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Journal articles on the topic 'Umbilicity'

Author: Grafiati

Published: 4 June 2021

Last updated: 25 July 2025

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1

Antić, Miroslava, Marilena Moruz, and Joeri Van der Veken. "H-Umbilical Lagrangian Submanifolds of the Nearly Kähler \( {\mathbb{S}^3\times\mathbb{S}^3} \)." Mathematics 8, no. 9 (2020): 1427. http://dx.doi.org/10.3390/math8091427.

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H-umbilicity was introduced as an analogue of total umbilicity for Lagrangian submanifolds since, in some relevant cases, totally umbilical Lagrangian submanifolds are automatically totally geodesic. In this paper, we show that, in the homogeneous nearly Kähler S3×S3, also H-umbilical Lagrangian submanifolds are automatically totally geodesic.

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2

Izumiya, Shyuichi, Donghe Pei, and María del Carmen Romero Fuster. "Umbilicity of space-like submanifolds of Minkowski space." Proceedings of the Royal Society of Edinburgh: Section A Mathematics 134, no. 2 (2004): 375–87. http://dx.doi.org/10.1017/s0308210500003267.

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We study some properties of space-like submanifolds in Minkowski n-space, whose points are all umbilic with respect to some normal field. As a consequence of these and some results contained in a paper by Asperti and Dajczer, we obtain that being ν-umbilic with respect to a parallel light-like normal field implies conformal flatness for submanifolds of dimension n − 2 ≥ 3. In the case of surfaces, we relate the umbilicity condition to that of total semi-umbilicity (degeneracy of the curvature ellipse at every point). Moreover, if the considered normal field is parallel, we show that it is ever

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3

DE LIMA, EUDES L., and HENRIQUE F. DE LIMA. "COMPLETE WEINGARTEN HYPERSURFACES SATISFYING AN OKUMURA TYPE INEQUALITY." Journal of the Australian Mathematical Society 109, no. 1 (2019): 81–92. http://dx.doi.org/10.1017/s1446788719000028.

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In this paper we deal with complete linear Weingarten hypersurfaces immersed into Riemannian space forms. Assuming an Okumura type inequality on the total umbilicity tensor of such hypersurfaces, we prove that either the hypersurface is totally umbilical or it holds an estimate for the norm of the total umbilicity tensor, which is also shown be sharp in the sense that the product of space forms realize them. Our approach is based on a version of the Omori–Yau maximum principle for a suitable Cheng–Yau type operator.

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4

Aquino, Cícero P., Márcio Batista, and Henrique F. de Lima. "On the umbilicity of generalized linear Weingarten hypersurfaces in hyperbolic spaces." Advances in Geometry 18, no. 4 (2018): 425–30. http://dx.doi.org/10.1515/advgeom-2018-0005.

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Abstract We deal with complete generalized linear Weingarten hypersurfaces immersed in hyperbolic spaces. Under appropriate constraints on the image of the Gauss map, we present suitable conditions which guarantee the umbilicity of these hypersurfaces.

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5

COLARES, ANTONIO GERVASIO, and FERNANDO ENRIQUE ECHAIZ-ESPINOZA. "CONSTANT SCALAR CURVATURE HYPERSURFACES WITH SECOND-ORDER UMBILICITY." Glasgow Mathematical Journal 51, no. 2 (2009): 219–41. http://dx.doi.org/10.1017/s0017089508004643.

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AbstractWe extend the concept of umbilicity to higher order umbilicity in Riemannian manifolds saying that an isometric immersion is k-umbilical when APk−1(A) is a multiple of the identity, where Pk(A) is the kth Newton polynomial in the second fundamental form A with P0(A) being the identity. Thus, for k=1, one-umbilical coincides with umbilical. We determine the principal curvatures of the two-umbilical isometric immersions in terms of the mean curvatures. We give a description of the two-umbilical isometric immersions in space forms which includes the product of spheres $S^{k}(\frac{1}{\sqr

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6

ROTH, JULIEN. "A NEW RESULT ABOUT ALMOST UMBILICAL HYPERSURFACES OF REAL SPACE FORMS." Bulletin of the Australian Mathematical Society 91, no. 1 (2014): 145–54. http://dx.doi.org/10.1017/s0004972714000732.

