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1.
The cyclostome bryozoans constitute an old and divergent group of bryozoans, whose muscle and nervous systems are poorly known. The entire neuromuscular system of the cyclostome Crisia eburnea is here mapped with phalloidin, DAPI and antibodies directed against acetylated α-tubulin and serotonin. Innervation of most muscles as well as the ganglion of C. eburnea is described, and several new details are reported, for example, on the additional and branched ectodermal muscles of the cystid, the presence of subtentacular muscles, the retractor muscles being distinctly striated and the presence of an additional pair of lateroabfrontal nerves in the proximal part of the tentacles. The serotonin-like immunoreactivity in the nervous system of C. eburnea shares many features with those of the other bryozoans studied so far, which probably reflects a common ancestry of the neural architecture. However, the nervous system shows somewhat less complexity compared to that of the sister clade, Eurystomata, and contains fewer cells and nerves compared to the cyclostome Cinctipora which has much larger zooids and more than eight tentacles. No interzooidal neural connections were found in C. eburnea, which is in agreement with the individual response of the zooids.  相似文献   

2.
Five new bryozoan species (Buffonellaria cornuta, Lagenipora chedopadiensis, Turbicellepora canui, T. naniberensis andT. rostrata) belonging to the family CelleporidaeHINCKS, 1884 are described and illustrated from the Tertiary sequences of western Kachchh, Gujarat, India. The zoaria of these species comprise about 17 percent of total cheilostome bryozoan colonies from Kachchh in the present collection, and those ofTurbicellepora rostrata n. sp. account for over 64 percent of the celleporid specimens. These records of celleporids enrich our knowledge of the fossil occurrence of this group during the Early Miocene in the Indo-Pacific province.  相似文献   

3.

Introduction

Among bryozoans, cyclostome anatomy is the least studied by modern methods. New data on the nervous system fill the gap in our knowledge and make morphological analysis much more fruitful to resolve some questions of bryozoan evolution and phylogeny.

Results

The nervous system of cyclostome Crisia eburnea was studied by transmission electron microscopy and confocal laser scanning microscopy. The cerebral ganglion has an upper concavity and a small inner cavity filled with cilia and microvilli, thus exhibiting features of neuroepithelium. The cerebral ganglion is associated with the circumoral nerve ring, the circumpharyngeal nerve ring, and the outer nerve ring. Each tentacle has six longitudinal neurite bundles. The body wall is innervated by thick paired longitudinal nerves. Circular nerves are associated with atrial sphincter. A membranous sac, cardia, and caecum all have nervous plexus.

Conclusion

The nervous system of the cyclostome C. eburnea combines phylactolaemate and gymnolaemate features. Innervation of tentacles by six neurite bundles is similar of that in Phylactolaemata. The presence of circumpharyngeal nerve ring and outer nerve ring is characteristic of both, Cyclostomata and Gymnolaemata. The structure of the cerebral ganglion may be regarded as a result of transformation of hypothetical ancestral neuroepithelium. Primitive cerebral ganglion and combination of nerve plexus and cords in the nervous system of C. eburnea allows to suggest that the nerve system topography of C. eburnea may represent an ancestral state of nervous system organization in Bryozoa. Several scenarios describing evolution of the cerebral ganglion in different bryozoan groups are proposed.
  相似文献   

4.
Two new bryozoan species of the trepostome family Dyscritellidae,Dyscritellopsis thaynesianus n. sp. andDyscritellopsis montelloensis n. sp., are described from the Early Triassic (Smithian/Spathian) Thaynes Limestone, Nevada (USA). The bryozoan fauna documents the survival of Paleozoic lineages into the earliest Triassic on northern open shelves outside the tropics. The fauna holds paleobiogeo-graphic connections to the Early Triassic bryozoan faunas of Spitsbergen.   相似文献   

