Lumbriculids, branchiobdellidans and leeches: an overview of recent progress in phylogenetic research on clitellates
Brinkhurst, R.O. (1999). Lumbriculids, branchiobdellidans and leeches: an overview of recent progress in phylogenetic research on clitellates, in: Healy, B.M. et al. Aquatic Oligochaetes: Proceedings of the 7th International Symposium on Aquatic Oligochaetes held in Presque Isle, Maine, USA, 18-22 August 1997. Developments in Hydrobiology, 139: pp. 281-290. https://dx.doi.org/10.1007/978-94-011-4207-6_28 In: Healy, B.M.; Reynoldson, T.B.; Coates, K.A. (Ed.) (1999). Aquatic Oligochaetes: Proceedings of the 7th International Symposium on Aquatic Oligochaetes held in Presque Isle, Maine, USA, 18-22 August 1997. Reprinted from Hydrobiologia, vol. 406. Developments in Hydrobiology, 139. Springer Science+Business Media: Dordrecht. ISBN 978-94-010-5829-2; e-ISBN 978-94-011-4207-6. XIV, 290 pp. https://dx.doi.org/10.1007/978-94-011-4207-6, more In: Dumont, H.J. (Ed.) Developments in Hydrobiology. Kluwer Academic/Springer: The Hague; London; Boston; Dordrecht. ISSN 0167-8418, more |
| Abstract | The debates about the relationship among clitellate taxa at research conferences on aquatic oligochaetes have provided two alternative hypotheses. While both involve cladistic analyses, the differences focus on questions homology. A single unique synapomorphy supports a taxon consisting of Branchiobdellida plus Lumbriculidae. Muscle ultrastructure provides a potential autapomophy for Lumbriculidae within the clade, while Branchiobdellida has many autapomophies. Some proposed synapomorphies for a Branchiobdellida plus Hirudinea grouping (jaws, oral sucker) are not based on homologous structures. Others (loss of chaetae, median male pore) are not unique, or are based on potentially convergent characters. Initial molecular analyses support a Branchiobdellida - Hirudinea grouping. A preliminary manually drawn cladogram based on re-evaluated characters supports Lumbriculidae, Branchiobdellida, Acanthobdella and Euhirudinea as a monophyletic taxon. Observations on sperm ultrastructure support this hypothesis. If substantiated, a very considerable change in nomenclature will result. However, before any nomenclatural changes are proposed, a resolution of the apparently paraphyletic Oligochaeta is necessary. |
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