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AbstractIn this short note, we prove that an almost umbilical compact hypersurface of a real space form with almost Codazzi umbilicity tensor is embedded, diffeomorphic and quasi-isometric to a round sphere. Then, we derive a new characterisation of geodesic spheres in space forms.

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7

Cheng, Jih-Hsin, Hung-Lin Chiu, Jenn-Fang Hwang, and Paul Yang. "Umbilicity and characterization of Pansu spheres in the Heisenberg group." Journal für die reine und angewandte Mathematik (Crelles Journal) 2018, no. 738 (2018): 203–35. http://dx.doi.org/10.1515/crelle-2015-0044.

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Abstract For every {n\geq 2} we define a notion of umbilicity for hypersurfaces in the Heisenberg group {H_{n}} . We classify umbilic hypersurfaces in some cases, and prove that Pansu spheres are the only umbilic spheres with positive constant p-mean (or horizontal-mean) curvature in {H_{n}} up to Heisenberg translations.

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8

AQUINO, C. P., M. BATISTA, and H. F. DE LIMA. "ON THE UMBILICITY OF HYPERSURFACES IN THE HYPERBOLIC SPACE." Journal of the Australian Mathematical Society 103, no. 1 (2016): 45–58. http://dx.doi.org/10.1017/s1446788716000549.

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In this paper, we establish new characterization results concerning totally umbilical hypersurfaces of the hyperbolic space$\mathbb{H}^{n+1}$, under suitable constraints on the behavior of the Lorentzian Gauss map of complete hypersurfaces having some constant higher order mean curvature. Furthermore, working with different warped product models for$\mathbb{H}^{n+1}$and supposing that certain natural inequalities involving two consecutive higher order mean curvature functions are satisfied, we study the rigidity and the nonexistence of complete hypersurfaces immersed in$\mathbb{H}^{n+1}$.

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9

Romero-Fuster, Marı́a del Carmen, and Federico Sánchez-Bringas. "Umbilicity of surfaces with orthogonal asymptotic lines in R4." Differential Geometry and its Applications 16, no. 3 (2002): 213–24. http://dx.doi.org/10.1016/s0926-2245(02)00068-2.

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10

Bezerra, A. C., and F. Manfio. "Umbilicity of constant mean curvature hypersurfaces into space forms." Journal of Mathematical Analysis and Applications 537, no. 2 (2024): 128316. http://dx.doi.org/10.1016/j.jmaa.2024.128316.

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11

Moraes, S. M., M. C. Romero-Fuster, and F. Sánchez-Bringas. "Principal configurations and umbilicity of submanifolds in $\mathbb R^N$." Bulletin of the Belgian Mathematical Society - Simon Stevin 11, no. 2 (2004): 227–45. http://dx.doi.org/10.36045/bbms/1086969314.

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12

Aquino, Cícero P., and Henrique F. de Lima. "On the umbilicity of complete constant mean curvature spacelike hypersurfaces." Mathematische Annalen 360, no. 3-4 (2014): 555–69. http://dx.doi.org/10.1007/s00208-014-1049-z.

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13

Xie, Xun, Jiancheng Liu, and Chao Yang. "Complete CSC Hypersurfaces Satisfying an Okumura-Type Inequality in Ricci Symmetric Manifolds." Mathematics 9, no. 22 (2021): 2914. http://dx.doi.org/10.3390/math9222914.

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We investigate the spacelike hypersurface with constant scalar curvature (SCS) immersed in a Ricci symmetric manifold obeying standard curvature constraints. By supposing these hypersurfaces satisfy a suitable Okumura-type inequality recently introduced by Meléndez, which is a weaker hypothesis than to assume that they have two distinct principal curvatures, we obtain a series of umbilicity and pinching results. In particular, when the Ricci symmetric manifold is an Einstein manifold, then we further obtain some rigidity classifications of such hypersufaces.

