This contribution presents the record of an abundant assemblage of well-preserved, thallophytic noncalcified algae and of an epibiotic form that has been recognised as a putative graptolite from the upper Silurian (Ludlow, Gorstian–Ludfordian) of Podolia (western part of Ukraine). The sediments represent a shallow peritidal zone of the shelf. A new genus and species, Voronocladus dryganti, belonging to the Dasycladales Pascher, 1931, is established. Most of the specimens representing the algal thallus are overgrown by problematical epibiotic graptolites, described as Podoliagraptus algaeoides gen. et sp. nov. This phenomenon is explained as an epiphytic mode of life of the putative graptolite on algae, and is herein compared to recently known coexistences of algae with other organisms. The excellent state of preservation, and the abundance of studied Dasycladales algae and epibiotic problematics indicate that the investigated mudstone layer can be treated as a ‘Konservat Lagerstätte’ sensu Seilacher (1970).
Middle Triassic dasycladalean algae occur in limestones and dolstones of the Diplopora Beds in Upper Silesia, a region representing the southern part of the Germanic Basin. The dasycladales assemblage of this area was studied by Kotański at the end of the last century, mostly from dolomitized and weathered material. The relatively well-preserved specimens the authors found in thin sections from undolomitized strata allowed the description and revised taxonomical assignment of the algae. The identified microflora includes: Diplopora annulatissima Pia, 1920, Diplopora annulata (Schafhäutl, 1853), Salpingoporella cf. krupkaensis Kotański, 2013, Physoporella prisca Pia, 1912, Physoporella cf. pauciforata (Gümbel, 1872), Holosporella? sp. 1, and Holosporella? sp. 2. Diplopora annulatissima and Favoporella annulata Sokač, 1986 are regarded here as two different species. Oligoporella elegans Assmann ex Pia, 1931, extensively illustrated and described by Kotański (2013), is considered a junior synonym of Oligoporella prisca Pia, 1912, and transferred to the genus Physoporella emended by Grgasovic, 1995. Also, some of the dasycladalean algae (Salpingoporella cf. krupkaensis, Holosporella? sp. 1, and Holosporella? sp. 2) described here could represent new species, but more well-preserved material is necessary. The algae are accompanied by foraminiferal microfauna, which collectively indicate a late Anisian (Illyrian) age of the strata studied.
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