Macrodasyida (phylum Gastrotricha) comprises 365 species distributed across 34 genera and 10 families. However, current classification is under revision due to the contradictory results of molecular and morphological cladistic analyses. Studies aimed at bridging the gaps took advantage of supplementary assessments of poorly known species and particularly from observations of new taxa showing original traits that could help to identify plesiomorphic character states in these anatomically diverse micrometazoa.
View Article and Find Full Text PDFThis study gives additional, detailed information on the freshwater gastrotrich species described and reported from the southwestern regions of Ontario and New Brunswick, Canada by Schwank (1990). Aspidiophorus ontarioniensis, Chaetonotus (Chaetonotus) furculatus, Chaetonotus (Chaetonotus) ontariensis, Chaetonotus (Primochaetus) annae, Ichthydium malleum, Lepidodermella forficulata and Setopus lemnicola are all redescribed. In addition, a complete list of freshwater species currently known from North America is given.
View Article and Find Full Text PDFChaetonotus is the most speciose genus of the family Chaetonotidae within Gastrotricha, a small phylum of aquatic acoelomate invertebrates. The freshwater gastrotrich fauna of Sweden has been studied during the last five years and so far 44 species have been reported in the literature from the country. This study describes the new species, Chaetonotus (Primochaetus) veronicae n.
View Article and Find Full Text PDFAcoels are with few exceptions marine worms and a common component of the interstitial meiofauna. In this study we present new species to science belonging to Isodiametridae and Solenofilomorphidae. The new species, Isodiametra finkei n.
View Article and Find Full Text PDFBackground: Within an evolutionary framework of Gastrotricha Marinellina flagellata and Redudasys fornerise bear special interest, as they are the only Macrodasyida that inhabit freshwater ecosystems. Notwithstanding, these rare animals are poorly known; found only once (Austria and Brazil), they are currently systematised as incertae sedis. Here we report on the rediscovery of Redudasys fornerise, provide an account on morphological novelties and present a hypothesis on its phylogenetic relationship based on molecular data.
View Article and Find Full Text PDFBackground: Phylogenetic relationships within Gastrotricha are poorly known. Attempts to shed light on this subject using morphological traits have led to hypotheses lacking satisfactory statistical support; it seemed therefore that a different approach was needed.
Methodology/principal Findings: In this paper we attempt to elucidate the relationships within the taxonomically vast family Thaumastodermatidae (Macrodasyida) using molecular sequence data.