Zhytomyr State University LibraryKaryotypes of two European species of the genus Lymnaea with disputable taxonomic status (Gastropoda: Pulmonata: Lymnaeidae)А. V.GarbarauthorА. V.KornіushіnauthorKaryotypes of Lymnaea corvus and L. occulta are studied for the first time and compared to the original data on Ukrainian populations of L. palustris and L. stagnalis. While all the studied species have the same diploid chromosome number (2n = 36), they differ in chromosome morphology. Karyotypes of L. occulta and L. palustris include only biarmed chromosomes (number of arms = 72). In contrast, L. corvus and L. stagnalis have also uniarmed (acrocentric) chromosomes (number of arms = 60 and 62, respectively). Karyological data confirm specific distinctness of L. occulta and L. corvus; however, similarity in the chromosome morphology of the latter species to L. stagnalis is probably based on symplesiomorphies and, thus, cannot support phylogenetic relationship suggested earlier on the basis of anatomical characters. Kurzfassung. Karyotypen von zwei europдischen Arten der Gattung Lymnaea mit umstrittenem taxonomischen Status (Gastropoda: Pulmonata: Lymnaeidae). - Karyotypen von Lymnaea corvus und L. occulta wurden erstmalig untersucht und mit den originalen Daten fьr ukrainische Populationen von L. stagnalis und L. palustris verglichen. Alle untersuchten vier Arten weisen dieselbe Anzahl diploider Chromosomen auf (2n = 36), kцnnen aber durch die Morphologie der Chromosomen unterschieden werden. Die Karyotypen von L. occulta enthalten nur zweiarmige Chromosomen (Anzahl der Arme = 72). Im Gegensatz hierzu weisen L. corvus und L. stagnalis auch einarmige (akrozentrische) Chromosomen auf (Anzahl der Arme = 60 beziehungsweise 62). Die karyologischen Befunde bestдtigen die spezifische Verschiedenheit von L. occulta und L. corvus; jedoch ist die Дhnlichkeit in der Chromosomenmorphologie der letzteren Art gegenьber L. stagnalis wahrscheinlich auf Symplesiomorphien zurьckzufьhren, deshalb kann die frьher auf der Basis anatomischer Merkmale behauptete phylogenetische Verwandtschaft von L. corvus und L. stagnalis nicht unterstьtzt werden.QL Zoology2002Article

For work being deposited by its own author: In self-archiving this collection of files and associated bibliographic metadata, I grant Zhytomyr State University Library the right to store them and to make them permanently available publicly for free on-line. I declare that this material is my own intellectual property and I understand that Zhytomyr State University Library does not assume any responsibility if there is any breach of copyright in distributing these files or metadata. (All authors are urged to prominently assert their copyright on the title page of their work.)

For work being deposited by someone other than its author: I hereby declare that the collection of files and associated bibliographic metadata that I am archiving at Zhytomyr State University Library) is in the public domain. If this is not the case, I accept full responsibility for any breach of copyright that distributing these files or metadata may entail.

Clicking on the deposit button indicates your agreement to these terms.