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14

Agarwal, Richa, Fatemah Mofarreh, Sarvesh Kumar Yadav, Shahid Ali, and Abdul Haseeb. "On Riemannian warped-twisted product submersions." AIMS Mathematics 9, no. 2 (2024): 2925–37. http://dx.doi.org/10.3934/math.2024144.

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<abstract><p>In this paper, we introduce the concepts of Riemannian warped-twisted product submersions and examine their fundamental properties, including total geodesicity, total umbilicity and minimality. Additionally, we investigate the Ricci tensor of Riemannian warped-twisted product submersions, specifically about the horizontal and vertical distributions. Finally, we obtain Einstein condition for base manifold if the horizontal and vertical distributions of the ambient manifold is Einstein.</p></abstract>

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15

Bayard, Pierre, and Federico Sánchez-Bringas. "Invariants and quasi-umbilicity of timelike surfaces in Minkowski space R3,1." Journal of Geometry and Physics 62, no. 7 (2012): 1697–713. http://dx.doi.org/10.1016/j.geomphys.2012.03.008.

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16

Deszcz, Ryszard, Miroslava Petrovic-Torgasev, Zerrin Şentürk, and Leopold Verstraelen. "Characterization of the pseudo-symmetries of ideal Wintgen submanifolds of dimension 3." Publications de l'Institut Math?matique (Belgrade) 88, no. 102 (2010): 53–65. http://dx.doi.org/10.2298/pim1002053d.

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Recently, Choi and Lu proved that the Wintgen inequality ? ? H2??? +k, (where ? is the normalized scalar curvature and H2, respectively ??, are the squared mean curvature and the normalized scalar normal curvature) holds on any 3-dimensional submanifold M3 with arbitrary codimension m in any real space form ~M3+m(k) of curvature k. For a given Riemannian manifold M3, this inequality can be interpreted as follows: for all possible isometric immersions of M3 in space forms ~M3+m(k), the value of the intrinsic curvature ? of M puts a lower bound to all possible values of the extrinsic curvature H

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17

Alías, Luis J., Aldir Brasil, and A. Gervasio Colares. "INTEGRAL FORMULAE FOR SPACELIKE HYPERSURFACES IN CONFORMALLY STATIONARY SPACETIMES AND APPLICATIONS." Proceedings of the Edinburgh Mathematical Society 46, no. 2 (2003): 465–88. http://dx.doi.org/10.1017/s0013091502000500.

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AbstractIn this paper we develop general Minkowski-type formulae for compact spacelike hypersurfaces immersed into conformally stationary spacetimes, that is, Lorentzian manifolds admitting a timelike conformal field. We apply them to the study of the umbilicity of compact spacelike hypersurfaces in terms of their $r$-mean curvatures. We derive several uniqueness results, for instance, compact spacelike hypersurfaces are umbilical if either some of their $r$-mean curvatures are linearly related or one of them is constant.AMS 2000 Mathematics subject classification: Primary 53C42. Secondary 53B

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18

Grosjean, J. F., and J. Roth. "Eigenvalue pinching and application to the stability and the almost umbilicity of hypersurfaces." Mathematische Zeitschrift 271, no. 1-2 (2011): 469–88. http://dx.doi.org/10.1007/s00209-011-0872-0.

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19

Aquino, Cícero P., Márcio Batista, and Henrique F. de Lima. "On the umbilicity of generalized linear Weingarten spacelike hypersurfaces in a Lorentzian space form." Journal of Geometry and Physics 137 (March 2019): 228–36. http://dx.doi.org/10.1016/j.geomphys.2018.12.006.

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20

de Lima, Henrique F., Fábio R. dos Santos, and Marco A. L. Velásquez. "On the umbilicity of complete linear Weingarten spacelike hypersurfaces immersed in a locally symmetric Lorentz space." São Paulo Journal of Mathematical Sciences 11, no. 2 (2017): 456–70. http://dx.doi.org/10.1007/s40863-017-0075-7.

