Lobophora pachyventera Z.Sun, P.E.Lim, J.Tanaka & H.Kawai

Kwan, Valerie, Yip, Zhi Ting, Fong, Jenny & Huang, Danwei, 2021, Diversity and phylogeny of the brown alga Lobophora (Dictyotales, Phaeophyceae) in Singapore, Phytotaxa 496 (3), pp. 215-227 : 224

Lobophora pachyventera Z.Sun, P.E.Lim, J.Tanaka & H.Kawai in Sun et al. (2012: 507)

Specimens observed:— LOBO08, LOBO22, LOBO23, LOBO24, LOBO26, LOBO27, LOBO31, LOBO33, LOBO39, LOBO42, LOBO43 (Reef Ecology Laboratory, NUS)

Description:— Thallus large and flabellate with two distinct morphotypes. First morphotype (LOBO22, LOBO24, LOBO26, LOBO33, LOBO42) thallus exhibits decumbent growth form ( Fig. 4G ). Base of thallus narrow, growing with basal parts attached to substrate and distal parts curving upwards. Margin entire. Thallus 3 cm wide and 2.7 cm tall, dark brown. Thallus 141–214 μm thick, composed of a single layer of medulla cells, 2–3 layers of dorsal cortical cells, and 2–4 layers of ventral cortical cells ( Fig. 4H and 4I ). Medulla cells 34–148 μm wide and 43–93 μm thick. Dorsal and ventral cortical cell layers 37–81 μm and 38–81 μm thick respectively. Second morphotype (LOBO08, LOBO23, LOBO27, LOBO31, LOBO39, LOBO43) thallus exhibits crustose growth form ( Fig. 4G , inset). Base of thallus narrow, strongly attached to the substratum. Margin entire. Thallus 2 cm wide and 2 cm tall, orange to reddish brown. Thallus 179–305 μm thick, composed of a single layer of medulla cells, 2–3 layers of dorsal cortical cells, and 2–4 layers of ventral cortical cells. Medulla cells 92–204 μm wide and 71–133 μm thick. Dorsal and ventral cortical cell layers 51–87 μm and 179–305 μm thick respectively.

Holotype:— SAP109519 . Sunayama Beach , Miyakojima Island, Okinawa, Japan. 9 May 2009. Collected by J. Tanaka & Z. Sun.

Distribution:— China, Malaysia, Japan ( Sun et al. 2012), New Caledonia ( Vieira et al. 2014), Taiwan, Vanuatu, ( Vieira et al. 2016), Singapore (this study).

Habitat:—Reef flat (1–2 m depth) and reef crest (3–4 m depth). Commonly growing on hard substratum and coral rubble, sometimes epiphytically on coralline algae.

Figures

FIGURE 4. Morphological observations of Lobophora species found in Singapore. Lobophora challengeriae in situ (A), L. challengeriae longitudinal section (B), L. challengeriae transverse section (C). Lobophora lamourouxii in situ (D) (inset: sori), L. lamourouxii longitudinal section (E), L. lamourouxii transverse section (F). Lobophora pachyventera morphotype 1 in situ (G) (inset: morphotype 2), L. pachyventera longitudinal section (H), L. pachyventera transverse section (I). Lobophora sp61 in situ (J), Lobophora sp61 longitudinal section (K), Lobophora sp61 transverse section (L). The metallic scale is 2.5 cm in width (A, D, G, J). Scale bars represent 0.1 mm.