Search

International audience; A new Gomphosphenia species (Bacillariophyceae) was found during a diatom survey in the “Réserve Naturelle Nationale de la Vallée de Chaudefour” (RNN VC), in the Massif Central (France). Gomphosphenia vallei sp. nov. is described from stone surfaces in Pérouse Stream, Auvergne, France. A detailed description of morphology of G. vallei is presented, based on light and scanning electron microscopy. This new small-sized species is characterized by linear-clavate to elliptical valves. Striae are uniseriate and composed of single slit-like areolae, an axial area linear and narrow and a low number of striae. Gomphosphenia vallei seems to inhabit headwater stream.

Gomphosphenia vallei Beauger, C.E.Wetzel, Allain & Ector sp. nov. (Figs 2 –45) Light microscopy observations (Figs 2–25): Valves linear-clavate in larger specimens to clavate in smaller ones and elliptical in the smallest individuals. Headpoles rounded, footpoles narrowly rounded. Valve dimensions (n = 30): length 4.2–13.1 µm, width 1.5–2.5 µm. Raphe straight, filiform. Striae visible in LM, almost parallel throughout the valve to slightly radiate in the mid-valve, 23–29 in 10 µm. Axial area linear and narrow. Central area from absent to asymmetrical with round and distinct central nodule. In girdle view, frustules almost rectangular to slightly wedgeshaped. Scanning electron microscopy observations (Figs 26–33): Valve face flat. Externally, striae composed of single slit-like areolae, becoming very short slit near the poles (Figs 26–30). Striae slightly radiate in central part of valve, becoming convergent towards both head and footpoles. Raphe straight, filiform, with slightly dilated distal and proximal raphe endings (Figs 26–30). Distal raphe fissures terminating on the valve face, not extending onto the valve mantle (Fig. 28). Internally, proximal raphe endings bent in the same direction (Fig. 31). Internal terminal raphe fissures ending in helictoglossae (Fig. 31). Single row of slit-like areolae located on the valve mantle (Figs 26, 28, 30, 32), sometimes rounded in shape near the mid-valve and towards the footpole (Figs 27, 33). Central area with a unilateral fascia, with a short areola on one side and absence of areola on the other side (Figs 26–29). Central nodule slightly raised (Fig. 31). Apical pore fields absent (Fig. 28). In girdle view, frustules with cingulum composed of open bands, each bearing one row of small round pores (Figs 28, 30, 32–33). Type locality: — FRANCE. Chambon-sur-Lac, “Réserve Naturelle Nationale de la Vallée de Chaudefour”: Pérouse Stream, sample PER _200821, 1,184 m a.s.l., E688534.487, N6493049.143 (Lambert 93), collection date 20 August 2021 (assigned here, holotype: CLF!, slide no. CLF310234; isotype: BR! slide no. BR-4707. The holotype is represented by Fig. 12). Etymology: — This species is named for Eric Vallé, curator of the National Nature Reserve and passionate about botany. Ecology and associated diatom taxa: — The Pérouse Stream, situated in the glacial cirque of Chaudefour Valley, is characterized by a low conductivity (35 μS cm-1), a low temperature (11.9 °C) and is well oxygenated (92.9% of dissolved oxygen) (Table 1). The pH is 7.09. As underlined the conductivity, the concentrations of the measured ions are low with a maximum for the sodium concentration (2.53 mg L- 1). The type population of G. vallei was found in Pérouse Stream associated with other taxa. In August 2021, the two co-dominant taxa were Planothidium lanceolatum (Brébisson ex Kützing 1846: 247) Lange-Bertalot (1999: 287) (36%) and Rhoicosphenia abbreviata (C. Agardh 1831: 34) Lange-Bertalot (1980: 586) (30%). The other species well represented (Achnanthidium subatomus (Hustedt 1939: 554) Lange-Bertalot (1999: 