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21

Mi, Rong. "Characterizations of linear Weingarten space-like hypersurface in a locally symmetric Lorentz space." Mathematica Slovaca 69, no. 6 (2019): 1437–46. http://dx.doi.org/10.1515/ms-2017-0320.

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Abstract Our purpose in this paper is to study complete linear Weingarten space-like hypersurface immersed in locally symmetric Lorentz space obeying some curvature conditions. Our approach is based on the use of a Simons type formula related to an appropriated Cheng-Yau modified operator jointly with some generalized maximum principles, we obtain that such a space-like hypersurface must be either totally umbilical or isometric to an isoparametric hypersurface with two distinct principal curvatures, one of which is simple. This result corresponds to a natural improvement of previous ones due t

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22

ERTZ, Damien, Ulrik SØCHTING, Alice GADEA, Maryvonne CHARRIER, and Roar S. POULSEN. "Ducatina umbilicata gen. et sp. nov., a remarkable Trapeliaceae from the subantarctic islands in the Indian Ocean." Lichenologist 49, no. 2 (2017): 127–40. http://dx.doi.org/10.1017/s0024282916000700.

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AbstractThe new genus and species Ducatina umbilicata is described from Îles Crozet and Îles Kerguelen. This lichen is characterized by an umbilicate thallus with a black verrucose lower surface and a greyish to dark olivaceous smooth upper surface having large verrucae, large semi-immersed cephalodia, semi-immersed apothecia with a prominent thalline margin, simple, mainly ellipsoid ascospores of 23–42×12–25 µm and the presence of unknown chemical compounds. Phylogenetic analyses using nuLSU and mtSSU sequences place Ducatina in the Trapeliaceae (Baeomycetales). The new taxon is closely relat

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23

HOSEN, MD IQBAL, TAI-HUI LI, F. M. AMINUZZAMAN, and MD RAFIQUL ISLAM. "Hygrocybe umbilicata sp. nov., with first generic report for Bangladesh and its phylogenetic placement." Phytotaxa 280, no. 1 (2016): 70. http://dx.doi.org/10.11646/phytotaxa.280.1.7.

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Hygrocybe umbilicata, a new waxcap of Hygrophoraceae, is formally described from Bangladesh based on morphological data and molecular evidence of the nuclear ribosomal internal transcribed spacer (ITS) region. This species represents the first record of the genus Hygrocybe for this country. It can be easily recognized by its brilliantly scarlet red with umbilicate pileus, lemon yellow stipe, white short decurrent and distant lamellae, subglobose basidiospores, and abundant clamp connections in tissues. This species belongs to genus Hygrocybe subg. Pseudohygrocybe sect. Coccineae subsect. Squam

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24

T., TSHIKUNA-MATAMBA. "A Note on Riemannian Submersions with Umbilical Fibres." Journal of Progressive Research in Mathematics 6, no. 2 (2016): 778–84. https://doi.org/10.5281/zenodo.3977521.

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In this paper, we discuss some geometric properties of Riemannian submersions whose fibres are totally contact umbilical. Some interrelations between totally contact umbilic, totally geodesic and minimality are established.

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25

Kumar, S., B. S. Bhandari, and A. Falswal. "Peltula Shalae (Peltulaceae): A New Lichen Species from the Chenab Valley of Jammu and Kashmir, India." Acta Botanica Hungarica 66, no. 3-4 (2024): 225–31. https://doi.org/10.1556/034.66.2024.3-4.6.

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Peltula shalae Kumar S. is described as a new species of lichens from the Chenab Valley of Jammu and Kashmir, India. It is characterised by peltate-umbilicate thallus comprising of overlapping squamules forming rosettes, with diameter 2–3.5 cm. The absence of soredia is notable. This lichen is observed to grow on ‘shale rock’, a type of sedimentary rock, and is distinguished from closely related species, including P. daurica, P. sonorensis, P. anthracina, and P. obscurans by its distinct morphological features. Furthermore, a comprehensive comparison with closely related peltate-umbilicate spe

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26

LEE, GAIK EE, JULIA BECHTELER, and JOCHEN HEINRICHS. "A revision of unrevised taxon names in the former genus Taxilejeunea (Marchantiophyta: Lejeuneaceae) from Asia." Phytotaxa 358, no. 1 (2018): 26. http://dx.doi.org/10.11646/phytotaxa.358.1.2.

