LIFE HISTORY OF COLPOMENIA SINUOSA (SYCTOSIPHONACEAE, PHAEOPHYCEAE) IN THE AZORES¹

Abstract

Colpomenia sinuosa (Mertens ex Roth) Derbès and Solier (Scytosiphonaceae, Phaeophyceae) is a common species on the rocky intertidal shores of the Azores, where reproductive gametophytes occur throughout the year. Life-history studies of this species were carried out in culture, and both sexual and asexual reproduction were observed. Anisogamous gametes fused to form zygotes. The zygotes gave rise to a filamentous prostrate sporophyte generation bearing unilocular sporangia, under both short-day and long-day conditions at 15 and 221 C, and to both unilocular and plurilocular sporangia, under the lower temperature condition. Unispores developed into gametophytes, and plurispores gave rise to filamentous sporophytes. Asexual reproduction was carried out by unfused female gametes and asexual plurispores produced from the same gametophyte. Unfused gametes developed into filamentous prostrate sporophytes producing unilocular sporangia in both culture conditions, and unispores released from the sporangia gave rise to gametophytes. Asexual plurispores from field gametophytes, under both culture conditions, developed directly into new gametophytes. The species exhibited three types of life history: a heteromorphic, diplohaplontic; a heteromorphic, monophasic (both with alternation between the erect and filamentous prostrate thalli); and a monomorphic, monophasic.

Phylogeography of Colpomenia sinuosa (Ectocarpales, Phaeophyceae) along the Brazilian coast

“…Colpomenia sinuosa life history is heteromorphic haplodiplobiontic, with erect yellowish to pale brown, convoluted, bladder‐like macroscopic gametophytic thalli alternating with a nearly microscopic filamentous tufty sporophytic thalli (Freitas Toste et al. 2003). Colpomenia sinuosa gametophytes can grow isolated or in clumps, epiphytic or epilithic, and present plurilocular reproductive structures organized in punctate sori (Freitas Toste et al.…”

“…Colpomenia sinuosa gametophytes can grow isolated or in clumps, epiphytic or epilithic, and present plurilocular reproductive structures organized in punctate sori (Freitas Toste et al. 2003, Cormaci et al. 2012, Lee et al.…”

“…The marine brown macroalga Colpomenia sinuosa is a common and conspicuous member of tropical and temperate intertidal reef habitats, worldwide (Lipkin 2002, Guiry andGuiry 2021). Colpomenia sinuosa life history is heteromorphic haplodiplobiontic, with erect yellowish to pale brown, convoluted, bladder-like macroscopic gametophytic thalli alternating with a nearly microscopic filamentous tufty sporophytic thalli (Freitas Toste et al 2003). Colpomenia sinuosa gametophytes can grow isolated or in clumps, epiphytic or epilithic, and present plurilocular reproductive structures organized in punctate sori (Freitas Toste et al 2003, Cormaci et al 2012, Lee et al 2013.…”

“…Colpomenia sinuosa life history is heteromorphic haplodiplobiontic, with erect yellowish to pale brown, convoluted, bladder-like macroscopic gametophytic thalli alternating with a nearly microscopic filamentous tufty sporophytic thalli (Freitas Toste et al 2003). Colpomenia sinuosa gametophytes can grow isolated or in clumps, epiphytic or epilithic, and present plurilocular reproductive structures organized in punctate sori (Freitas Toste et al 2003, Cormaci et al 2012, Lee et al 2013. The gametophyte bladder-like habit can trap air within its hollow thalli during low tide or when exposed to highenergy waves, increasing positive buoyancy, conferring floatability, allowing detached thalli to drift and hence disperse long distances (Blackler 1967, Mathieson et al 2016.…”

The genus Ellisolandia (Corallinaceae, Corallinales, Rhodophyta) in the Azores (NE Atlantic): character expression and taxonomic evaluation

“…C. elongata was previously reported to the archipelago by several authors (Castro & Viegas 1983, South & Tittley 1986, Prud'homme van Reine et al 1994, Tittley & Neto 1994, Neto 2000a, 2000b, Tittley & Neto 2000, Toste et al 2003, Wallenstein & Neto 2006). However, it was not possible to review their studied specimens, a reason why we cannot consider them as synonyms of Ellisolandia elongata.…”