273) (7.1%), Gomphonema sp. cf. minutum C. Agardh (1831: 34) (6.4%), Navicula reichardtiana Lange-Bertalot in Lange-Bertalot & Krammer (1989: 163) (2.3%), Odontidium mesodon (Ehrenberg 1839: 57) Kützing (1849: 12) (2.3%), Gomphosphenia vallei (2.3%), Reimeria sinuata (W. Gregory 1856: 4) Kociolek & Stoermer (1987: 457) (1.9%), Planothidium curtistriatum C.E.Wetzel, Van de Vijver & Ector in Wetzel et al. (2019: 61) (1.9%), Cocconeis rouxii Héribaud & Brun in Héribaud (1893: 45) (1.9%) and Encyonema minutum (Hilse in Rabenhorst 1862: No. 1261) D.G.Mann in Round et al. (1990: 667) (1.1%). At last, Chamaepinnularia obsoleta (Hustedt 1942a: 69) C.E.Wetzel & Ector in Wetzel et al. (2013: 158), Cyclotella antiqua W. Smith (1853: 28), Geissleria acceptata (Hustedt 1950: 398) Lange-Bertalot & Metzeltin (1996: 64), Gomphonema clavatum Ehrenberg (1832: 88), Gomphonema exilissimum (Grunow in Van Heurck 1880: pl. 25, fig. 12) Lange-Bertalot & E.Reichardt in Lange-Bertalot & Metzeltin (1996: 70), Humidophila perpusilla (Grunow 1860: 552) R.L.Lowe, Kociolek, J.R.Johansen, Van de Vijver, Lange-Bertalot & Kopalová (2014: 358), Mayamaea permitis (Hustedt 1945: 919) Bruder & Medlin (2008: 327), Meridion constrictum Ralfs (1843: 458), Nitzschia hantzschiana Rabenhorst (1860: 40), Nitzschia soratensis E.Morales & M.L.Vis (2007: 128), Nupela lapidosa (Krasske 1929: 350) Lange-Bertalot (1999: 274), Pantocsekiella ocellata (Pantocsek 1901: 134) K.T.Kiss & Ács in Ács et al. (2016: 62), Pinnularia sinistra Krammer (1992: 105), Psammothidium helveticum (Hustedt 1933: 385) Bukhtiyarova & Round (1996: 8), Psammothidium subatomoides (Hustedt in Schmidt 1936: pl. 404) Bukhtiyarova & Round (1996: 13) and Sellaphora atomoides (Grunow in Van Heurck 1880: 107) C.E.Wetzel & Van de Vijver in Wetzel et al. (2015: 219) represented less than 1% of the whole community., Published as part of Beauger, Aude, Allain, Elisabeth, Voldoire, Olivier, Blavignac, Christelle, Rossi, Sofia, Wetzel, Carlos E. & Ector, Luc, 2022, Gomphosphenia vallei (Bacillariophyta), a new diatom species from a stream in the " Réserve Naturelle Nationale de la Vallée de Chaudefour ", Massif Central (France), pp. 167-179 in Phytotaxa 542 (2) on pages 170-173, DOI: 10.11646/phytotaxa.542.2.4, http://zenodo.org/record/6415941, {"references":["Kociolek, J. P., Laslandes, B., Bennett, D., Thomas, E., Brady, M. & Graeff, C. (2014) Diatoms of the United States, 1 Taxonomy, ultrastructure and descriptions of new species and other rarely reported taxa from lake sediments in the western U. S. A. Bibliotheca Diatomologica 61: 1 - 188.","Thomas, E. W., Kociolek, J. P., Lowe, R. L. & Johansen, J. R. (2009) Taxonomy, ultrastructure and distribution of gomphonemoid diatoms (Bacillariophyceae) from Great Smoky Mountains National Park (U. S. A.). Diatom taxonomy, ultrastructure and ecology: modern methods and timeless questions. A tribute to Eugene F. Stoermer. Nova Hedwigia, Beiheft 135: 201 - 237.","Kutzing, F. T. (1846) Kurze Mittheilung uber einige kieselschalige Diatomeen. Botanischen Zeitung 4: 247 - 248.","Lange-Bertalot, H. (1999) Neue Kombinationen von Taxa aus Achnanthes Bory (sensu lato). Iconographia Diatomologica 6: 276 - 289.","Agardh, C. A. (1831) Conspectus criticus diatomacearum. Part 3. Lundae Literis Berlingianus: 33 - 48.","Lange-Bertalot, H. (1980) Ein Beitrag zur Revision der Gattungen Rhoicosphenia Grun., Gomphonema C. Ag., Gomphoneis Cl. Botaniska Notiser 133: 585 - 594.","Hustedt, F. (1939) Die Diatomeenflora des Kustengebietes der Nordsee vom Dollart bis zur Elbemundung. I. Die Diatomeenflora in den Sedimenten der unteren Ems sowie auf den Watten in der Leybucht, des Memmert und bei der Insel Juist. Adhandlungen des Naturwissenschaftlichen Verein zu Bremen 31 (2 / 3): 571 - 677, 123 figs.","Ehrenberg, C. G. (1839) Uber das im Jahre 1686 in Curland vom Himmel gefallene Meteorpapier und uber dessen Zusammensetzung aus Conferven und Infusorien. Abhandlungen der Koniglichen Akademie der Wissenschaften zu Berlin 1838: 45 - 58.","Kutzing, F. T. (1849) Species Algarum. F. A. Brockhaus, Lipsiae [Leipzig], 922 pp. http: // dx. doi. org / 10.5962 / bhl. title. 