Abstract
The new liverwort species Chiastocaulon raetzelii is described from New Caledonia. Chiastocaulon raetzelii is characterized by very fragile, caducous leaves, stems therefore often becoming completely denuded of leaves; only bract leaves of the androecia are permanent and often the only ones remaining on the stem. Plants are minute with leafy shoots to 1 mm wide. Leaves on leafy shoots are arranged in opposing pairs, they are obovate-truncate to spathulate, with 3–7 teeth per leaf, teeth are filiform, consisting of long rectangular cells, and occupy about 1/3 to 1/4 of the entire leaf length. The species is compared to C. oppositum and C. geminifolium, which are the most similar morphologically.
References
<p>Bescherelle, É. (1873) Florule bryologique de la Nouvelle-Calédonie. <em>Annales des Sciences Naturelles; Botanique, sér. 5, </em>18: 184–245.</p>
<p>Carl, H. (1931) Morphologische Studien an <em>Chiastocaulon</em> Carl, einer neuen Lebermoosgattung. <em>Flora</em> 126: 45–60. https://doi.org/10.1016/S0367-1615(17)31155-2</p>
<p>De Notaris, G. (1874) <em>Epatiche di Borneo raccolte dal dre O. Beccari nel ragiato di Sarawak durante gli anni 1865-66-67</em>. Stamperia reale di G. P. Paravia, Torino, 86 pp.</p>
<p>Dugas, M. (1928) <em>Contribution à l’étude du genre “Plagiochila” Dum. </em>Thèse, Faculté de Sciences, Université de Paris (ser. A, n. 1170), 199 pp.</p>
<p>Dugas, M. (1929) Contribution à l’étude du genre “<em>Plagiochila</em>” Dum. <em>Annales des sciences naturelles, botanique, ser. 10</em>, 11: 1–199.</p>
<p>Grolle, R. (1995) The Hepaticae and Anthocerotae of the East African islands: an annotated catalogue. <em>Bryophytorum Bibliotheca</em> 48: 1–178.</p>
<p>Hattori, S. (1947) Five new genera of Hepaticae. <em>Biosphaera</em> 1: 3–7.</p>
<p>Herzog, T. (1950) Hepaticae Borneenses (Oxford University Expedition to Sarawak. 1932). With introductory ecological notes by P.W. Richards. <em>Transactions of the British Bryological Society</em> 1: 275–326. https://doi.org/10.1179/006813850804878680</p>
<p>Inoue, H. (1964) The genus <em>Plagiochilion</em>. <em>Journal of the Hattori Botanical Laboratory</em> 27: 51–72.</p>
<p>Kitagawa, N. (1972) Notes on little-known species of Hepaticae, 1–25. <em>Journal of the Hattori Botanical Laboratory</em> 36: 444–454.</p>
<p>Lindberg, S.O. (1869) Nya mossor. <em>Öfversigt af Finska Vetenskaps-Societetens Förhandlingar</em> 12 (2): 70–84.</p>
<p>Lindberg, S.O. & Lackström, E.F. (1874) <em>Hepaticae Scandinavicae exsiccata quarum specimina, fasc. 1</em>. 25 pp.</p>
<p>Mitten, W. (1861) Musci et Hepaticae Vitienses. <em>Bonplandia (Hannover)</em> 9: 365–367.</p>
<p>Mitten, W. (1871) Ordo CIX. Jungermanniae. <em>In: </em>Seemann, B.C. (Ed.) <em>Flora Vitiensis</em>. L. Reeve and Co., London, pp. 404–419.</p>
<p>Nees von Esenbeck, C.G.D. (1830) <em>Enumeratio Plantarum Cryptogamicarum Javae et insularum adjacentium etc. Fasciculus prior Hepaticas complectens</em>. Sumtibus Grassii, Barthii et Soc., Vratislaviae [Breslau], 86 pp.</p>
