Large subunit rDNA gene sequences and reproductive morphology revealStenopeltisto be a member of the Liagoraceae (Nemaliales, Rhodophyta), with a description ofAkalaphycusgen. nov.

Abstract

A morphological and gene sequence study has shown the red algal genus Stenopeltis to be a member of the Liagoraceae (Nemaliales), not the Polyidaceae (Gigartinales) where it was placed after being segregated from Rhodopeltis. Post-fertilization events in Stenopeltis gracilis (the type of the genus) include a spreading, diffuse gonimoblast arising directly from the zygote ( = post-fertilization carpogonium), and no auxiliary cells, features characteristic of the Liagoraceae. Moreover, phylogenetic analyses based on LSU (large subunit) rDNA sequences clearly place Stenopeltis in a clade with members of the Liagoraceae. These observations are at odds with the existing taxonomic placement of the genus and a re-interpretation of earlier observations purporting to show the presence of auxiliary cells is presented. The morphology and reproduction of the three species currently attributed to the genus, S. gracilis (the type), S. setchelliae, and S. liagoroides, are described. LSU sequences as well as carpogonial branch and cystocarp morphology of S. setchelliae are distinct from those of S. gracilis (the type), and the segregate genus Akalaphycus is proposed to accommodate S. setchelliae and S. liagoroides.

A phylogenetic re‐appraisal of the family Liagoraceae sensu lato (Nemaliales, Rhodophyta) based on sequence analyses of two plastid genes and postfertilization development

“…Chaetangiaceae was elevated to ordinal status by Desikachary (1964), but this has largely been ignored. Monophyly of the order has been demonstrated by Huisman et al (2004a,b) based on large-subunit ribosomal DNA sequences, and Huisman et al (2004a) also added a third family, the Scinaiaceae. However, relationships among genera in the family Liagoraceae sensu lato have remained mostly unexplored (Le Gall andSaunders 2010, Lin et al 2011a,b).…”

“…Monophyly of the order has been demonstrated by Huisman et al. (,b) based on large‐subunit ribosomal DNA sequences, and Huisman et al. () also added a third family, the Scinaiaceae.…”

“…(,b) based on large‐subunit ribosomal DNA sequences, and Huisman et al. () also added a third family, the Scinaiaceae. However, relationships among genera in the family Liagoraceae sensu lato have remained mostly unexplored (Le Gall and Saunders , Lin et al.…”

Resurrecting the red algal genusGraniawithin the order Acrochaetiales (Florideophyceae, Rhodophyta)

“…To the best of our knowledge A. efflorescens had not been subjected to molecular analysis. We therefore sequenced nuclear large subunit ribosomal DNA (LSU), a region demonstrated to be taxonomically informative in the red algae at the ordinal level and below (Freshwater et al, 1999;Harper & Saunders, 2002;Huisman et al, 2004;Saunders & Lehmkul, 2005), to assess its molecular relationship to other acrochaetioid algae. …”

Stream Macroalgae of the Hawaiian Islands: A Floristic Survey

“…The only study to date of Hawaiian stream macroalgae including molecular data is a phenologic and phylogenetic study of the endemic red alga Batrachospermum spermatiophorum ), which confirmed the endemic status of the species by comparison of rbcL gene sequence data with worldwide congeners. The Hawaiian representatives of the marine red algal order Nemaliales have recently undergone substantial revision based on combinations of anatomical and molecular data (e.g., Huisman et al 2003Huisman et al , 2004a, and many changes may also be forthcoming for the freshwater flora following similar kinds of studies. Specifically, several potentially undescribed taxa were collected during the survey reported here (e.g., two Phormidium taxa and two Cladophora taxa).…”