Sargassum ilicifolium (Turner) C.Agardh

Fucus ilicifolius Turner, Fuci sive plantarum fucorum generi a botani - cis ascriptarum icones descriptiones et historia: 113 (Turner 1807).

Sargassum aquifolium sensu Coppejans et al. (2017), non Sargassum aquifolium (Turner) C.Agardh.

Sargassum crassifolium sensu Ang & Trono (1987); Trono (1992, 1997); Noiraksar & Ajisaka (2008); Coppejans et al. (2010); Santiañez & Trono (2013), non Sargassum crassifolium J.Agardh.

Sargassum cristaefolium sensu Ang & Trono (1987); Trono (1992, 1997); Modelo & Umezaki (1995), non Sargassum cristaefolium C.Agardh.

Sargassum turbinarioides sensu Trono (1997), non Sargassum turbinarioides Grunow.

TYPE LOCALITY. — Indonesia. Sunda Strait (Silva et al. 1996: 676).

SPECIMENS EXAMINED. — Philippines. Pangasinan, Bolinao, Malilnep, 9.III.2019, leg. A.C. Calaguing (MSI [MSI29137]); Ilocos Sur, San Esteban, Apatot, 26.IX.2018, leg. W.J.E. Santiañez (MSI [MSI29151, MSI29152, MSI29156, MSI29160]); Ilocos Sur, Santiago, Ambucao, 26.IX.2018, leg. W.J.E. Santiañez (MSI [MSI29174, MSI29176, MSI29186, MSI29187, MSI29189]); La Union, Balaoan, Almeida, 27.IX.2018, leg. W.J.E. Santiañez (MSI [MSI29196]); La Union, Balaoan, Paraoir, 27.IX.2018, leg. W.J.E.Santiañez (MSI [MSI29199, MSI29200, MSI29201]); La Union, San Fernando, Lingsat-MPA, 27.IX.2018, leg. W.J.E. Santiañez (MSI [MSI29206]).

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

DESCRIPTION

Thallus golden to dark brown in color, to 45 cm long, holdfast conical to discoid (Fig. 4). Main axes terete to slightly compressed, to 3 mm in diameter, warty, usually covered with epiphytes; secondary axes also terete or slightly compressed, smooth, slightly thinner than main axes (Fig.4C). Blades vertically attached, to 4 cm long, somewhat leathery or crisp when dried (Fig.4D); blade shape highly variable but mostly lanceolate to oblanceolate in vegetative branches (Fig. 4C, D, G), those in reproductive branches oblanceolate to obovate; apex often attenuate or acute, sometimes round or obtuse (Fig. 4 E-G); base usually asymmetrically cuneate; margin serrate to biserrate, sometimes erose or repand; some blades in terminal portion of the axes with duplicated apices perpendicular to the surface, some appearing turbinarioid (Fig. 4 C’; Fig. 4G: arrowhead); midrib thin, apparent from to 2/3 of the blade length, sometimes percurrent; cryptostomata embedded and randomly scattered on the surface of the blade; petiole short to 3 mm long, flattened or cylindrical, with occasional spine-like protrusions. Vesicles smooth, globose, to 5.4 mm in diameter, sometimes ribbed to mucronated or phyllocystic with few cryptostomata; stalks short, to 3 mm long (Fig. 4D, F). Dioecious, receptacles closely associated with blades and vesicles, arranged racemosely (Fig. 4E, F); female receptacles compressed to flattened with dentate margin (Fig. 4E), male receptacles cylindrical and lumpy (Fig. 4F).