5.
Cyclostomata bryozoa are thought to reproduce via polyembryony, a clonal replication of a fertilized egg. To test this hypothesis and to assess the impact of their reproductive strategy on the structure of populations, we isolated microsatellite markers in Crisia denticulata (Cyclostomata, Stenolemata), using an initial enrichment step with random amplified polymorphic DNA (RAPD) primers. A total of nine microsatellites, one tetra‐ and eight dinucleotides repeats were isolated; seven were found to be polymorphic in a test sample of 30 individuals, with allele numbers/locus varying from 2 to 6. The tetranucleotide locus showed heterozygote deficiency. These primers did not amplify the DNA of Crisia eburnea.  相似文献   

6.
The genus Cales (Hymenoptera: Aphelinidae) includes 13 species worldwide, of which 10 form a highly morphologically uniform species complex with a native range in the Neotropical region. We recognize ten species previously attributed to a single Neotropical species, Cales noacki Howard, which in the strict sense is a species broadly disseminated to control woolly whitefly. A neotype is designated for C. noacki, and it is redescribed based on specimens molecularly determined to be conspecific with the neotype. Newly described species include: C. bicolor Mottern, n.sp ., C. breviclava Mottern, n.sp ., C. brevisensillum Mottern n.sp ., C. curvigladius Mottern, n.sp ., C. longiseta Mottern, n.sp ., C. multisensillum Mottern n.sp ., C. noyesi Mottern, n.sp ., C. parvigladius Mottern, n.sp . and C. rosei Mottern, n.sp . Species are delimited based on a combination of morphological and molecular data (28S‐D2 rDNA and COI). Additional specimens are included in the phylogenetic analyses and although these likely represent several new species, we lack sufficient specimen sampling to describe them at this time. Cales are highly morphologically conserved and character‐poor, resulting in several cryptic species. A molecular phylogeny of the known Neotropical species based on 28S‐D25 rDNA and a 390‐bp segment of COI is included, and identification keys to males and females are provided. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:7FEB0479‐9B2E‐48E8‐8603‐4B7C2759D4EC .  相似文献   

7.
Independent sucking/swallowing pharynges, as found in members of at least ten animal phyla, are pharynges that are opened by muscles that are not attached to the outer body wall. Their musculature is derived from either mesoderm or ectoderm, the latter taking the form of a myoepithelium. I review results of previous work on the morphology of independent sucking/swallowing pharynges among invertebrates and provide new information on the ultrastructure of the pharynx of the cyclostome bryozoan Crisia eburnea. The various morphologies of this type of pharynx have been used in some phylogenetic considerations, but only the myoepithelial sucking pharynx with a triradiate lumen was considered significant in analyses of relationships between phyla. However, I argue that this shape is the only one that makes an efficient suction pump, and this, together with different orientations of the myoepithelial pharyngeal pump and its phylogenetic distribution, indicates that the triradiate myoepithelial pharynx has evolved convergently in a number of lineages.  相似文献   

8.
A bryozoan fauna containing seven species is described from the Upper Frasnian (Upper Devonian) rocks in the Khoshyeilagh Section, Alborz Mountains (northern Iran). The studied bryozoan assemblage includes one new trepostome species, Eridotrypella alborzensis sp. nov., an additional four species identified at species level: two trepostomes, Minussina akkayaensis Volkova, 1974 and Leptotrypella inaudita Morozova, 1961, and two rhabdomesine cryptostomes, Bigeyella mariae (Morozova, 1961) and Saffordotaxis multispinata (Morozova, 1955). Furthermore, two species are described in open nomenclature: the trepostome Schulgina sp. and the rhabdomesine cryptostome Nicklesopora sp. The studied fauna shows a close similarity at the species level between northern Iran and the Altai-Sayan Folded Belt (Russia), south China, and Transcaucasia.  相似文献   

9.
10.
The Lower to Middle Devonian Santa Lucia Formation of NW Spain contains a rich and well-preserved bryozoan fauna. An assemblage containing 14 species is described from two localities in Cantabrian Mountains, Abelgas, and Paradilla. One new genus with one new species is described: Isostylus abelgasensis n. sp. n. gen. Another two new species have been found: Microcampylus minor n. sp. and Acanthoclema parvula n. sp. Additionally, the following species were identified: Cyclotrypa communis (Ulrich 1890), Fistuliphragma gracilis Ernst 2008a, Leioclema attenuatum Duncan 1939, Hemitrypa cf. tenella Barrande in Počta 1894, Fenestella aff. parallela Hall 1881, Anastomopora adnata (Hall 1883), Semicoscinium rhombicum Ulrich 1890, Quadrisemicoscinium discretum (Prantl 1932). Three species are described in open nomenclature: Trepostomata sp. indet.1 and 2, and Semicoscinium sp. The described bryozoan fauna shows connections to the Lower Devonian of Bohemia, and to the Middle Devonian of Rhenish Massif and North America.  相似文献   

