Plectocolea subbalfourii

Váňa, Jiří, Söderström, Lars, Hagborg, Anders & Konrat, Matt Von, 2013, Notes on Early Land Plants Today. 44. Comments on sexuality in Solenostoma (Solenostomataceae, Marchantiophyta) and on some newly described taxa, Phytotaxa 152 (1), pp. 33-47 : 41-42

Plectocolea subbalfourii

In the examination of the duplicate specimen of the type of Bakalin’s new species Plectocolea subbalfourii , received as a gift from T. Pócs by the senior author, only sterile plants were found, intermixed with plants of Marchantia and Riccardia . Recently the richer isotype specimen (Bakalin examined the smaller duplicate deposited in NY; moreover the first author have also a smaller duplicate) from the herbarium of Prof. T. Pócs (coll. Vojtkó/A,B,C; EGR) was received for re-examination. Between rhizoids of Marchantia one shoot with a perianth of “ Plectocolea ” - type was found. Based on this, the former identification by the senior author as Jungermannia borgenii Pearson (1892: 11) [= Solenostoma borgenii (Pearson) Stephani (1901: 493) ] must be corrected. Bakalin (2013: 129) compared the specimen with Solenostoma balfourii , which was described on the basis of very sparse and poorly developed plants also from NY herbarium. He does not mention if he examined the type of Solenostoma balfourii , but he apparently compared the plants with the original description. According to Bakalin the differences from Solenostoma balfourii are as follows: a) “a higher perigynium ca. 0.6–0.7 of perianth length (vs. 0.3–0.5 of perianth length in Solenostoma balfourii )”. One shoot with perianth found in EGR specimen has perigynium only ca. 0.4 of the perianth length (not 0.6–0.7 of the perianth length). b) “obliquely to erect spreading rhizoids, mostly not fasciculate (vs. forming more or less clear fascicles)”. The rhizoids in the original (EGR) and duplicate ( PRC) specimens sometimes (in the perianth bearing plant) form a decurrent fascicle, in the sterile shoots the fascicle is “less clear”. c) “not rhizogenous leaves (vs. rhizogenous)”. In the original description by Váňa (1974b: 280) rhizoids are mentioned as “von basalen Blatt- und Perigyniumzellen entspringend“ [originating from basal leaf and perigynium cells], which does not fully correspond to the term “rhizogenous leaves”. In the specimens examined the rhizoids originate also from basal leaf cells and perigynium cells as in original specimen. d) “larger midleaf cells, up to 70 × 57 Μm (vs. 28–35 Μm)”. In the original description (based on poorly developed plants) the marginal cells are 25–30 Μm, median ones 28–35 Μm and the basal ones 45–60 × 30–35 Μm. EGR and PRC specimens have the median cells a little bit larger (median cells 30–50 Μm, basal ones up to 65 Μm). In fact, the cells of well developed plants of Solenostoma balfourii are a little bit larger than in the type specimen. The larger cell size for the species was confirmed by the study of one additional specimen of this species known from Réunion (coll. Gimalac 75.R.963; herb. Onraedt). In addition, Bakalin (2013: fig. 2: 8, 9) does not show smooth cell surface although the description state “cuticle smooth”.

Solenostoma balfourii (Váňa) Váňa, Hentschel et Heinrichs, Cryptog. Bryol. 31: 136, 2010 (Váňa et al. 2010). Basionym: Jungermannia balfourii Váňa , Folia Geobot. Phytotax. 9(3): 279, 1974 ( Váňa 1974b). Type:— MAURITIUS, Balfour, det. Mitten as J. dusenii (holotype: NY-Mitten!)

= Plectocolea subbalfourii Bakalin, Polish Bot. J. 58: 129, 2013 ( Bakalin 2013), syn. nov. Type: REUNION. E edge of Cirque de Mafate , on rocky N slope of Plateau de La Sale, along path, 26 August 1994, A. Vojtkó 9429 (holotype NY 1717834 !, isotypes in EGR!, PRC!) .