60464","Gregory, W. (1856) Notice of some new species of British freshwater Diatomaceae. Quarterly Journal of Microscopical Science, New Series 4: 1 - 14.","Kociolek, J. P. & Stoermer, E. F. (1987) Ultrastructure of Cymbella sinuata and its allies (Bacillariophyceae), and their transfer to Reimeria, gen. nov. Systematic Botany 12 (4): 451 - 459. https: // doi. org / 10.2307 / 2418882","Wetzel, C. E., Van de Vijver, B., Blanco, S. & Ector, L. (2019) On some common and new cavum-bearing Planothidium (Bacillariophyta) species from freshwater. Fottea 19 (1): 50 - 89. https: // doi. org / 10.5507 / fot. 2018.016","Heribaud, J. (1893) Les Diatomees d'Auvergne. Pensionnat des Freres des Ecoles Chretiennes, Clermont-Ferrand & Librairie des Sciences Naturelles, Paris, 255 pp., 6 pls.","Rabenhorst, L. (1862) Die Algen Europa's, Fortsetzung der Algen Sachsens, Resp. Mittel-Europa's, Dresden. Decas, 25 - 26, nos 641 - 660.","Round, F. E., Crawford, R. M. & Mann, D. G. (1990) The diatoms: biology & morphology of the genera. Cambridge University Press, Cambridge, 747 pp.","Hustedt, F. (1942 a) Susswasser-Diatomeen des indomalayischen Archipels und der Hawaii-Inslen. Internationale Revue der gesamten Hydrobiologie und Hydrographie 42 (1 / 3): 1 - 252.","Wetzel, C. E., Martinez-Carreras, N., Hlubikova, D., Hoffmann, L., Pfister, L. & Ector, L. (2013) New combinations and type analysis of Chamaepinnularia species (Bacillariophyceae) from aerial habitats. Cryptogamie, Algologie 34 (2): 149 - 168. http: // dx. doi. org / 10.7872 / crya. v 34. iss 2.2013.149","Smith, W. (1853) A synopsis of the British Diatomaceae; with remarks on their structure, function and distribution; and instructions for collecting and preserving specimens. The plates by Tuffen West. In two volumes. London: John van Voorst, Paternoster Row, 33 pp.","Hustedt, F. (1950) Die Diatomeenflora norddeutscher Seen mit besonderer Berucksichtigung des holsteinischen Seengebiets. V - VII. Seen in Mecklenburg, Lauenburg und Nordostdeutschland. Archiv fur Hydrobiologie 43: 329 - 458.","Lange-Bertalot, H. & Metzeltin, D. (1996) Oligotrophie-Indikatoren. 800 Taxa reprasentativ fur drei diverse Seen-Typen. Kalkreich - Oligodystroph - Schwach gepuffertes Weichwasser [Indicators of oligotrophy. 800 taxa representative of three ecologically distinct lake types. Carbonate buffered - Oligodystrophic - Weakly buffered soft water]. Iconographia Diatomologica 2: 1 - 390.","Ehrenberg, C. G. (1832) Uber die Entwickelung und Lebensdauer der Infusionsthiere; nebst ferneren Beitragen zu einer Vergleichung ihrer organischen Systeme. Abhandlungen der Koniglichen Akademie Wissenschaften zu Berlin, Physikalische Klasse 1831: 1 - 154.","Van Heurck, H. (1880) Synopsis des Diatomees de Belgique Atlas. Ducaju et Cie, Anvers, pl. 1 - 30.","Grunow, A. (1860) Uber neue oder ungenugend gekannte Algen. Erste Folge, Diatomeen, Familie Naviculaceen. Verhandlungen der Kaiserlich-Koniglichen Zoologisch-Botanischen Gesellschaft in Wien 10: 503 - 582, pl. III - VII.","Hustedt, F. (1945) Diatomeen aus Seen und Quellgebieten der Balkan-Halbinsel. Archiv fur Hydrobiologie 40 (4): 867 - 973.","Bruder, K. & Medlin, L. K. (2008) Morphological and molecular investigations of naviculoid diatoms. II. Selected genera and families. Diatom Research 23 (2): 283 - 329. https: // doi. org / 10.1080 / 0269249 X. 2008.9705759","Ralfs, J. (1843) On the British