Phytotaxa 167 (2): 215–216 www.mapress.com / phytotaxa / Copyright © 2014 Magnolia Press ISSN 1179-3155 (print edition) Correspondence PHYTOTAXA ISSN 1179-3163 (online edition) http://dx.doi.org/10.11646/phytotaxa.167.2.11 Notes on Early Land Plants Today. 52. Validation of Tritomaria camerunensis (Lophoziaceae, Marchantiophyta) JIŘÍ VÁŇA1, LARS SÖDERSTRÖM2,*, ANDERS HAGBORG3 & MATT VON KONRAT3 1 Department of Botany, Charles University, Benátská 2, CZ-12801 Praha 2, Czech Republic; email: vana@natur.cuni.cz Department of Biology, Norwegian University of Science and Technology, N-7491 Trondheim, Norway; lars.soderstrom@bio.ntnu.no 3 Department of Science and education, The Field Museum, 1400 South Lake Shore Drive, Chicago, IL 60605–2496, USA; hagborg@pobox.com, mvonkonrat@fieldmuseum.org * Author for correspondence 2 When describing Tritomaria camerunensis Arnell (1958: 64), Arnell based it on more than one gathering (Byström 35b and 50a) and it is thus invalid according to ICN Art. 40.2 (McNeill et al. 2012), a rule effective from 1 January 1958 saying that “indication of the type ... can be achieved by reference to an entire gathering” and Ex. 1 explicitly states that. This error was overlooked by Váňa (1982) who selected a “lectotype” out of Byström’s collection. However, that did not validate the name. In order to be available for the forthcoming world checklist of hornworts and liverworts (Söderström et al., in prep.) the taxon is here validated. As Arnell’s name is invalid, the description here is technically a new taxon. Schuster (1969: 639) did mention the close affinity to Tritomaria exsectiformis (Breidler 1894: 321) Loeske (1909: 13) “this may represent a disjunct phase of T. exsectiformis” but Váňa (1982) preferred to keep them separate until more material was studied. However, when the taxon needs to be validated, we prefer to do so at subspecific level. The new subspecies differs from. subsp. exsectiformis in larger size of plants (mostly 2–2.5 cm long vs. 1.2–2.0 cm long), constantly prostrate, never ascending shoots, dorsally secund, mostly bilobed leaves (trilobed leaves rare, only on the top of shoots), somewhat smaller and longer cells (up to 20 × 30–40 μm) than is the average cells size of Tritomaria exsectiformis subsp. exsectiformis, and rounded, angular to polygonal, 1–2–celled (vs. constantly 2–celled, irregularly polygonal to pyriform) gemmae. After 1982 the first author has had the opportunity to check two additional specimens of this taxon from Africa (Tanzania, Kilimanjaro Mt, S- and SW-face of Kibo, 4.3.1985 Pócs 6992/Q and 26.11.1989 Pócs 89240/B; EGR!, PRC!). Moreover, two very similar new species, Tritomaria mexicana (Bakalin 2008: 162), (isotypes in GOET! and PRC!) and Tritomaria koreana (Bakalin et al. 2009: 163) were recently described. Comparing the morphological differences between Tritomaria exsectiformis subsp. exsectiformis, Tritomaria exsectiformis subsp. arctica Schuster (1969: 661), Tritomaria camerunensis, Tritomaria mexicana and Tritomaria koreana we found that there are no significant differences in the size of plants, cell size, cell walls [thick cell walls given for Tritomaria camerunensis is an error based on the cells of the intermixed plants of Sphenolobus minutus (Crantz 1770: 285) Berggren (1898: 22), cf. Váňa 1982], trigones and cell surface (cuticle), size and shape of oilbodies (if the data are available). The orientation of shoots (prostrate or ascending to erect) and the orientation and insertion of leaves (spreading to erect-spreading, with transversely to subtransversely insertion vs. dorsally secund, with subtransversely to oblique insertion) may be caused by the habitat conditions. Some differences are only in the leaf shape and gemmae, as follows: Tritomaria exsectiformis subsp. exsectiformis:—leaves asymmetrically (2–)3–lobed, longer than wide, ovate; gemmae polygonal to pyriform, 2–celled, (13–) 14–18 (–20) × (16–) 17–26 μm, red brown. Tritomaria