taxonID	type	description	language	source
A012AD30FFADFFACFF1A4C24595824FF.taxon	description	The complete series of 2 µm sections show the principally similar pattern in peristome development in four species of Encalypta. Selected photographs from these series were obtained for three samples of E. procera from two populations, two samples of E. longicollis from one population, four samples of E. rhaptocarpa from two localities and one sample of E. vulgaris; they are given in Figs. 2, 3, 5. The developmental stages show in these figures start either from the “ fundamential cross ” or from eight-cells pattern where four endothecial and four amphithecial cells are differentiated. Downwards to juvenile sporophyte, the successive series present patterns characterized by peristomial formulae: 1, 2: 1, 2: 2: 2, 4: 2: 2, with some deviations. Longitudinal sections available for some species indicate the position of respective transverse sections, calculated as the difference between given section and by first section where endothecium is seen, and multiplied by 2 µm (the thickness of sections). As the series might not cover the latest stages of peristomial development occurred, e. g., during sporogenesis time, we supplemented the series of transverse sections with SEM observations of inner (ventral) surface of basal parts of teeth. The occurrence of anticlinal divisions, albeit partly fairly irregular, indicates the delayed divisons in IPL cells of proximal part of teeth in all species of Encalypta. At the same time, middle, and moreover, distal parts of inner surface of teeth indicate that the formula 4: 2: 4 is performed only in proximal part of peristome, while more distally the formula remains to be 4: 2: 2. Species-specific characteristics are listed briefly for individual species, based on these few studied specimens.	en	Ignatov, Michael S., Spirina, Ulyana N., Kolesnikova, Maria A., Ashikhmina, Darya A., Ignatova, Elena A., Polevova, Svetlana V. (2018): Peristome development pattern in Encalypta poses a problem: what is the primary peristomial layer in mosses? Arctoa 27 (1): 1-17, DOI: 10.15298/arctoa.27.01, URL: https://doi.org/10.15298/arctoa.27.01
A012AD30FFADFFACFF1A490459DB21C7.taxon	description	This species is known as having the greatest number of layers among arthrodontous mosses. Some of them are obviously developed at the later stages during sporogenesis, as at the earlier stages used in the present analysis sequence of divisions results in pattern characterised by the following formulae: 2: 1 — 2: 2: 1 — 4: 4: 2: 2 — 4: 4: 4: 2: 2 — 8: 4: 4: 2: 2. The IPL: PPL cells thickness ratio is 1.4 – 2: 1. Anticlinal divisions occur at the later stages in few PPL cells (Fig. 3 G). In some sectors the peristomial formula comprises 4: 2: 3 pattern (Fig. 3 H), although this case was observed in only one series of sections. Various irregularities, including, e. g., anticlinal divisions in some PPL cells, are more numerous comapred to E. procera. Longitudinal sections (Figs. 3 A, B) illustrate less regular cell arrangement in E. longicollis compared to E. procera (Fig. 2 C). Multilayered peristome at its mature stage is shown in Fig. 4. It is formed of five layers with decomposed cell content only in outermost and innermost layers. Content of cells corresponding to PPL, OPL 1 and OPL 2 transforms into the fibrillose substance that fills them, without any tendency for sedimentation along cell walls (Figs. 4 D, F). Berberin staining of cell walls indicates the position of cellulose only at cell walls (Fig. 4 E), thus the substance filling the main volume of cells remains unknown.	en	Ignatov, Michael S., Spirina, Ulyana N., Kolesnikova, Maria A., Ashikhmina, Darya A., Ignatova, Elena A., Polevova, Svetlana V. (2018): Peristome development pattern in Encalypta poses a problem: what is the primary peristomial layer in mosses? Arctoa 27 (1): 1-17, DOI: 10.15298/arctoa.27.01, URL: https://doi.org/10.15298/arctoa.27.01
A012AD30FFADFFACFF1A48C4595C253F.taxon	description	The studied sequence of divisions results in a pattern characterised by the following formulae: 2: 1 — 2: 2: 2 — 4: 2: 2 — 8 - 4: 4: 2: 2. The IPL: PPL cells thickness ratio is ca. 2.5: 1. Few anticlinal divisions occur at the later stages of development in both IPL and PPL (Fig. 2: H, I, J).	en	Ignatov, Michael S., Spirina, Ulyana N., Kolesnikova, Maria A., Ashikhmina, Darya A., Ignatova, Elena A., Polevova, Svetlana V. (2018): Peristome development pattern in Encalypta poses a problem: what is the primary peristomial layer in mosses? Arctoa 27 (1): 1-17, DOI: 10.15298/arctoa.27.01, URL: https://doi.org/10.15298/arctoa.27.01