species of Meridion and Gomphonema. Annals and Magazine of Natural History 12: 457 - 467.","Rabenhorst, L. (1860) Erklarung der Tafel VI. Hedwigia 2: 40, 6 / 6.","Krasske, G. (1929) Beitrage zur Kenntnis der Diatomeenflora Sachsens. Botanisches Archiv 27 (3 - 4): 347 - 380, 1 pl.","Pantocsek, J. (1901 ' 1902 ') A Balaton kovamoszatai vagy Bacillariai. A Balaton tudomanyos tanulmanyozasanak eredmenyei. Hornyansky Konyvnyomdaja, Budapest, 143 pp., 17 pls.","Acs, E., Ari, E., Duleba, M., Dressler, M., Genkal, S. I., Jako, E., Rimet, F., Ector, L. & Kiss, K. T. (2016) Pantocsekiella, a new centric diatom genus based on morphological and genetic studies. Fottea 16 (1): 56 - 78. https: // doi. org / 10.5507 / fot. 2015.028","Krammer, K. (1992) Pinnularia. Eine Monographie der europaischen Taxa. Bibliotheca Diatomologica 26: 1 - 353.","Hustedt, F. (1933) Die Kieselalgen Deutschlands, Osterreichs und der Schweiz unter Berucksichtigung der ubrigen Lander Europas sowie der angrenzenden Meeresgebiete. In: Rabenhorst, L. (Eds.) Kryptogamen Flora von Deutschland, Osterreich und der Schweiz. Akademische Verlagsgesellschaft m. b. h. Leipzig 7 (Teil 2, Lief. 3): 321 - 432.","Bukhtiyarova, L. & Round, F. E. (1996) Revision of the genus Achnanthes sensu lato Psammothidium, a new genus based on A. marginulatum. Diatom Research 11 (1): 1 - 30. https: // doi. org / 10.1080 / 0269249 X. 1996.9705361","Schmidt, A. (1936) Atlas der Diatomaceen-kunde. Leipzig. O. R. Reisland, Series VIII (Heft 101 - 102): pls. 401 - 408.","Wetzel, C. E., Ector, L., Van de Vijver, B., Compere, P. & Mann, D. G. (2015) Morphology, typification and critical analysis of some ecologically important small naviculoid species (Bacillariophyta). Fottea 15 (2): 203 - 234. https: // doi. org / 10.5507 / fot. 2015.020"]}

En la actualidad, la demanda de una sociedad global cada vez mas consciente de la escasez de recursos naturales ha orientado su vision al estimulo del desarrollo de tecnologias apropiadas para hacer mas eficiente el consumo de la energia. Esta idea nos hace plantearnos ciertas inquietudes, en base a los vacios que existen en la forma de construir en Venezuela y la situacion energetica, pues es evidente en el panorama actual, la crisis electrica que sufre el pais ademas de la carencia de normativas y regulaciones para el diseno de edificaciones de caracter educativo, que contemplen aspectos que favorezcan a mejores condiciones de confort y al menor consumo de energia. En tal sentido, el objetivo principal de esta investigacion es el estudio de una edificacion escolar, ubicada en la region andina de Venezuela, por medio del analisis del confort termico de los ocupantes en la edificacion, con el fin de determinar si el diseno de una tipologia constructiva de escuelas en el pais, ayudan a que los indices de confort termico de los ocupantes se encuentren en rangos aceptables. La metodologia aplicada para este analisis se basa en la aproximacion de resultados a traves de simulaciones por ordenador, obteniendo resultados de dinamica de fluidos computacional (CFD). Estos ultimos predicen el movimiento de fluidos, pudiendo definirse temperaturas e indices de confort termico (especificamente aquellos establecidos por Povl Ole Fanger), para los dias criticos de la estacion seca (verano) y la estacion lluviosa (invierno) en Venezuela. Los resultados de la simulacion muestran que existe mayor insatisfaccion termica durante la temporada de lluvia en gran parte de los espacios que conforman la escuela y que, la aplicacion de pequenas estrategias arquitectonicas de mejora, a su vez contribuyen a una mejora de las condiciones de confort en un 11 % durante la temporada lluviosa y un 7 % en relacion a la condicion de un ambiente totalmente cerrado durante la temporada seca.