Myriocoleopsis in Southeast Asia
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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/288334475 strong> Myriocoleopsis in Southeast Asia</strong Article in Bryophyte Diversity and Evolution · December 2010 DOI: 10.11646/bde.31.1.18 CITATIONS READS 11 71 1 author: Tamás Pócs Eszterházy Károly Egyetem 258 PUBLICATIONS 3,950 CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: Liverworts (Hepaticae) of the Selva Central region of Peruvian Andes. View project Bryophyte diversity in Polylepis forests View project All content following this page was uploaded by Tamás Pócs on 28 March 2016. The user has requested enhancement of the downloaded file. Tropical Bryology 31: 123-125, 2010 Myriocoleopsis in Southeast Asia Tamás Pócs Botany Department, Eszterházy College, Eger, Pf. 43, H-3301, Hungary ([email protected]) Abstract: A molecular investigation by Wilson et al. (2006) showing the close relationship between the neotropical Myricoleopsis gymnocolea (Spruce) Reiner & Gradst. and Cololejeunea vuquangensis Pócs & Ninh. from Vietnam, instigated the author to reexamine the latter species. The morphological and anatomical characters of Cololejeunea vuquangensis support its transfer to the genus Myriocoleopsis and the new combination of Myriocoleopsis vuquangensis (Pócs & Ninh) Pócs, comb. nov. is proposed. This is the first record of the South American genus Myriocoleopsis from Asia and a remarkable extension of its known distribution. Keywords: Cololejeunea, Lejeuneaceae, molecular phylogeny, morphology, Myriocoleopsis, rheophyte, stem anatomy, Vietnam. Introduction multicellular stem cortex. Schäfer-Verwimp and Vital (1989) reported many other localities of M. puiggarii Cololejeunea vuquangensis was described from the from a large area of south-eastern Brazil. Vu Quang Nature Reserve in central Vietnam near to the Laotian border, from a riparian habitat (Pócs & Reiner-Drehwald and Gradstein (1995) described a Ninh 2005). We described and illustrated in detail its second species, Myriocoleopsis riparia Reiner & morphological features, including its sporophyte, and Gradst., from south-eastern Brazil and from northern used these characters to separate the new species from Argentina, characterized by thin stems consisting of Cololejeunea minutissima (Smith) Schiffn. The one medullary cell and only 5 cortex cells. Thus, the distinguishing characters included, a.o., the peculiar generic concept of the genus was broadened. cushion-forming growth habit with creeping primary Surprisingly, all records of M. puiggarii reported by stems and erect, 3-5 mm long secondary stems, the Schäfer-Verwimp & Vital (1989) belonged to the new very numerous perianths and very long androecial species. Reiner-Drehwald and Gradstein (1995) also spikes (up to 3 mm length and 30 pairs of bracts). noted a confusingly close similarity of the new species to Cololejeunea (subgenus Protocolea) In a recent study on the molecular phylogeny of the minutissima subsp. myriocarpa (Nees. & Mont.) Lejeuneaceae, Wilson et al. (2006) showed that Schust., and proposed that the similarity of Cololejeunea vuquangensis was nested together with Myricoleopsis to Cololejeunea subgenus Myriocoleopsis gymnocolea in a clade different from Chlorolejeunea was a convergency resulting from the Cololejeunea. This prompted me to immediately periodically submersed, rheophytic habitat of these reexamine our species. Indeed, we have not realized two taxa. that most of the above-mentioned characters of Cololejeunea vuquangensis serve to separate the Two years later, new synonymies and combinations neotropical genus Myriocoleopsis from Cololejeunea were established for the two species of (subgenus Protocolea). Myriocoleopsis, viz. M. fluviatilis (Steph. ) Reiner & Gradst. for M. puiggarii (based on the earlier name Myriocoleopsis, with M. puiggari Schiffn. as its only Cololejeunea fluviatilis Steph.) and M. gymnocolea species, was described by Schiffner (1944) from (Spruce) Reiner & Gradst. for M. riparia, based on Brazil based on the collection made by J.I. Puiggari in Lejeunea gymnocolea Spruce collected by Richard 1873. A second locality, detected in 1973 by D.M. Spruce in Ecuador (for full synonymy see Reiner- Vital, was published together with a more detailed Drehwald and Gradstein 1997 and Gradstein & Costa description of the genus by Gradstein and Vital 2003). Recently, Myriocoleopsis gymnocolea has (1975). The latter authors proposed a close been recollected in Ecuador, the first record of the relationship of Myriocoleopsis to Cololejeunea species in that country since almost 150 years subgenus Chlorolejeunea Benedix based on the (Gradstein et al. 2004). TROPICAL BRYOLOGY 31 (2010) 124 PÓCS: MYRIOCOLEOPSIS IN