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Recent molecular work has shown that the genus Taxilejeunea is a synonym of Lejeunea. This study deals with the status of unrevised taxon names in Taxilejeunea from Asia. Six species are transferred to Lejeunea (L. compressiuscula, L. javanensis, L. koordersii, L. giulianettii, L. splendida, L. tjibodensis) and two new varieties, L. discreta var. gracilipes, L. pulchriflora var. nymannii, are described. Seven new synonyms are proposed: Taxilejeunea cuspidata Steph. ex Schiffn. [= L. stevensiana (Steph.) Mizut.], T. deflexa Steph. [= L. microloba Taylor], T. laxiretis (Steph.) Eifrig [= L. sord

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27

Arup, U., and M. Grube. "Is Rhizoplaca (Lecanorales, lichenized Ascomycota) a monophyletic genus?" Canadian Journal of Botany 78, no. 3 (2000): 318–27. http://dx.doi.org/10.1139/b00-006.

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Rhizoplaca Zopf is a genus characterized by an umbilicate thallus with an upper and a lower cortex, as well as a cupulate hypothecium. It has been considered to be related to Lecanora Ach., the type genus of the Lecanoraceae and, in particular, to the lobate species of this genus. The phylogeny of Rhizoplaca, the monotypic Arctopeltis thuleana Poelt, and a number of representatives of different groups of Lecanora is studied, using sequences from the nuclear ribosomal internal transcribed spacer (ITS) regions. The results suggest an origin for Rhizoplaca species within the large genus Lecanora.

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28

KANAMARU, Hiroshi, Naoki ISHIZUKA, and Yoshiaki HORIE. "Umbilicitis caused by Abdominal Wall Infection after Appendectomy." Nihon Gekakei Rengo Gakkaishi (Journal of Japanese College of Surgeons) 30, no. 6 (2005): 890–93. http://dx.doi.org/10.4030/jjcs1979.30.6_890.

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29

Fahselt, Dianne. "UV Absorbance By Thallus Extracts of Umbilicate Lichens." Lichenologist 25, no. 04 (1993): 415. http://dx.doi.org/10.1017/s0024282993000489.

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30

Hestmark, Geir. "Growth from the Centre in an Umbilicate Lichen." Lichenologist 29, no. 04 (1997): 379. http://dx.doi.org/10.1017/s0024282997000431.

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31

Hestmark, Geir. "Competitive behaviour of umbilicate lichens - an experimental approach." Oecologia 111, no. 4 (1997): 523–28. http://dx.doi.org/10.1007/s004420050266.

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32

Fahselt, Dianne. "UV Absorbance By Thallus Extracts of Umbilicate Lichens." Lichenologist 25, no. 4 (1993): 415–22. http://dx.doi.org/10.1006/lich.1993.1005.

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AbstractEleven stands of umbilicate lichens exhibiting a range of variabilities in enzyme banding patterns were compared on the basis of the ultraviolet (UV)absorbing properties of thallus extracts. Stands of Umbilicaria veilea, which were some of the most variable enzymatically, had the lowest UV absorbancy in extracts, and stands of Lasallia papulosa, which were among the least variable enzymatically, showed more UV absorbance than others. Umbilicaria deusta, U. muhlenbergii and U. mammulata had intermediate levels of absorbance. Negative correlations (P = 005–007) were found between enzyme

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33

Hestmark, Geir. "Growth from the Centre in an Umbilicate Lichen." Lichenologist 29, no. 4 (1997): 379–83. http://dx.doi.org/10.1006/lich.1997.0088.

