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Fossil floral assemblage from the Upper Triassic Grabowa Formation (Upper Silesia, southern Poland)165–193165–193

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Wawrzyniak Z. , Filipiak P.

Annales Societatis Geologorum Poloniae

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2023

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tom Vol. 93, No. 2

165--193

EN

Upper Triassic fossil plants are well documented from the Keuper of Europe. Carnian and Rhaetian floras are rich in a variety of plant taxa, whereas in comparison, the Norian is limited to a few localities with poorly preserved fossil plant communities showing low diversification. The Norian Grabowa Formation in Zawiercie-Marciszów, Upper Silesia, southern Poland, contains fossils of arborescent gymnosperms, including petrified conifer trunks. In this study, we present a fossil plant assemblage, containing fragmented plant parts in multiple forms of preservation, i.e., permineralised trunks and rooting structures, stems compressions, dispersed cuticles, and megaspores. Analysis of the macromorphological characters proved the presence of gymnosperms, including the ar-borescent conifer Agathoxylon cf. keuperianum, known already from this locality from fragments of charcoalified wood. Sphenophytes are represented by disarticulated stems of Equisetites sp., and Neocalamites sp. The variation in plant fossils indicates the possibility of higher plant diversity. Analysis of cuticles, macerated from different plant-bearing lithologies, revealed a variety of conifer foliage, expressed as five cuticulae dispersae morphotypes (needle-leaf Elatocladus-type and scale-leaf Pagio- Brachyphyllum-like). Plant fossils at Zawiercie-Marciszów are preserved in calcareous mudstones and micritic limestone concretions, developed in a fluvial environment. The presence of sphenophyte stems (Equisetites and Neocalamites) indicates that local conditions were more humid and suitable for spore-producing plants, appearing in the mid-Norian tectonic-pluvial episode, recorded in the Grabowa Fm.

2

Ovule, megaspores, and female gametophyte formation in Larix decidua Mill. [Pinaceae]

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Slobodnik B. , Guttenberger H.

Acta Biologica Cracoviensia. Series Botanica

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2000

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tom 42

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nr 2

EN

Compared to the formation of male generative organs, the development of female sporogenous tissue of the European larch (Larix decidua Mill.) is considerably delayed. The young megaspore mother cell (megasporocyte, MMC) is not observable until late October, a short time before the period of dormancy. In early spring, MMCs become moderately enlarged, with intensive accumulation of starch grains around the nucleus. At the end of the first 10 days of March the MMCs become more rounded in section and the nucleus moves towards the basal part of the cell (near the chalaza). The integument and nucellus become observable at that time and chromosomal strands are visible in the MMC nuclei. Meiosis of MMCs was observed from mid-March to early April. During that period the tip of the integument grows gradually over the nucellus and creates the stigmatic apparatus of the ovule. Instead of the expected tetrads, triads of linearly arranged unequal megaspores were observed in individual ovules at the beginning of pollen shedding. Immediately after meiosis of the MMC, massive growth of the functional chalazal megaspore occurs, along with intensive free-nuclear divisions. The nuclei become located near the megaspore membrane, whereas the whole central part of the developing female gametophyte is filled with an extraordinarily large central vacuole. During intensive growth of the functional megaspore, the innermost layer of the nucellar tapetum gradually disintegrates. This development stage lasts until early May, when the megaspore membrane segregates partially from the nucellar tapetum and the free-nucleate female gametophyte assumes an irregular sac-like shape. The cellular stage of the female gametophyte with typical pyramidal cells at its micropylar end is visible at mid-May. Then the vacuolated (so-called frothy) archegonia gradually forms. The disappearance of vacuoles and the division of the central cell were registered in late May. At the stage of the large female gamete (egg cell) and the small ventral canal cell, the archegonia become fully receptive for fertilization. Our observations indicate that the development of the free-nucleate gametophyte and the formation of cell walls among the nuclei are the most sensitive phases of ovule development in the European larch before fertilization. During these stages, numerous cases of degeneration of the female gametophyte were observed, along with the complete deformation of ovules. The reasons for frequent irregularities are discussed here; the influence of meteorological and nutrient conditions seems especially important.

3

New species of megaspores from the Trias of Poland

84%

Fuglewicz R.