exsectiformis subsp. arctica:—leaves asymmetrically 2–3–lobed, wider than long, broadly orbicular; gemmae tetrahedral to polygonal, 2–celled, 9.5–14 (–16) × 11–18.5 (–20) μm, reddish to reddish brown. Tritomaria exsectiformis subsp. camerunensis:—leaves in upper parts of shoots asymmetrically bilobed, only terminal leaves of most developed shoots asymmetrically trilobed, longer than wide, ovate; gemmae rounded angular to polygonal, 1–2 celled, 14 × 14–22 μm, red brown. Accepted by Christine Cargill: 28 Feb. 2014; published: 9 May 2014 Licensed under a Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0 215 Tritomaria mexicana:—leaves mostly equally (!) to slightly asymmetrically bilobed, longer than wide, ovate; gemmae angular, 1–celled, 18–23 × 20–26 μm, rusty red to blackish purple. Tritomaria koreana:—leaves slightly asymmetrically bilobed, longer than wide, ovate; gemmae angular, 1–celled, 10–12.5 × 12.5–15 μm, green to greenish white. All three taxa, Tritomaria exsectiformis subsp. camerunensis, Tritomaria mexicana and Tritomaria koreana, are geographically separated from Tritomaria exsectiformis with Tritomaria exsectiformis subsp. arctica representing the high Arctic phase of the species. Until more material of these taxa is available (the last two species are known only from the type specimens) and a population based molecular study undertaken, we prefer to keep them as separate species. Formal treatment The format of this note follows Söderström et al. (2012). Tritomaria exsectiformis Breidl. subsp. camerunensis S.W.Arnell ex Váňa, subsp. nov. Based on:—Tritomaria camerunensis S.W.Arnell, Svensk Bot. Tidskr. 52: 64, 1958 (Arnell 1958), nom. inval. (ICN Art. 40.2; based on more than one gathering). Type:—CAMEROON. Cameroon Mountain, summit region, Byström no. 35b (UPS!, holotype), Byström 50a (UPS!, syntype). Note:—The reference to the description in Arnell (1958: 64), together with the reference to the single gathering here, validates the taxon. Acknowledgements The Early Land Plants Today project (ELPT) has been generously supported in part by the Global Biological Information Facility (GBIF) Seed Money Award No.2007-41, activities facilitated in part by funding from the Biodiversity Synthesis Center of the Encyclopedia of Life (BioSynC), partial funding from the National Science Foundation (Award No's 0749762, 1115002), the Warwick Foundation and the Negaunee Foundation. References Arnell, S.W. (1958) New Hepaticae from Cameroon Mountain. Svensk Botanisk Tidskrift 52: 63–67. Bakalin, V.A. (2008) New data on distribution and taxonomy of some species in Lophoziaceae (Hepaticae). Arctoa 17: 161–164. Bakalin, V. A., Choi, S.-S. & Sun, B.-Y. (2009) A new species of Tritomaria (Lophoziaceae) from the Korean peninsula. Arctoa 18: 163–166. Berggren, S. (1898) On New Zealand Hepaticae. I. E. Malmström, Lund, 48 pp. Breidler, J. (1894) Die Lebermoose Steiermarks. Mitteilungen des Naturwissenschaftlichen Vereines für Steiermark 30: 256–357. Crantz, D. (1770) Fortsättning af historien om Grönland. Johan Georg Lange, Stockholm, 380 pp. Loeske, L. (1909) Zur Moosflora der Zillertaler Alpen. Hedwigia 49: 1–53. McNeill, J., Barrie, F.R., Buck, W.R., Demoulin, V., Greuter, W., Hawksworth, D.L., Herendeen, P.S., Knapp, S., Marhold, K., Prado, J., Prud'homme van Reine, W.F., Smith, G.F., Wiersema, J.H. & Turland, N.J. (2012) International Code of Nomenclature for algae, fungi and plants (Melbourne Code) adopted by the Eighteenth International Botanical Congress Melbourne, Australia, July 2011. Regnum Vegetabile 154: 1–240. Schuster, R.M. (1969) The Hepaticae and Anthocerotae of North America. II. Columbia University Press, New York, 1062 pp. Söderström, L., Hagborg, A. & von Konrat, M. (2012) Notes on Early Land Plants Today. Phytotaxa 65: 41–42. Váňa, J. (1982) Notes on some African hepatic genera 1–5. Folia Geobotanica et Phytotaxonomica 17: 63–87. 216 • Phytotaxa 167 (2) © 2014 Magnolia Press VÁŇA ET AL.