SOUTHEAST ASIA the erect leafy stems arising from creeping stolons, the stem section with 5-9 cortical cells, the reduced leaf lobule, and the androecia with up to 30 pairs of bracts (Pócs & Ninh 2005). Cololejeunea vuquangensis lives as a rheophyte on the twigs of Homonoia riparia Lour., an euphorbiaceous shrub, which forms bush on the riverbed shoals (see Pócs & Ninh l.c. 166, fig. 55), which are inundated twice a year during monsoon periods (Thái văn Trừng 1970). The height of floods was well visible on the marks of the tree trunks in the riverine forest along the type locality. The erect leafy stems (Fig. 1) arising from stolons were well-figured by Pócs & Ninh (2005, Figs. 11-12) and closely Figure 1. The habit of Myriocoleopsis vuquangensis resemble those of Myriocoleopsis puiggarii illustrated (Pócs & Ninh) Pócs. The left bar indicates by Gradstein & Vital (1975, photo 1). The analysis of millimeters. the stem anatomy, which was not yet studied, shows that the creeping stem has 8-12 cortical cell rows in one outer and in a scattered inner layer and 1 Careful reexamination of Cololejeunea vuquangensis, medullary cell row (Fig. 2a), the primary, erect including analysis of the stem anatomy, shows that branches 7-9 cortical and 1 medullary cells (Fig. 2b), this species belongs to the genus Myriocoleopsis and the secondary branches, which bear the Schiffn. All characters of Myriocoleopsis listed by gametangia, 5 cortical and 1 medullary cells (Fig. 2c). Reiner-Drehwald & Gradstein (1995: 484) in their Although the leaf shape is in many aspects similar to synoptic table comparing Myriocoleopsis with that of Cololejeunea minutissima subsp. myriocarpa Cololejeunea, fit our species: the rheophytic habitat, (Nees. & Mont.) Schust., the leaves consist of much more cells (lobe width up to 30 cells), the keel is more widely rounded (Fig. 2d) and the lobule teeth are more reduced, becoming obsolete. The male branches are composed of 8-30 pairs of male bracts, resulting in a much longer male spike than in any species of Cololejeunea subg. Protocolea. The only character different from the two known Myriocoleopsis species is, that in all observed cases there was only one innovation below the gynoecium, resulting in a compound raceme, not in a cymose branching system. As in the other Myriocoleopsis species, perianths are very abundant produced and provided with five low, rounded keels and a short beak (see Figs. 2e, 3; Pócs & Ninh 2005: 166, figs. 14, 56 ). These characters justify the transfer of Cololejeunea vuquangensis Pócs & Ninh to the genus Myriocoleopsis Schiffn. This present view is convincingly supported by the above-mentioned molecular evidence. The following new combination is proposed: Myriocoleopsis vuquangensis (Pócs & Ninh) Pócs, comb. nov. Basionym: Cololejeunea vuquangensis Pócs & Ninh, Acta Bot. Hung. 47(1-2): 156 (2005). With this transfer the known distribution of Figure 2. Myriocoleopsis vuquangensis (Pócs & Ninh) Myriocoleopsis is extended from the Neotropics to Pócs. a: Cross section of the creeping stem (stolon). b: Paleotropics, enriching the Vietnamese liverwort flora Cross sections of the leafy, erect primary stems. c: by and interesting rheophytic element (Fig. 4). Cross section of a secondary branch. d: Cross section Myriocoleopsis vuquangensis grows only a few of the keel between lobe and lobule. e: Cross section hundred meters away from the locality of the of a perianth. rheophytic Cololejeunea (subgen. Chlorolejeunea) TROPICAL BRYOLOGY 31 (2010) PÓCS: MYRIOCOLEOPSIS IN SOUTHEAST ASIA 125 Acknowledgements. I acknowledge with thanks the financial support assured by ASEAN Biodiversity Program. Thanks are due also to Prof. Trân Ninh (State University of Hanoi) for initiating and organizing the collecting expedition and to Prof. Benito S. Tan (Singapore Botanic Garden) for participating in the collecting activities. References Benedix, E. H. 1953. Indomalayische Cololejeuneen. Feddes Repertorium, Beihefte 134: 1-88. Gradstein, S. R. & D. M. Vital. 1975. On Myricoleopsis Schiffn. (Lejeuneaceae). Lindbergia 3: 39-45. Gradstein, S. R. & D. P. Costa. 2003. The Hepaticae and Anthocerotae of Brazil. Memoirs of the New York Botanical Garden 87: 1-318. Gradstein, S. R., M. E. Reiner-Drehwald & L. Jost. Figure 3. The gynoecia of Myriocoleopsis 2004. The systematic position and distribution of vuquangensis (Pócs & Ninh) Pócs. (All pictures based Myriocolea irrorata (Lejeuneaceae, Hepaticae), an endangered liverwort from the Ecuadorian Andes. on the holotype). SEM photo made by Andrea Sass- Journal of the Hattori Botanical Laboratory 93: 235- Gyarmati. 248. Pócs, T. & Tran Ninh. 2005. Contribution to the bryoflora of Vietnam, VI. On the liverwort flora of Vu Quang Nature Reserve. Acta Botanica Hungarica