Acta Palaeontologica Polonica

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1977

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tom 22

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nr 4

EN

Thirty new species and two new genera (Otynisporites, Bothriotriletes) of megaspores from the Trias of Polish Lowlands have been described. Most of them are from the Lower Keuper (Lettenkohle) and the Upper Buntsandstein. The megaspores from the Lower Buntsandstein have been described.

PL

Opisano 30 gatunków megaspor należących do 16 rodzajów, w tym wszystkie gatunki i 2 rodzaje nowe. Większość opisanych gatunków pochodzi z retu oraz kajpru dolnego (Lettenkohle). Po raz pierwszy opisano megaspory z pstrego piaskowca dolnego. Materiału do badań dostarczyły wiercenia z obszaru Niżu Polskiego wykonane przez Instytut Geologiczny i Przedsiębiorstwa Przemysłu Naftowego oraz jedno odsłonięcie w Lipiu Śląskim koło Lublińca. Próby do badań pobierano ze skał ilastych i mułowcowych o zabarwieniu szarym i zielonkawym. Do ich rozpuszczenia zastosowano HCl i HF. Otrzymane reziduum poddano flotacji przy użyciu cieczy ciężkiej. Megaspory badano w świetle odbitym, przechodzącym jak również za pomocą mikroskopu elektronowego.

RU

В настоящей работе представлены результаты палеонтологического изучения новых видов мегаспор из триасовых отложений Польши. Большинство описанных видов выделено из отложений рёта и нижнего кейпера. Впервые в настоящей работе описанны мегаспоры из отложений нижнего пёстрого песчаника. Исследования проводились на материалах буровых скважин пройденных на территории Польской низменности, а также одного обнажения в окрестности Люблинца. Опробование производилось в глинистых и алевролитовых осадках серой и зелёноватой окраски. Образцы обрабатывались соляной и плавиковой кислотами. Оставшиеся после обработки осадки подверглись сепарации в тяжёлой жидкости. Мегаспоры исследовались в отражённом и проходящем свете, а также в сканирующем электронном микроскопе. Описание охватывает 30 видов мегаспор принадлежащих к 16 родам, в том числе 2 рода и все виды новые.

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In vitro embryo sac development via ovule cultures in Doritis pulcherrima

84%

Ye X.-L. , Wu C.-H. , Liang C.-Y.

Acta Biologica Cracoviensia. Series Botanica. Supplement

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2005

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tom 47

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nr 1

5

Development of generative organs in pepino [Solanum muricatum Ait]

84%

Kopcinska J. , Lotocka B. , Kowalczyk K. , Kobryn J.

Acta Biologica Cracoviensia. Series Botanica. Supplement

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1999

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tom 41

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nr 1

6

Ovule, megaspores, and female gametophyte formation in Larix decidua Mill.

84%

Slobodnik B.

Acta Biologica Cracoviensia. Series Botanica. Supplement

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1999

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tom 41

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nr 1

7

Structural and biochemical changes in the micropylar region of Chondrilla juncea apomictic ovule

67%

Koscinska-Pajak M. , Chudzik B. , Zarzyka B. , Pawelec J.

Acta Biologica Cracoviensia. Series Botanica. Supplement

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2005

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tom 47

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nr 1

8

Salvinialean megaspores in the Late Cretaceous of southern Patagonia, Argentina

67%

Santamarina P. E. , Barreda V. D. , Iglesias A. , Varela A. N.

Acta Palaeontologica Polonica

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2018

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tom 63

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nr 3

EN

We report here two megaspores species related to the aquatic ferns of the order Salviniales from the Late Cretaceous Mata Amarilla Formation (Austral Basin), southern Santa Cruz Province, Argentina. We identified the species Arcellites disciformis and Balmeisporites cf. B. holodictyus. The presence of A. disciformis, in particular, is significant not only because it represents the first record for the Southern Hemisphere, indicating a bi-hemispheric distribution for the species, but also because it increases the diversity of this genus in Patagonia. The new findings of salvinialean megaspores highlight the importance of water ferns in the Late Cretaceous aquiferous enviroments of southern South America. The common occurrences of Arcellites and Balmeisporites, whether in shallow, fresh or brackish water facies, indicates aquatic paleoenvironment of the Mata Amarilla Formation, as was inferred also from the sedimentological evidence. Their presence also indicates that the lower and middle levels of the Mata Amarilla Formation can be attributed to the megaspore Zone M3 (Albian–Cenomanian) defined for the Cretaceous of Patagonia.