New data on the taxonomy and localities of Ordovician trilobites (Trilobita: Ptychopariida:Illaenidae, Panderidae) of Leningrad Region

In this article twelve localities of trilobites of Keila Regional Stage (Katian Stage, Ordovician) are described: Elisavetilino quarry, Avkolevo quarry, Bornitzy quarry, Moloskovitzy quarry, Letoshitzy quarry, Luiskovitzy quarry, the north of Kalozhytzy quarry, the quarry in the Chrevitsa river in Kalozhytzy village, the Sumka river near Bolshoi Sumsk and Volpi villages, the Dolgaya river near the Skovorodenka estuary and Zagorie village. In the result of taxonomic and phylogenetic study one new genus Neoillaenus gen. nov., three new species: Panderia balashovae sp. nov., P. koshkarovi sp. nov., Stenopareia kossovae sp. nov. and one subspecies Dysplanus acutigenia putilovoensis subgen. nov. of the Latorp—Oandu (Frorian—Katian) Stages of the Leningrad region were discovered. Genus Neoillaenus gen. nov. included is presented by seven species: NeoiIllaenus atavus Eichwald, 1857; N. oblongatus (Angelin, 1854); N. excellens (Holm, 1886); N. kukersianus (Holm, 1886); N. itferensis (Holm, 1886); N. praecurriens (Jaanusson, 1957) и N. sp. 1. with a long flat shield, cephalon which is shorter in comparison with pygidium, big eye lobes, thorax with ten segments, thirteen—fourteen 30—40 terrace lines, short rachis of pygidium and dublure of pygidium with groove. Diagnosis and the lectotype of Stenopareia ava (Holm, 1886) were specified. In the Sumka river near Volpi village new bioherm with biofacies which included corals Lyopora sp. and trilobites Stenopareia ava (Holm, 1886) were found.