<p>Paris, E.G. (1910) Hépatiques de Nouvelle-Calédonie (3e art.). <em>Revue bryologique </em>37: 128–132.</p>
<p>Patzak, S.D., Renner, M.A.M., Schäfer-Verwimp, A., Feldberg, K., Heslewood, M.M., Peralta, D.F., de Souza, A.M., Schneider, H. & Heinrichs, J. (2016) A phylogeny of Lophocoleaceae-Plagiochilaceae-Brevianthaceae and a revised classification of Plagiochilaceae. <em>Organisms Diversity Evolution</em> 16 (3): 481–495. https://doi.org/10.1007/s13127-015-0258-y</p>
<p>Reinwardt, C.G.C., Blume, C.L. & Nees von Esenbeck, C.G. (1824) Hepaticae Iavanicae. <em>Nova Acta Physico-medica Academiae Caesareae Leopoldino-Carolinae Naturae Curiosorum Exhibentia Ephemerides sive Observationes Historias et Experimenta</em> 12: 183–238.</p>
<p>Renner, M.A.M., Heslewood, M.M., Patzak, S.D.F., Schäfer-Verwimp, A. & Heinrichs, J. (2016) The genera <em>Chiastocaulon</em>, <em>Cryptoplagiochila</em> and <em>Pedinophyllum </em>(Plagiochilaceae) in Australia. <em>Australian Systematic Botany</em> 29: 358–402. https://doi.org/10.1071/SB16029</p>
<p>Renner, M.A.M. & Worboys, S. (2018) Two additional <em>Chiastocaulon</em> species (Marchatiophyta: Plagiochilaceae) from the Wet Tropics Bioregion of north-eastern Queensland. <em>Australian Systematic Botany</em> 31: 487–494. https://doi.org/10.1071/SB18014</p>
<p>Schiffner, V. (1900) <em>Die Hepaticae der Flora von Buitenzorg</em>, <em>Band 1.</em> E. J. Brill, Leiden, 220 pp.</p>
<p>Schiffner, V.F. (1910) Über die Gattungen <em>Chiloscyphus</em> und <em>Heteroscyphus</em> n. gen. <em>Oesterreichische Botanische Zeitschrift</em> 60 (5): 169–173. https://doi.org/10.1007/BF01631854</p>
<p>Schuster, R.M. (1963) Studies on antipodal Hepaticae. I. Annotated keys to the genera of antipodal Hepaticae with special reference to New Zealand and Tasmania. <em>Journal of the Hattori Botanical Laboratory</em> 26: 185–309.</p>
<p>Schuster, R.M. (1970) Studies on Antipodal Hepaticae, III. <em>Jubulopsis</em> Schuster, <em>Neohattoria</em> Kamimura and <em>Amphijubula</em> Schuster. <em>Journal of the Hattori Botanical Laboratory</em> 33: 266–304.</p>
<p>Schuster, R.M. (1992) <em>The Hepaticae and Anthocerotae of North America</em>. Vol. 5. Columbia University Press, New York, 854 pp.</p>
<p>Stephani, F. (1908) Hépatiques de la Nouvelle-Calédonie et du Tonkin. <em>Revue Bryologique</em> 35: 28–35.</p>
<p>Stephani, F. (1910) II. Hepaticae. pp. 193–201. <em>In</em>: Rechinger, K. (Ed.) Botanische und zoologische Ergebnisse einer wissenschaftlichen Forschungsreise nach den Samoainseln, dem Neuguinea-Archipel und den Salomonsinseln. III. Teil. <em>Denkschriften der Kaiserlichen Akademie der Wissenschaften, Wien. Mathematisch-naturwissenschaftliche Klasse</em> 85: 175–432.</p>
<p>Stephani, F. (1924) <em>Species Hepaticarum, Vol. 6</em>. Georg & Cie, Geneva, 762 pp.</p>