11.
The larval stages ofAblattaria arenaria were provided with 4 different snail species:Monacha syriaca (Ehrenberg),Xeropicta derbentina (Krynicki),Candidula sp., andZebrina eburnea (Pfeiffer) to determine if the prey species affected developmental time and food preference of larvae. Functional response of each larval stage ofA. arenaria was also tested for increasing density ofX. derbentina, the most common prey species found in association withA. arenaria locally. The developmental time of each larval stage did not show any statistical difference when fed with different snail species. The total developmental time from egg hatch to adult emergence was 19.0, 19.1, 18.0 and 21.4 days for prey speciesM. syriaca, X. derbentina, Candidula sp., andZ. eburnea, respectively. When prey was offered to larvae either as a single species or as combination of several species,M. syriaca was the most preferred. The prey least consumed wasCandula sp. when prey was given separately, andZ. eburnea was least preferred when other prey species were present in the arena. The 3rd larval stage did not eat anyZ. eburnea if other prey species were present. The amount of prey consumed by the 1st larval stage did not show any statistical differences with increasing density ofX. derbentina. But the response of 2nd and 3rd larval stages was very similar to each other although the amount of prey they consumed was very different. They both showed a rapid increase in consumption rate at early densities, then a negatively but slowly accelerated rise to plateaus at higher densities, a type-2 functional response curve. All larval stages were very sensitive to starvation. Mortality started after the 2nd day, and all individuals of all larval stages were dead by the 5th day.   相似文献   

12.
Bryozoans from the Mitikha Formation (Lower Famennian, Upper Devonian) in the Kuznetsk depression are described for the first time. This bryozoan assemblage comprises both the well-known species Leioclema numerosum Moroz., L. ramosum Nekh., and Nicklesopora graciosa Troiz. and new taxa: L. kusmense sp. nov. and Megacanthopora glubokaensis sp. nov. The bryozoan assemblage contains some species common with the Famennian bryozoan assemblage of Kazakhstan.  相似文献   

13.
Five new nematode species are described from a mangancsc nodule area of the abyssal eastern South Pacific: Enoploides tyrannis sp. n., Paramesacanthion abyssorum sp. n., P. forcepssp. n. (all three Thoracostomopsidae), Phylloncholaimus immanis gen. et sp. n. (Oncholaimidac), and Eurystomina absoluta sp. n. (Enchelidiidae). They are characterized by large size (body length 5000–23000 μm), short tails (c = 17–33), and strongly cuticularizcd, barrel-shaped buccal cavities with large teeth. With the exception of one male of E. tyrannis from the surface of a manganese nodule, all other specimens were found in the sediment. The new species are sporadic in distribution and represented by few individuals.  相似文献   

14.

Two tribes of the subfamily Typhlocybinae are represented in New Zealand, as follows. Erythroneurini: the cosmopolitan genus Zygina is represented by 4 endemic species—toetoe, ramsayi n.sp., dumbletoni, and agni n.sp.—plus zealandica, which occurs in Australia also. Typhlocybini: Typhlocyba froggatti, T. lethierryi, Ribautiana tenerrima, Eupteryx melissae, Kybos smaragdula, and K. betulicola are introduced Northern Hemisphere elements; Matatua montivaga n.gen.&sp. is endemic; M. maorica (formerly Dikraneura maorica), also endemic, is of uncertain identity in the absence of male specimens. Keys are given for the separation of all taxa, the genera and species are described, and all species except Matatua maorica are figured.  相似文献   

