Phylogeny of the lamprey genusLampetrainferred from mitochondrial cytochromeband ND3 gene sequences

Abstract

Mitochrondrial DNA analysis resolved many previously unanswered questions concerning the phylogeny of the lamprey genus Lampetra (comprising the subgenera Entosphenus, Lethenteron, and Lampetra). A total of 735 base pairs were sequenced from the cytochrome b and NADH dehydrogenase subunit 3 (ND3) genes in 11 lamprey species. With the exception of L . (E.) hubbsi from California, species of the Entosphenus subgenus formed a tight-knit clade that was very distinct from the other two subgenera. Lampetra hubbsi clustered with species of the Lampetra subgenus from the west coast of North America (L . ayresii and L . richardsoni) whereas species of the Lampetra subgenus from Atlantic drainages, namely the North American L . aepyptera and European L . fluviatilis, formed a third cluster. A fourth cluster included two species from the Lethenteron subgenus (L . japonica and L . appendix). Inclusion of published data from a third Lethenteron species, L . zanandreai, showed it to group with the L . (L .) fluviatilis lineage rather than with the other two Lethenteron species. Within each subgenus, members of paired and satellite species were closely related to one another (e.g., L . japonica and L . appendix) or were genetically indistinguishable (e.g., L . ayresii and L . richardsoni). Using rates of molecular evolution estimated in other fish taxa, these genetically indistinguishable species diverged less than 70 000 years ago.Résumé : L'analyse de l'ADN mitochrondial a permis de répondre à bon nombre de questions relativement à la phylogénie du genre de lamproie Lampetra (englobant les sous-genres Entosphenus, Lethenteron et Lampetra). On a déterminé la séquence d'un total de 735 paires de bases des gènes pour la cytochrome b et la sous-unité 3 de la NADH déshydrogénase (ND3) chez 11 espèces de lamproie. À l'exception de L . (E. ) hubbsi de la Californie, les espèces du sous-genre Enthosphenus formaient un clade cohérent très distinct de ceux des deux autres sous-genres. Lampetra hubbsi se rapprochait des espèces du sous-genre Lampetra de la côte ouest de l'Amérique du Nord

Phylogeny of Living Parasitic Lampreys (Petromyzontiformes) Based on Morphological Data

“…In selecting pairs of cyclostome species for Ks estimation, we treated the lamprey genus Lampetra as having the same distance the genus Lethenteron has from Petromyzon. This is based on a previous phylogenetic study using the cytochrome b and NADH dehydrogenase subunit 3 (ND3) genes (Docker et al, 1999), which is consistent with the classification by Potter (1980), who formerly considered that the three subgenera, Entosphenus, Lethenteron, and Lampetra, compose the single genus Lampetra. Despite the small number of genes sampled, similar Ks values were consistently obtained for Petromyzon-Lampetra and PetromyzonLethenteron pairs (Table 2).…”

“…The assembled sequences are available upon request. In analyses using the GCcontent of the third positions (GC3), we obtained similar results for all the graphs in this We treated the genus Lampetra as equally distant from Lethenteron in relation to Petromyzon based on the previous molecular phylogenetic study (Docker et al, 1999). Goldman and Yang (1994); PBL, Calculated with the method by Pamilo and Bianchi (1993) and Li (1993).…”

“…The hagfish genera Eptatretus and Paramyxine are not monophyletic to each other according to the molecular phylogenetic tree of the 16S rRNA gene (Kuo et al, 2003;Chen et al, 2005). The lamprey genera Entosphenus, Lampetra, and Lethenteron are not monophyletic to one another according to the molecular phylogenetic tree of the cytochrome b and NADH dehydrogenase 3 genes (Docker et al, 1999;see DISCUSSION for details). unambiguous with no gaps, with among-site rate heterogeneity taken into account (Yang, 1994).…”

Capture and collection of lampreys: the state of the science

“…Non-parasitic and parasitic species pairs (Potter 1980b) or satellite species (Vladykov and Kott 1980) co-occur in many river systems. Often, members of paired and satellite species are not even genetically distinguishable (Docker et al 1999). Due to unreliable species identification techniques, researchers have resorted to holding specimens until metamorphosis (Heard 1966;Beamish 1980), conducting post-hoc genetic or morphological identification (Filcek et al 2005;Meeuwig and Bayer 2005), or sampling only above impassable obstacles, where anadromous parasitic forms do not occur (Maitland 2003).…”

Comparative Studies of Bile Acid Release in the Mature Male Lampreys

“…The genus Lampetra is further divided into three sub-genera, Entosphenus, Lethenteron, and Lampetra, with Lampetra being the most derived of the subgenera. A recent study used two mitochondrial genes to examine the phylogeny of Lampetra, and found evidence for Entosphenus to be a separate taxon, but that the division between Lethenteron and Lampetra does not exist and that this combined group is derived from Entosphenus (Docker et al, 1999). Although it has not been established whether all the lamprey species can produce PZS during their larval stage, it is likely that PZS is common among larval lampreys, based on a recent study that revealed that larvae of Pacific and western brook lampreys can …”