<p>Thouvenot, L., Gradstein, S.R., Hagborg, A., Söderström, L. & Bardat, J. (2011) Checklist of the liverworts and hornworts of New Caledonia. <em>Cryptogamie, Bryologie</em>, 32: 287–390. https://doi.org/10.7872/cryb.v32.iss4.2011.287</p>
<p>Váňa, J., Hentschel, J. & Heinrichs, J. (2010) New combinations in Jungermanniales: transfer of 32 taxa to <em>Solenostoma</em> Mitt. <em>Cryptogamie, Bryologie</em> 31 (2): 135–139.</p>
<p>Carl, H. (1931) Morphologische Studien an <em>Chiastocaulon</em> Carl, einer neuen Lebermoosgattung. <em>Flora</em> 126: 45–60. https://doi.org/10.1016/S0367-1615(17)31155-2</p>
<p>De Notaris, G. (1874) <em>Epatiche di Borneo raccolte dal dre O. Beccari nel ragiato di Sarawak durante gli anni 1865-66-67</em>. Stamperia reale di G. P. Paravia, Torino, 86 pp.</p>
<p>Dugas, M. (1928) <em>Contribution à l’étude du genre “Plagiochila” Dum. </em>Thèse, Faculté de Sciences, Université de Paris (ser. A, n. 1170), 199 pp.</p>
<p>Dugas, M. (1929) Contribution à l’étude du genre “<em>Plagiochila</em>” Dum. <em>Annales des sciences naturelles, botanique, ser. 10</em>, 11: 1–199.</p>
<p>Grolle, R. (1995) The Hepaticae and Anthocerotae of the East African islands: an annotated catalogue. <em>Bryophytorum Bibliotheca</em> 48: 1–178.</p>
<p>Hattori, S. (1947) Five new genera of Hepaticae. <em>Biosphaera</em> 1: 3–7.</p>
<p>Herzog, T. (1950) Hepaticae Borneenses (Oxford University Expedition to Sarawak. 1932). With introductory ecological notes by P.W. Richards. <em>Transactions of the British Bryological Society</em> 1: 275–326. https://doi.org/10.1179/006813850804878680</p>
<p>Inoue, H. (1964) The genus <em>Plagiochilion</em>. <em>Journal of the Hattori Botanical Laboratory</em> 27: 51–72.</p>
<p>Kitagawa, N. (1972) Notes on little-known species of Hepaticae, 1–25. <em>Journal of the Hattori Botanical Laboratory</em> 36: 444–454.</p>
<p>Lindberg, S.O. (1869) Nya mossor. <em>Öfversigt af Finska Vetenskaps-Societetens Förhandlingar</em> 12 (2): 70–84.</p>
<p>Lindberg, S.O. & Lackström, E.F. (1874) <em>Hepaticae Scandinavicae exsiccata quarum specimina, fasc. 1</em>. 25 pp.</p>
<p>Mitten, W. (1861) Musci et Hepaticae Vitienses. <em>Bonplandia (Hannover)</em> 9: 365–367.</p>
<p>Mitten, W. (1871) Ordo CIX. Jungermanniae. <em>In: </em>Seemann, B.C. (Ed.) <em>Flora Vitiensis</em>. L. Reeve and Co., London, pp. 404–419.</p>
<p>Nees von Esenbeck, C.G.D. (1830) <em>Enumeratio Plantarum Cryptogamicarum Javae et insularum adjacentium etc. Fasciculus prior Hepaticas complectens</em>. Sumtibus Grassii, Barthii et Soc., Vratislaviae [Breslau], 86 pp.</p>
<p>Paris, E.G. (1910) Hépatiques de Nouvelle-Calédonie (3e art.). <em>Revue bryologique </em>37: 128–132.</p>
<p>Patzak, S.D., Renner, M.A.M., Schäfer-Verwimp, A., Feldberg, K., Heslewood, M.M., Peralta, D.F., de Souza, A.M., Schneider, H. & Heinrichs, J. (2016) A phylogeny of Lophocoleaceae-Plagiochilaceae-Brevianthaceae and a revised classification of Plagiochilaceae. <em>Organisms Diversity Evolution</em> 16 (3): 481–495. https://doi.org/10.1007/s13127-015-0258-y</p>