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AbstractThe pustules on the surface of the umbilicate lichen Lasallia pustulata are moved away from the centre and towards the thallus margins with an average speed of 1.8 mm per year, revealing a growth pattern organized radially and flowing from the centre of the thallus. Pustules close to the margin move substantially faster than those close to the centre; for each 10 mm added to the initial distance from the centre, the speed of outward movement is about doubled. This suggests that intercalary growth over the entire thallus is displaced outwards in an accumulating manner, accelerating the

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34

Wang, Chun-xiao, Chuan-Feng Zheng, and Zun-Tian Zhao. "New records of Acarospora and Psora from China." Mycotaxon 134, no. 3 (2019): 535–43. http://dx.doi.org/10.5248/134.535.

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Acarospora impressula, A. umbilicata, Psora gresinonis, and P. himalayana are reported for the first time from China and Psora decipiens for the first time from Qinghai Province. Descriptions, illustrations, and distributions are given for each species.

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35

Martínez-Ortí, Alberto, Benjamín J. Gómez-Moliner, and Carlos E. Prieto. "El género Pyramidula Fitzinger 1833 (Gastropoda, Pulmonata) en la Península Ibérica." Iberus 25(1) (June 30, 2007): 77–87. https://doi.org/10.5281/zenodo.4532889.

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The geographical distribution of the <em>Pyramidula </em>species from the Iberian Peninsula has been reviewed. We characterize the shell parameters that allow the identification of Iberian species: <em>P. jaenensis</em>, <em>P. pusilla</em>, <em>P. rupestris </em>and <em>P. umbilicata</em>. The presence of the latter three species is confirmed for the Iberian Peninsula. The distribution maps obtained show that <em>P. pusilla </em>and <em>P. rupestris </em>are two species inhabiting the Pyrenees, Cantabrian region, Iberian System and east and south of the Iberian Peninsula, with <em>P. pusilla

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36

SEAPY, ROGER R. "A taxonomic review of janthinid gastropod molluscs from California Current Waters off the west coast of North America." Zoosymposia 13, no. 1 (2019): 151–53. http://dx.doi.org/10.11646/zoosymposia.13.1.16.

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Taxonomic characterization of janthinid gastropods, morphological characteristics, oceanic habitat and occurrence in coastal waters off the west coast of North America are reviewed. The two species (Janthina umbilicata and J. janthina) recorded from west coast waters are described and their shell morphologies illustrated.

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37

Falniowski, Andrzej, and Magdalena Szarowska. "Phylogenetic position of Boleana umbilicata (Kuščer, 1932) (Caenogastropoda: Rissooidea)." Folia Malacologica 20, no. 4 (2012): 265–70. http://dx.doi.org/10.2478/v10125-012-0022-2.

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38

Hale, M. E. "Xanthomaculina Hale, A New Lichen Genus in the Parmeliaceae (Ascomycotina)." Lichenologist 17, no. 3 (1985): 255–65. http://dx.doi.org/10.1017/s0024282985000329.

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AbstractThe endemic African lichen Parmelia hottentotta (Ach.) Ach. and related species are placed in a new genus, Xanthomaculina Hale, on the basis of cortical chemistry and a combination of conidial and morphological characters, including umbilicate growth form, presence of cilia and a vaulted cortex.

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39

Xiao, Ying-Qun, Hai-Jiao Li, Sai-Nan Li, Zuo-Hong Chen, Ping Zhang, and Zheng-Mi He. "Spodocybe umbilicata (Hygrophoraceae, Agaricales), a newly discovered species from subtropical China." Phytotaxa 620, no. 4 (2023): 273–82. https://doi.org/10.11646/phytotaxa.620.4.3.

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Xiao, Ying-Qun, Li, Hai-Jiao, Li, Sai-Nan, Chen, Zuo-Hong, Zhang, Ping, He, Zheng-Mi (2023): Spodocybe umbilicata (Hygrophoraceae, Agaricales), a newly discovered species from subtropical China. Phytotaxa 620 (4): 273-282, DOI: 10.11646/phytotaxa.620.4.3, URL: http://dx.doi.org/10.11646/phytotaxa.620.4.3

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40

SANDERS, William B., and Asunción DE LOS RíOS. "Structural evidence of diffuse growth and parenchymatous cell division in the cortex of the umbilicate lichen Lasallia pustulata." Lichenologist 50, no. 5 (2018): 583–90. http://dx.doi.org/10.1017/s0024282918000336.