15.
The cribrimorph bryozoan Puellina setosa (Waters) is reviewed, together with a closely related species, Puellina gattyae (Busk), and two new Cribrilaria species from the Mediterranean, C. cassidainsis sp. n. and C. minima sp. n., which present some characters in common with P. setosa and were previously confused with it.  相似文献   

16.
New data and records of the genus Chrysotoxum Meigen, 1803 are reported, arising from taxonomic and faunistic examination of adult specimens collected from 1920 to 2011 from four northeastern provinces of Turkey (Erzurum, Bayburt, Kars, and Artvin), and from the neighboring countries of Armenia, Azerbaijan and Iran. Three new species are described: Chrysotoxum antennalis Vuji?, Nedeljkovi? &; Hayat sp. n., C. clausseni Vuji?, Nedeljkovi? &; Hayat sp. n. and C. persicum Vuji?, Nedeljkovi? &; Hayat sp. n. The first two are known only from northeastern Turkey, and the third also occurs in Armenia, Azerbaijan and Iran. These new species have in common an antenna with the basoflagellomere being shorter than the scape and pedicel together.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:4C264678-8E47-4DE0-AC7D-91DABC597BCD  相似文献   

17.
TheBeothuka terranova radiolarian assemblage from theIsograptus victoriae lunatus Biozone of western Newfoundland is described and compared with the slightly older assemblage from theDidymograptellus bifidus Biozone of Spitsbergen. Specimens ofBeothuka terranova are described for the first time from material preserved in silica with little diagenetic changes. In the Spitsbergen specimens the skeleton is replaced by pyrite, destroying most of the original details and thickening distinctly fine bars and spines. The Newfoundland assemblage lacks specimens ofSphaeroentactinia, while possible specimens ofSvalbardospiculum andProtoentactinia sp. are represented by juveniles.Nyfrieslandia specimens are common in the sample. Faunal differences may relate to preservational factors and, in part indicate biostratigraphic differences. Several new species are described, some in open nomenclature:Antygopora irregularia n. sp.,Labyrinthia robusta n. sp.  相似文献   

18.
Two bryozoan species are described from the Geirud Formation (Upper Devonian/Lower Carboniferous) of Central Alborz (Iran). Trepostome Schulgina mutabilis Troizkaya, 1975 is known from the Upper Devonian (Famennian) of Central Kazakhstan. The new species Ascopora geirudensis n. sp. is the earliest known representative of the rhabdomesine genus Ascopora Trautschold, 1876.  相似文献   

19.
Abstract. This paper revises the bees currently considered to belong to the genus Rhectomia s.l. and proposes a species phylogeny based on morphological characters, using other Corynurina as outgroups. The results indicate that Rhinocorynura Schrottky renders Rhectomia s.l. paraphyletic. Consequently, Corynurella is removed from synonymy with Rhectomia s.s., and Paracorynurella gen.n. is proposed. The topology among these genera is: outgroup [(Rhectomia s.s. + Rhinocorynura) (Paracorynurella gen.n. + Corynurella)]. Nine species are assigned to Corynurella: C. brokopondoi sp.n. , C. caerulea sp.n. , C. cognata sp.n. , C. decora sp.n. , C. harrisoni (Engel), C. mourei Eickwort, C. nigra sp.n. , C. singularis sp.n. and C. triangulata sp.n. Three new species are described in Paracorynurella gen.n. : type species P. betoi sp.n. , P. excavata sp.n ., P. reticulata sp.n. ; P. difficillima (Ducke) comb.n. is transferred from Rhinocorynura. Three species are recognized in Rhectomia s.s.: R. catarina sp.n. , R. liebherri Engel and R. pumilla Moure. The male of R. liebherri is described for the first time. Keys for the identification of the genera and species are provided.  相似文献   

20.
Four new micropterous species of the genus Sunius Curtis, 1829 are described and illustrated from western Anatolia: Sunius akdaghensis sp. n. from Kütahya province, Sunius ciceki sp. n. from Bal?kesir province, Sunius ozgeni sp. n. and Sunius cagatayi sp. n. from Denizli province. Additional records are presented for three species. The genus Sunius is now represented in Turkey by 36 species.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:F3808D28-65E9-4619-A350-781C971701EC  相似文献   

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