New species and new records of freshwater Chaetonotida (Gastrotricha) from Sweden

Abstract

Gastrotricha is a small phylum of acoelomatic aquatic invertebrates common in both marine and freshwater environments. The freshwater gastrotrich fauna of Sweden is poorly known and so far only 20 species have been reported. In this study two species, Heterolepidoderma joermungandri n. sp. and H. trapezoidum n. sp., are described as new to science. Moreover, 9 species are presented as new to the Swedish fauna. Additional taxonomic information is also given for 4 species previously reported from the country. In total 7 genera of two families, Chaetonotidae and Dasydytidae, are presented and the number of reported freshwater gastrotrichs from the country is increased to 31.

Structure, function and evolution of somatic musculature in Dasydytidae (Paucitubulatina, Gastrotricha)

“…Nevertheless, we here assign our specimens to the species H. crassus. In a recent faunistic paper on Swedish freshwater Gastrotricha, even smaller specimens measuring between 97 and 130 lm were identified as H. crassus (Kånneby 2011). Numeric characters of some of our Dasydytes (Dasydytes) goniathrix specimens (i.e., number of spine groups and number of spines per group) differ from the data provided in the literature even though the spine number is known to be a variable character in that species (Schwank 1990).…”

Gastrotricha – not only in sediments: new epiphytic species of Chaetonotida from the Jubilee Greenhouse of the Botanical Garden in Kraków

“…Lepidodermella squamata is a widely distributed species or, more precisely, in the light of the current data, it represents sets of cryptic or morphologically similar species noted in Europe, inter alia reported from Bulgaria (Valkanov 1937), Germany (Remane 1935-36), Great Britain (Martin 1981), Italy (Mola 1932), Poland (Roszczak 1936;Kisielewska & Kisielewski 1986a, 1986b, 1986c, Romania (Rudescu 1967), Sweden (Kånneby 2011) and Switzerland (Greuter 1917); also reported from Argentina (Grosso & Drahg 1984), Australia (Hochberg 2005), Brazil (Kisielewski 1991), Canada (Schwank 1990), East Africa (Daday 1910), India (Naidu & Rao 2004), Israel (Kisielewski 1999), Japan (Sudzuki 1971), South Korea (Lee & Chang 2000), the United States (Bryce 1924) and Uruguay (Cordero 1918).…”

New Reports of Gastrotricha for the North-Eastern Ukraine

“…Material of Gastrotrichs was collected from September 2018 to February 2019 in Karyakiv ravine pond (49,6157 N 36,3148 E) (a territory of National park "Homilshanski lisy" and a part of V. N. Karazin National University Biological station Zmiiv District) in the Kharkiv Region, North-East of Ukraine. Gastrotrichs were sampled with using a plastic cylinder for benthic sampling at depth between 0.1 to 1 m. Vegetation was collected by hand (Kånneby, 2011). Samples were taken back to the laboratory of V. N. Karazin National University where they left thawing with ice for a few days.…”

“…Classification of Gastrotricha is mainly based on morphology and ultrastructure (Schwank, 1990). Morphometry of the body and in particular of some structures, such as the furca and the pharynx are important characters for species identification as well as distribution and shape of scales and spines (Kånneby, 2011).…”