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AbstractHow growth is distributed within the morphologically diverse thalli of lichens is still poorly known and the anatomical mechanisms involved are not well understood. This work applies electron microscopy (SEM and TEM) to examine cell- and tissue-level events in the umbilicate thallus of Lasallia pustulata, whose pattern of expansion was the subject of a previous field study. Stacks of epinecral tissue accumulating at the thallus surface showed broadening bases and recurring rupture attributable to diffuse expansion of the living tissue below. Cortical cells, dividing anticlinally, adjoi

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41

Büdel, Burkhard, and Thomas H. Nash. "A New Species of Peltula from the Sonoran Desert, Mexico." Lichenologist 25, no. 3 (1993): 279–84. http://dx.doi.org/10.1006/lich.1993.1032.

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AbstractThe new species Peltula sonorensis is described from the Sonoran Desert. It is found in several localities throughout the Mexican part of the Sonoran Desert and belongs to a distinct group within the genus Peltula, which is characterized by fairly large (up to 15 mm diam.), umbilicate-peltate squamules, growing individually and having ellipsoid to bacilliform spores.

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42

Nash III, Thomas H., Josef Hafellner, and Ralph S. Common. "Omphalora, A New Genus in the Parmeliaceae." Lichenologist 22, no. 4 (1990): 355–65. http://dx.doi.org/10.1017/s002428299000041x.

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AbstractThe status of four umbilicate lichens with lecanorine apothecia and hyaline, 1-celled ascospores is reviewed. It is concluded that Omphalodium should be emended to exclude O. arizonicum and consequently a new genus Omphalora T. Nash & Hafellner is proposed. Differences in anatomy, morphology, pseudocyphellae type, pigmentation and cell wall chemistry, and ascal dehiscence provide the primary justification for the new genus.

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43

VANDENBROUCKE, THIJS R. A., BARRIE RICKARDS, and JACQUES VERNIERS. "Upper Ordovician chitinozoan biostratigraphy from the type Ashgill area (Cautley district) and the Pus Gill section (Dufton district, Cross Fell Inlier), Cumbria, Northern England." Geological Magazine 142, no. 6 (2005): 783–807. http://dx.doi.org/10.1017/s0016756805000944.

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Seventy-five samples from the classic sections through the historical type area of the Ashgill Series in the Cautley district and along Pus Gill in the Cross Fell Inlier have been examined for chitinozoans. The results of this study allowed the recognition of five internationally recognized biozones and the definition of two new Avalonian chitinozoan zones. From bottom upwards, these are: the Fungochitina spinifera, the Tanuchitina bergstroemi?, the Conochitina rugata, the Spinachitina fossensis, the Bursachitina umbilicata sp. n., the Ancyrochitina merga and the Belonechitina postrobusta zone

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Reiner-Drehwald, María Elena, and Uwe Drehwald. "Sphaerolejeunea umbilicata (Lejeuneaceae): A Critically Endangered Epiphyllous Liverwort of the Andes." Bryologist 105, no. 3 (2002): 422–30. http://dx.doi.org/10.1639/0007-2745(2002)105[0422:sulace]2.0.co;2.

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WEI, YU-MEI, BOON-CHUAN HO, and QI-MING TANG. "Eulejeunea crenulata Schiffn., a new synonym of Lejeunea umbilicata (Lejeuneaceae, Marchantiophyta)." Phytotaxa 406, no. 1 (2019): 79. http://dx.doi.org/10.11646/phytotaxa.406.1.5.