<p>Reinwardt, C.G.C., Blume, C.L. & Nees von Esenbeck, C.G. (1824) Hepaticae Iavanicae. <em>Nova Acta Physico-medica Academiae Caesareae Leopoldino-Carolinae Naturae Curiosorum Exhibentia Ephemerides sive Observationes Historias et Experimenta</em> 12: 183–238.</p>
<p>Renner, M.A.M., Heslewood, M.M., Patzak, S.D.F., Schäfer-Verwimp, A. & Heinrichs, J. (2016) The genera <em>Chiastocaulon</em>, <em>Cryptoplagiochila</em> and <em>Pedinophyllum </em>(Plagiochilaceae) in Australia. <em>Australian Systematic Botany</em> 29: 358–402. https://doi.org/10.1071/SB16029</p>
<p>Renner, M.A.M. & Worboys, S. (2018) Two additional <em>Chiastocaulon</em> species (Marchatiophyta: Plagiochilaceae) from the Wet Tropics Bioregion of north-eastern Queensland. <em>Australian Systematic Botany</em> 31: 487–494. https://doi.org/10.1071/SB18014</p>
<p>Schiffner, V. (1900) <em>Die Hepaticae der Flora von Buitenzorg</em>, <em>Band 1.</em> E. J. Brill, Leiden, 220 pp.</p>
<p>Schiffner, V.F. (1910) Über die Gattungen <em>Chiloscyphus</em> und <em>Heteroscyphus</em> n. gen. <em>Oesterreichische Botanische Zeitschrift</em> 60 (5): 169–173. https://doi.org/10.1007/BF01631854</p>
<p>Schuster, R.M. (1963) Studies on antipodal Hepaticae. I. Annotated keys to the genera of antipodal Hepaticae with special reference to New Zealand and Tasmania. <em>Journal of the Hattori Botanical Laboratory</em> 26: 185–309.</p>
<p>Schuster, R.M. (1970) Studies on Antipodal Hepaticae, III. <em>Jubulopsis</em> Schuster, <em>Neohattoria</em> Kamimura and <em>Amphijubula</em> Schuster. <em>Journal of the Hattori Botanical Laboratory</em> 33: 266–304.</p>
<p>Schuster, R.M. (1992) <em>The Hepaticae and Anthocerotae of North America</em>. Vol. 5. Columbia University Press, New York, 854 pp.</p>
<p>Stephani, F. (1908) Hépatiques de la Nouvelle-Calédonie et du Tonkin. <em>Revue Bryologique</em> 35: 28–35.</p>
<p>Stephani, F. (1910) II. Hepaticae. pp. 193–201. <em>In</em>: Rechinger, K. (Ed.) Botanische und zoologische Ergebnisse einer wissenschaftlichen Forschungsreise nach den Samoainseln, dem Neuguinea-Archipel und den Salomonsinseln. III. Teil. <em>Denkschriften der Kaiserlichen Akademie der Wissenschaften, Wien. Mathematisch-naturwissenschaftliche Klasse</em> 85: 175–432.</p>
<p>Stephani, F. (1924) <em>Species Hepaticarum, Vol. 6</em>. Georg & Cie, Geneva, 762 pp.</p>
<p>Thouvenot, L., Gradstein, S.R., Hagborg, A., Söderström, L. & Bardat, J. (2011) Checklist of the liverworts and hornworts of New Caledonia. <em>Cryptogamie, Bryologie</em>, 32: 287–390. https://doi.org/10.7872/cryb.v32.iss4.2011.287</p>
<p>Váňa, J., Hentschel, J. & Heinrichs, J. (2010) New combinations in Jungermanniales: transfer of 32 taxa to <em>Solenostoma</em> Mitt. <em>Cryptogamie, Bryologie</em> 31 (2): 135–139.</p>