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Most upper Homerian and Ludfordian retiolitines have a tubarium with hexagonal meshes and a zigzag pattern in the middle part of their lateral walls, a shallow ancora umbrella, and a free nema. Hoffmanigraptus varsoviensis n. gen., n. sp. is described from isolated, three-dimensional material, from the upper part of the Colonograptus praedeubeli Biozone (upper Homerian, Silurian) of Poland, Baltica, and represents one of the earliest forms with this construction. This type of tubarium is represented by the upper Homerian Doliograptus Lenz & Kozłowska-Dawidziuk, 2002 and Spinograptus Bouček & Münch, 1952, differing from Hoffmanigraptus n. gen. mainly in larger proximal lateral orifices, pattern of clathrial lists on lateral walls, as well as size and shape of tubaria. Hoffmanigraptus n. gen. has a tubarium widening medially, tapering towards the distal end and forming a finite tubarium, with a possible three-vaned nematularium. Flattened specimens Plectograptus? ovatus Kozłowska, Lenz & Štorch, 2001 and Plectograptus? karlsteinensis Kozłowska, Lenz & Štorch, 2001, preserved on a rock surface from the Barrandian area are assigned to the new genus. They are of the same upper Homerian age, and show the main features of the new form. Hoffmanigraptus n. gen. is regarded as an early member of the Plectograptus clade. [ABSTRACT FROM AUTHOR]

Papiliograptus retimarginatus n. sp. is reported from the praedeubeli/deubeli Biozone, upper Homerian (Silurian) of the Bartoszyce IG-1 drill core of Poland, Baltica. It is the second species of the genus Papiliograptus Lenz & Kozłowska-Dawidziuk, 2002, belonging to the new retiolitid fauna of the recovery period after the lundgreni Extinction Event. Two characteristic features of the new retiolitid fauna are the development of a geniculum and singular or paired genicular structures. The new form has extremely wide, singular, reticulated genicular processes. It is suggested that these structures may have been an adaptation to prevent the planktonic colony from sinking in the water column. [ABSTRACT FROM AUTHOR]

The new retiolitid species, Spinograptus tubothecalis, is described from the Colonograptus praedeubeli and C. deubeli biozones from two localities in Poland: a borehole on the East European Platform and the Holy Cross Mountains. This was a recovery phase after the severe Silurian Cyrtograptus lundgreni Event. The new species has a unique, previously undescribed form of finite rhabdosome. Unlike the species Spinograptus reticulolawsoni and S. lawsoni, in which the finite rhabdosomes taper distally, its rhabdosome is parallel-sided with the two distal thecae developed as isolated tubes without genicular processes, with a small appendix between them. The new species also has preserved membranes of the sicula, thecae and ancora sleeve, similar to a few species of Spinograptus from the lower Homerian. Spinograptus tubothecalis, like Spinograptus clathrospinosus and S. spinosus, has paired reticulofusellar genicular processes on the prethecal ventral orifices, similar to but shorter than thecal processes. Transverse rods, a rare character in post-Cyrtograptus lundgreni Event retiolitids occur in the new species in rudimentary form. [ABSTRACT FROM AUTHOR]