Sargassum polycystum C.Agardh

Santiañez, Wilfred John E., Lastimoso, John Michael L., Hoshino, Masakazu, Villafuerte, Brix Nester Q., Kogame, Kazuhiro & Gavino C. Trono, Jr, 2023, Molecular-assisted taxonomic study on the Sargassum C. Agardh (Fucales, Phaeophyceae) in northwestern Luzon, Philippines, Cryptogamie, Algologie 20 (7), pp. 127-142 : 134

publication ID	https://doi.org/ 10.5252/cryptogamie-algologie2023v44a7
DOI	https://doi.org/10.5281/zenodo.10020973
persistent identifier	https://treatment.plazi.org/id/F04E87AD-FFBB-1219-FEFE-FF7FFECA2294
treatment provided by	Plazi
scientific name	Sargassum polycystum C.Agardh
status

Treatment

Systema algarum: 304 ( Agardh 1824).

Sargassum myriocystum sensu Santiañez & Trono (2013) , non Sargassum myriocystum J.Agardh.

TYPE LOCALITY. — Indonesia. Sunda Strait ( Silva et al. 1996: 694).

SPECIMENS EXAMINED. — Philippines. Pangasinan, Bolinao, Dos Hermanos , 9.III.2019, leg. A.C. Calaguing ( MSI [ MSI29138 , MSI29139 ]); Pangasinan, Bolinao, Malilnep , 9.III.2019, leg. A.C. Calaguing ( MSI [ MSI29140 ]); Ilocos Norte, Burgos, Bayog , 25.IX.2018, leg. W.J.E. Santiañez ( MSI [ MSI29141 , MSI29142 , MSI29143 , MSI29144 , MSI29148 ]); La Union, Balaoan, Almeida , 27.IX.2018, leg. W.J.E. Santiañez ( MSI [ MSI29197 ]).

DISTRIBUTION IN NORTHWESTERN LUZON. — Ilocos Norte, Ilocos Sur, La Union, Pangasinan ( Fig. 1 View FIG ).

DESCRIPTION

Thallus golden (when fresh) to dark brown (when dried) in color, to 57 cm long, holdfast discoid. Main axis terete, warty, short, usually to 5 mm long (rarely to 18 mm long), bearing several secondary axes, some of which are modified into stoloniferous holdfast ( Fig. 5 View FIG A-C). Secondary axes with numerous short protuberances, these either densely aggregated or sparsely distributed throughout the surface ( Fig. 5A, D View FIG ); secondary axes of some specimens smooth ( Fig. 5E View FIG ). Blades on vegetative branches large, to 60 mm long, 13 mm wide, oblong to oblanceolate, base asymmetrical, margin serrate-dentate, apices acute to rounded, cryptostomata elevated and scattered, midrib distinct, disappearing before the tip; those in fertile branches considerably smaller, less than 15 mm long, 6 mm wide, obovate, some oblong to somewhat oblanceolate, base asymmetrical, margin serrate dentate, midrib usually not apparent, but only occur in the basal 1/3 of the blades when present, apices rounded to obtuse. Vesicles small, generally less than 2 mm long and 1.5 mm wide, numerous, spherical to ovoid, often with a short and thin or foliaceous mucro, subtended by short (sometimes as long as vesicles) and thin stalks ( Fig. 5D, E View FIG ). Plant dioecious ( Fig. 5F, G View FIG ), receptacles closely associated with vesicles and/or blades (zygocarpic), racemosely arranged; female receptacles toothed, compressed (rarely triquetrous) to flattened towards the tip, sometimes somewhat twisted, generally less than 2.5 mm long, 1 mm at the widest ( Fig. 5F View FIG ); male receptacles smooth, filiform, to 5 mm long, cylindrical in cross-section, to 0.5 mm in diameter ( Fig. 5G View FIG ).