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Stephani (1915) proposed the transfer of Eulejeunea crenulata Schiffner (1890: 33) to Lejeunea Libert (1820: 373). However, as the combination already existed and thus not available for use, Lejeunea crenulata (Schiffn.) Stephani (1915: 784) is a later homonym of Lejeunea crenulata Mitten (1871: 415). Nonetheless, Eulejeunea crenulata remains a validly published name (Söderström et al. 2015). According to the recent compilation of species binomials in Lejeuneaceae published between 1884 and 1893 (Söderström et al. 2015), Eulejeunea crenulata is listed as a heterotypic synonym of Lejeunea pater

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XIAO, YING-QUN, HAI-JIAO LI, SAI-NAN LI, ZUO-HONG CHEN, PING ZHANG, and ZHENG-MI HE. "Spodocybe umbilicata (Hygrophoraceae, Agaricales), a newly discovered species from subtropical China." Phytotaxa 620, no. 4 (2023): 273–82. http://dx.doi.org/10.11646/phytotaxa.620.4.3.

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Spodocybe is a recently established genus with many potential species yet to be discovered. The present study reports a new species of Spodocybe collected from subtropical China, whose delimitation is supported by both morphological and phylogenetic evidence. The species is characterized by its small umbilicate pileus with a greyish brown, finely felty surface, white decurrent lamellae, finely fibrillose stipe concolorous with the pileal surface, and elongate to cylindrical basidiospores measuring 6.0–9.0 × 3.0–4.5 μm. In addition, a worldwide key to the known Spodocybe species is provided.

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Revilla, Tx, and J. Gastón. "Nuevas aportaciones a la fauna de Microlepidoptera de España y otras citas de interés (Insecta: Lepidoptera)." SHILAP Revista de lepidopterología 47, no. 185 (2019): 57–64. http://dx.doi.org/10.57065/shilap.731.

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Se presentan nuevos registros para España de Bucculatricidae, Gracillariidae, Yponomeutidae, Glyphipterigidae, Blastobasidae, Gelechiidae y Pyralidae. Bucculatrix chrysanthemella Rebel, 1896, Parectopa robiniella Clemens, 1863, Yponomeuta irrorella (Hübner, 1796), Glyphipterix umbilici Hering, 1927 y Blastobasis decolorella (Wollaston, 1858) son nuevas para España. Se dan nuevas citas provinciales para Carpatolechia intermediella Huemer & Karsholt, 1999 y Pseudacrobasis tergestella (Ragonot, 1901).

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SHIMIZU, Akira, and Takuya KUBO. "Relationship between thallus size and apothecium density in two alpine umbilicate lichens." Lichenologist 41, no. 3 (2009): 285–97. http://dx.doi.org/10.1017/s0024282909007762.

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AbstractThe relationship between thallus size and apothecium density was studied in two umbilicate lichens, Umbilicaria cylindrica and Lasallia pensylvanica, growing in alpine rock surface environments. Samples of the two lichens were collected from the Daisetsuzan National Park, northern Japan. Umbilicaria cylindrica produced many smaller apothecia, whereas L. pensylvanica had larger but fewer apothecia. To explain the differences in reproductive efforts between these two species, we analyzed the lichen data using a hierarchical Bayesian model in which the density of apothecia for each specie

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ZHAO, QI, YAN-JIA HAO, JIAN-KUI LIU, et al. "Infundibulicybe rufa sp. nov. (Tricholomataceae), a reddish brown species from southwestern China." Phytotaxa 266, no. 2 (2016): 134. http://dx.doi.org/10.11646/phytotaxa.266.2.7.

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Infundibulicybe rufa sp. nov., is described from Jiuzhaigou Biosphere Reserve, southwestern China. It is characterized by the combination of the following characters: umbilicate to slightly infundibuliform, reddish brown pileus; decurrent, cream lamellae; cylindrical stipe concolorous with the pileus surface. Molecular phylogenetic analyses using the nuclear ribosomal internal transcribed spacer (ITS) region indicates that I. rufa is closely related to I. mediterranea and I. bresadolana. A description, line drawings, phylogenetic placement and comparison with allied taxa for the new taxon are

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Knudsen, K., A. Tsurykau, E. Hodková, V. Golubkov, P. Bely, and J. Kocourková. " ACAROSPORA FUSCATA AND A. UMBILICATA (ACAROSPORACEAE, ASCOMYCOTA) IN BELARUS." Ботанический журнал 107, no. 1 (2022): 38–46. http://dx.doi.org/10.31857/s0006813622010057.

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