Bazzania tridens Trevis.
Creators: name: Thouvenot, Louis
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Plantae
Marchantiophyta
Jungermanniopsida
Jungermanniales
Lepidoziaceae
Bazzania
Bazzania tridens

description: Bazzania tridens (Reinw., Blume & Nees) Trevis.
(Figs 2E, F; 15)
Memorie del Reale Istituto Lombardo de Scienze e Lettere, serie 3, Classe di Scienze Matematiche e Naturali 4: 415 (Trevisan 1877). — Jungermannia tridens Reinw., Blume & Nees, Nova Acta Physico-Medica Academiae Caesareae Leopoldino-Carolinae Naturae Curiosorum 12: 228 (Reinwardt et al. 1824).
— Type: Java, Blume; (iso-, G [G0064266]!) not seen.
Herpetium australe Mont., Annales des Sciences naturelles; Botanique, (sér. 2), 1: 254 (Montagne 1843). — Mastigobryum australe (Mont.) Lindenb., Synopsis hepaticarum (fasc. 2): 228 (Gottsche et al. 1845) [Gottsche, Lindenberg & Nees (1845)].
Bazzania australis (Mont.) Trevis., Memorie del Reale Istituto Lombardo de Scienze e Lettere, serie 3, Classe di Scienze Matematiche e Naturali 4: 415 (Trevisan 1877).
— Type: Fiji, Balaou, (lecto-, designated here fide Grolle (1986, in sched. “Holotypus”); PC [PC0769355]!).
Mastigobryum limbatum Steph., Species Hepaticarum 6: 472 (Stephani 1924). — Bazzania limbata (Steph.) Tixier., Bulletin du Muséum national d’Histoire naturelle, série 3, 10 (190): 77 (Tixier 1973). — Type: New Caledonia, Lerat; (lecto-, designated here: G[New Caledonia, ex herb. Paris, Le Rat 42 G00066868]!) syn. nov.
Mastigobryum subserrifolium Beauverd, Species Hepaticarum 6: 480 (Stephani 1924). — Bazzania subserrifolia (Beauverd) H.A.Mill., Phytologia 47: 321 (Miller 1981). — Type: New Caledonia, Lerat s.n. (not seen) syn. nov.
MATERIAL EXAMINED. — Java • ex herb. Nees, “original” (G [G00064266] as Mastigobryum tridens); Preanger Prov.; 11.II.1894; V. Schiffner s.n. (PC, s.n.).
New Caledonia • s.l., s.d.; Pancher s.n. ex hb. Bescherelle (G, s.n. as Bazzania ‘australe’) • South Province, La Foa, Mt Dogny; in the litter on the ground in forest on a ridge of sedimentary bed rock; 900 m; 23.IX.2008; Thouvenot NC578, NC599 • Dumbéa, Mt Koghis; on old trees; VIII.1905; Le Rat s.n. (herbarium E.G. Paris as Mastigobryum limbatum, REN [REN000221]) • ibid.; on bark in wet forest; 8.VIII.2014; Métoyer MET033 • ibid.; 8.IV.2013; Coulerie COU99.
DISTRIBUTION IN NEW CALEDONIA. — Hitherto only found in South Province, on bark and litter.
TOTAL RANGE. — South-East Asia (from India to Indonesia, Philippines, Japan) and New Caledonia. Also reported from Samoa, Fiji, Papua New Guinea (GBIF 2023).
DESCRIPTION
Plants
Medium sized, rigid, growing in wefts or creeping among other bryophytes,shoots 2(-3) mm wide,terminal branching common, pseudo-dichotomous, ventral-intercalary branches flagelliform.
Leaves
Imbricate, widely spreading at nearly right angle when moist, deflexed when dry, asymmetrically oblong to lingulate, usually falcate, (1.00-) 1.10-1.35 mm long, 0.60-0.85 mm wide near base, length to width ratio 1.5-1.8; dorsal margins widely arched in lower half, slightly convex to straight in upper part, ventral margins concave to nearly straight, shortly rounded at base, both margins crenulate to unevenly denticulate, mainly in upper half including apex; leaf apices obliquely truncate to rounded, shortly 3-dentate, teeth shortly triangular, usually 1-2 cells long, 1-2 cells at bases.
Areolation
Contrasted, median cells evenly thick-walled, trigones inconspicuous or lacking, hexagonal to oblong, 12-25 µm wide, marginal cells oblate; internal cells larger, 25-35 µm long, 16-25 µm wide, up to 40 µm wide and 60 µm long at insertion, thin-walled with acute trigones, forming a poor subvitta.