A012AD30FFADFFACFC904DEC5E8C27E7.taxon	description	The studied sequence of divisions results in a pattern characterised by the following formulae: 2: 1 — 2: 2: 1 — 4: 2: 2 — 8: 4: 2: 2 — 8: 4: 4: 2. The IPL: PPL cells thickness ratio varies from 3: 1 to 1.2: 1 in different series and at different stages. Anticlinal divisions are numerous at later stages of development in both IPL and PPL (Fig. 5 H, I), and occasionally periclinal divisions occur in IPL at the level of proximal part of teeth. In later (lower in the series) stages, cell walls from different layers are quite perfectly aligned, while in a medium stage, 4: 2: 2, the aligning is only moderately perfect, and in one sector 4: 2: 3 pattern is seen. Being solitary, it could be considered as an exception, however in another sector the cell wall is also quite offset (Fig. 5 E, arrowed).	en	Ignatov, Michael S., Spirina, Ulyana N., Kolesnikova, Maria A., Ashikhmina, Darya A., Ignatova, Elena A., Polevova, Svetlana V. (2018): Peristome development pattern in Encalypta poses a problem: what is the primary peristomial layer in mosses? Arctoa 27 (1): 1-17, DOI: 10.15298/arctoa.27.01, URL: https://doi.org/10.15298/arctoa.27.01
A012AD30FFADFFACFC904BCC59CD25C7.taxon	description	Available material for this species was imperfect. However, it is interesting, showing a great variation with numerous additional anticlinal divisions in both IPL and PPL, so the formulae 2: 1, 2: 2, and 4: 4: 4 were observed. The IPL: PPL cells thickness ratio varies even more than in E. rhaptocarpa, from 4: 1 to 1: 1 at different stages. * * * Structure of the IPL cells formed at the latest stages of development is seen in the SEM images of the lowermost parts of teeth from inside (Fig. 6), where each tooth has two cells on its surface. This allow conclusion that IPL cell divisions are delayed in Enclaypta, thus mostly not seen in series of transverse section (Figs. 2, 3, 5), however obviously happens later, thus the number of IPL cells in peristome formulae of Encalypta should be 4, not 2.	en	Ignatov, Michael S., Spirina, Ulyana N., Kolesnikova, Maria A., Ashikhmina, Darya A., Ignatova, Elena A., Polevova, Svetlana V. (2018): Peristome development pattern in Encalypta poses a problem: what is the primary peristomial layer in mosses? Arctoa 27 (1): 1-17, DOI: 10.15298/arctoa.27.01, URL: https://doi.org/10.15298/arctoa.27.01
A012AD30FFA7FFA2FF1A48065B9323E7.taxon	description	The studied sequence of divisions results in pattern characterised by the following formulae: 2: 1 (not shown) — 2: 2: 1 — 4: 2: 2 — 8: 4: 4: 4 (opposite). The IPL: PPL cells thickness ratio is 1.5 – 2: 1. Repeated anticlinal divisions occur at later stages of development in both IPL and PPL (Fig. 7 D, E, G). Cells of peristomial layers, as seen in longitudinal sections (Fig. 7 C), are more regularly arranged compared to Encalypta (Figs. 2 C, 3 A). Funaria arctica (Figs. 8, 9) As the genus Funaria has been already a subject of the peristome development studies, we display here mostly the later stages. Fig. 8 A shows the stage where some IPL cells are already underwent anticlinal divisions (corresponding to 4: 2: 4 formula), while some did not, thus fitting 4: 2: 2 formula, which is characteristic for earlier stage of development. IPL cells have divided periclinally at the level reached by sporogeneous tissue: darker cell content in the outermost endothecial layer is not yet discernible in Fig. 8 D, but becomes more or less apparent 10 µm below, at Fig. 8 E, F, and clearly seen further below, at Figs. 8 G, H. Note that the regular pattern of peristomial layers is still distinct at the level of urn, where sporogeneous tissue is apparent (Figs. 8, 9). For the present study it is important to note that Funaria differs from Encalypta and Timmia by a relatively better developed PPL, so the IPL: PPL cells thickness ratio is 0.8 – 1 (– 1.3): 1; the anticlinal divisions in PPL are absent, and cell walls in neighboring peristomial layers are always clearly aligned.	en	Ignatov, Michael S., Spirina, Ulyana N., Kolesnikova, Maria A., Ashikhmina, Darya A., Ignatova, Elena A., Polevova, Svetlana V. (2018): Peristome development pattern in Encalypta poses a problem: what is the primary peristomial layer in mosses? Arctoa 27 (1): 1-17, DOI: 10.15298/arctoa.27.01, URL: https://doi.org/10.15298/arctoa.27.01
