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Abstract

The Family Kumpanophyllidae Fomichev, 1953, synonymised by Hill (1981) with the Family Aulophyllidae Dybowski, 1873, is emended and accepted as valid. The new concept of this family, based on both new collections and discussion on literature data, confirms the solitary growth form of its type genus Kumpanophyllum Fomichev, 1953. However, several fasciculate colonial taxa, so far assigned to various families, may belong to this family as well. The emended genus Kumpanophyllum forms a widely distributed taxon, present in Eastern and Western Europe and in Asia. Its Serpukhovian and Bashkirian occurrences in China vs Bashkirian occurrences in the Donets Basin and in Spain, may suggest its far-Asiatic origin, but none of the existing taxa can be suggested as ancestral for that genus. Thus, the suborder position of the Kumpanophyllidae remains unknown. Four new species: K. columellatum, K. decessum, K. levis, and K. praecox, three Kumpanophyllum species left in open nomenclature and one offsetting specimen, questionably assigned to the genus, are described.
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Abstract

A new Subfamily Dirimiinae of the Family Kumpanophyllidae Fomichev, 1953 is introduced on the basis of Dirimia gen. nov., which is represented by six new named species and three species left in open nomenclature. The new species are Dirimia multiplexa, D. similis, D. recessia, D. composita, D. extrema, D. nana, Dirimia sp. 1, Dirimia sp. 2 and Dirimia sp. 3. The progressing atrophy of the columnotheca, leading to its total reduction in extreme species, and the occurrence of an axial structure instead of a compact pseudocolumella established in these species are accepted as differences exceeding the genus level. All specimens assigned to this subfamily were derived from the same Limestone F1 of the Donets Basin, and mostly from the same locality. The reasons for their split into a relatively large number of species are: 1) an increased radiation typical for faunal turnover times; 2) a delay in the appearance of differentiated skeletal characters relative to the appearance of genetic differences large enough to characterise different species; 3) a bias in preservation of fossil remnants by comparison to living populations, amplified by biases in the collections available for study by comparison to the total number of specimens fossilised.
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