Underleaves
Plane,appressed,obliquely inserted,positioned near leaf insertion on both sides, shortly connate or not, quadrate-rounded, 0.50- 0.70 mm as wide as long, 1-2(-3) times wider than the stem; margins repand all around;cells hyaline,thin-walled, except in a small area at insertion; basal cells chlorophyllose, thick-walled, oblong to rectangular (Description after the type of Herpetium australe).
NOTES
Bazzania tridens was reported as Mastigobryum australe from New Caledonia by Stephani (1908c), based on a specimen collected by Pancher. It was successively reported byJovet-Ast (1951) and Thouvenot et al. (2011) without further reference. I examined the specimen Pancher kept at G (from the Bescherelle’s herbarium s.n.) and compared it to the holotype of Herpetium australe at PC. In the Pancher specimen, the underleaves have narrow hyaline margins, 3-4 cells wide, instead of being nearly entirely hyaline and median leaf cells have large bulging trigones whereas the leaf cells of H. australe lack them. Therefore, it cannot be that species; more likely it is Bazzania franciana. Fortunately, new collections have provided evidence for the presence of this species in New Caledonia.
As underlined by Meijer (1960), in the neighbouring islands of the type location (Java), the forms of B. tridens “differ by shorter, more blunt leaves and by amphigastria which are in their lower half not hyaline”. New Caledonian specimens match the main characters of B. tridens, allowing for the above variation highlighted by Meijer. They were described by Stephani under the name Mastigobryum limbatum. Kitagawa (1973) considered M. limbatum synonymous with Bazzania franciana, as did Meagher (2010), but in our opinion it differs from the latter by the almost entirely hyaline underleaves that are mainly free, the leaf margins faintly serrulate and the median leaf cells without trigones. These features are characteristic of B. tridens. The apices are shortly dentate as are those of B. australis, another synonym of B. tridens fide Grolle (1980).
Stephani described Mastigobryum subserrifolium as a new species from a specimen initially named M. serrifolium that did not fit the type of M. serrifolium Steph. (Stephani 1908c), nowadays synonymous with Bazzania bernieri.If Stephani expressly excluded the latter type as a reference for B. subserrifolia, in contrast, he did not clearly designate any type specimen for M. subserrifolium, and I was unable to find any original material labelled under the following new combination at G: “ Mastigobryum subserrifolium Bvrd. n. nov.= M.serrifolium Stephani mss., non in Sp.Hep. III [1908]484.” Furthermore, there is no corresponding illustration in Stephani’s Icones consulted at G. Stephani described M. subserrifolium from a specimen collected by Le Rat, likely sent by E.G.Paris (Stephani’s correspondence to E.G.Paris,unpublished manuscript [Rennes1 University Library]). I therefore looked for a potential type in the herbaria that usually house duplicates of Le Rat specimens distributed by Paris, firstly the E.G. Paris herbarium at REN, as well as G and PC. In these herbaria, I checked all specimens labelled M. serrifolium to look for a voucher that differed from B. bernieri and could therefore be a potential type for M. subserrifolium, as asserted by Stephani in the protologue. Unfortunately, all the specimens checked at G match the characters of Bazzania bernieri and do not fall within the original description of M.subserrifolium by Stephani,the only reference available.The main differences between these two species are the leaf shapes and underleaf hyaline margins as follows: M. subserrifolium: leaves oblong, asymmetrically sub-lingulate, and underleaf hyaline areolation well defined; M. serrifolium: leaves sub-symmetrically ovate and underleaf hyaline margins very narrow, usually eroded (character omitted in the diagnosis but conspicuous in the types).Conversely, the Stephani diagnosis fits the characters of B. tridens as described here above, the only notable differences are in the leaf and median cell sizes, but it is common that the measures given by Stephani are larger than those observed on the New Caledonian specimens of many species. Accordingly, I regard Bazzania subserrifolia as a synonym of B. tridens, but cautiously, pending finding a type specimen.
description: Published as part of Thouvenot, Louis, 2024, A revision of the genus Bazzania Gray (Lepidoziaceae, Marchantiophyta) in New Caledonia with a review of the type specimens, pp. 117-154 in Cryptogamie, Bryologie 20 (6) on pages 146-148, DOI: 10.5252/cryptogamie-bryologie2024v45a6, http://zenodo.org/record/14546400