Gelidium lineare Iha & Freshwater

Jamas, Mayra, Iha, Cintia, Oliveira, Mariana C., Guimarães, Silvia M. P. B. & Fujii, Mutue T., 2017, Morphological and molecular studies on Gelidiaceae and Gelidiellaceae (Gelidiales, Rhodophyta) from Brazil with description of the new species Gelidium calidum, Phytotaxa 314 (2), pp. 195-218 : 205

Gelidium lineare Iha & Freshwater

Figs. 5 D ; 7 A–F

Thalli are attached, dark red-brown, up to 12.5 cm. Main axes had one to three orders of opposite, pinnate marginal branching ( Fig. 5 D ). Apex obtuse, with the apical cell between two lobes ( Fig. 7 A ). Brush-like haptera. Many rhizines concentrated between the outer medulla and inner cortex ( Fig. 7 B ). Tetrasporangia sori were generally surrounded by wide sterile margins ( Fig. 7 C ). Tetrasporangia divided decussately cruciate ( Fig. 7 D ). Male gametophytes found in main and lateral branches may have more than one sorus per branch ( Fig. 7 E ). Spermatia originated by transverse divisions of elongated outer cortical cells ( Fig. 7 F ).

Figures

FIGURE 5. Habit of the Gelidiaceae species. A–B. Gelidium crinale (A:SP469061, B:SP469067). Scale bar = 1 cm. C. Gelidium floridanum (SP469068). Scale bar = 2 cm. D. Gelidium lineare (SP469091). Scale bar = 1 cm. E. Gelidium microdonticum (SP469070). Scale bar = 0.5 cm.

FIGURE 7. A–F. Gelidium lineare. A. Detail of the apical portion showing the apical cell between two lobes (SP469087). Scale bar = 25 μm. B. Cross section of the middle region of the the main branch (SP469087). Scale bar = 100 μm. C. Detail of tetrasporangial branch (SP469091). Scale bar = 250 μm. D. Cross section of tetrasporangial branch, showing cruciately divided tetrasporangia (SP469091). Scale bar = 100 μm. E. Detail of male gametophyte branches, which may have more than one sorus per branch (SP469087). Scale bar = 500 μm. F. Cross section of male gametophyte branch, showing spermatia originated by transverse divisions (arrow) of elongated outer cortical cells (SP469087). Scale bar = 20 μm. G–K. Gelidium microdonticum (SP469070). G. Detail of the apical portion showing the apical cell between two lobes. Scale bar = 100 μm. H. Cross section of the middle region of the the main branch. Scale bar = 100 μm. I. Detail of the thallus, showing abundant rhizines in the medullary region. Scale bar = 250 μm. J. Tetrasporangial branch. Scale bar = 100 μm. K. Cross section of tetrasporangial branch, showing cruciately divided tetrasporangia. Scale bar = 100 μm.