-temperate mesic forests are suggested to occur in the Early Miocene of Monzen.  相似文献   

16.
Prompted by field observations in 2001 in the Utcubamba Valley, Peru, a study was undertaken of 130 specimens in the Aratinga mitrata complex. As a result, the traditional arrangement of Aratinga mitrata (A. m. mitrata Tschudi 1844 and A. m. alticola Chapman 1921) as one species, is replaced with a new classification where Aratinga mitrata is divided into five taxa, A. m. mitrata Tschudi 1844, Aratinga mitrata chlorogenys ssp. nov and Aratinga mitrata tucumana ssp. nov, Aratinga hockingi sp. nov, and A. alticola Chapman 1921.  相似文献   

17.
The phylogeny ofFumariaceae, as inferred fromrps16 intron sequences, is compared with morphological data, and nrDNA-ITS. The different data sets are largely congruent and indicate that (1)Dicentra and the tribeCorydaleae as hitherto circumscribed are polyphyletic, (2)Lamprocapnos (=Dicentra spectabilis) is sister group to the rest of subfam.Fumarioideae, (3)Ehrendorferia, gen. nov. (=Dicentra chrysantha andD. ochroleuca) is basal in the latter group, (4) the morphologically aberrantIchtyoselmis, gen. nov. (=Dicentra macrantha) groups withDicentra s. str., (5) the genusCysticapnos should be included in the tribeFumarieae, (6)Dactylicapnos (=Dicentra subg.Dactylicapnos) is sister group toCorydalis, (7) the genusCorydalis is monophyletic, and consists of three subgenera:Chremnocapnos, stat. nov.,Sophorocapnos, stat. nov., andCorydalis. The following new combinations are validated:Ehrendorferia chrysantha, E. ochroleuca, Ichtyoselmis macrantha, andLamprocapnos spectabilis. Dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer on the occasion of his 70th birthday  相似文献   

18.
Fain  A. 《Systematic parasitology》1981,2(3):181-205
Summary The genus Ornithocheyletia Volgin, 1964 is revised. If the three species described below are included the number of known species in this genus is now 22. These species live on or in the skin of birds and produce mange. The holotypes of all these species have been examined except those of O. pinguis (Berlese) and of O. dubinini Volgin which were not available. Three new species and one new subspecies are described: O. geopeliae sp. nov. from Geopelia striata, O. lepidus sp. nov. from Garrulax leucolophus bicolor, O. eulabes from Eulabes javana and O. psittaci poicephali ssp. nov. from Poicephalus senegalus. O. similis Fain, 1972 is placed as a subspecies of O. hallae Smiley, 1970. The genus Ornithocheyletia is redefined and a key to the species is provided. The following stages have been observed in the life cycle: egg—prelarva—larva— protonymph—tritonymph—adults. A prelarva is observed for the first time: it is represented by a small ecdysis organ consisting of two small bifid sclerites serving for the rupture of the eggshell. The adult female develops into a tritonymph, the adult male into a protonymph. The males are either homeomorphic or heteromorphic; the latter are characterized by the hypertrophy and modification of the gnathosoma, especially the palps. ac]19800531  相似文献   

19.
Three new species belonging toMarasmius sectionSicci (Agaricales) are described and illustrated from eastern Honshu, Japan:Marasmius nocturnus sp. nov., forming a dark brown pileus and marginate lamellae, was found on leaf litter inPasania—Quercus forests;Marasmius occultatus sp. nov., producing brownish orange or light brown basidiomata and long, cylindrical-fusoid basidiospores, was found on dead fallen twigs ofAphananthe aspera andQuercus myrsinaefolia;Marasmius opulentus sp. nov., having a reddish orange pileus and a pubescent stipe, was found on leaf litter in laurel-leaved forest.  相似文献   

20.
Two new species of the sectionMarginatae are described, namely,Inocybe populea sp. nov. andI. leptoclada sp. nov., from western Japan and eastern Japan, respectively.Inocybe leptoclada is assigned to sectionMarginatae, even though it lacks a marginate bulb.Inocybe populea is placed in the sectionMarginatae because of the presence of a marginate (often indistinct) bulbous base of stipe and the caulocystidia throughout. The discoveries ofI. leptoclada andI. populea provide further evidence that sectionMarginatae and sectionInocybe [=Cortinatae] are poorly defined.  相似文献   

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