Morphological and molecular studies on Gelidiaceae and Gelidiellaceae (Gelidiales, Rhodophyta) from Brazil with description of the new species Gelidium calidum Author Jamas, Mayra Postgraduate Program “ Biodiversidade Vegetal e Meio Ambiente ”, Institute of Botany, São Paulo, São Paulo 04301 - 902, Brazil Author Iha, Cintia Departament of Botany, Institute of Biosciences, University of São Paulo, São Paulo, São Paulo 05508 - 090, Brazil Author Oliveira, Mariana C. Departament of Botany, Institute of Biosciences, University of São Paulo, São Paulo, São Paulo 05508 - 090, Brazil Author Guimarães, Silvia M. P. B. Institute of Botany, Research Center in Phycology, São Paulo, São Paulo 04301 - 902, Brazil Author Fujii, Mutue T. Institute of Botany, Research Center in Phycology, São Paulo, São Paulo 04301 - 902, Brazil text Phytotaxa 2017 2017-07-25 314 2 195 218 http://dx.doi.org/10.11646/phytotaxa.314.2.2 journal article 10.11646/phytotaxa.314.2.2 1179-3163 13686312 Millerella myrioclada (Børgesen) G.H.Boo Figs. 3 C–D ; 4 K–N Thalli erect, compressed, delicate and dark red, forming dense tufts, up to 1.5 cm ( Fig. 3 C ). Erect axes are sparingly and irregularly branched ( Fig. 3 D ). Apex acute with prominent apical cell having a pattern of malting division of subapical cells, resulting in an axial filament visible below the apex ( Fig. 4K ). Cross section of median region of the main thalli shows three layers of medullary cells formed by axial and periaxial cells produced in a distinctive transverse row of thick-walled cells that remain evident in most plant parts ( Fig. 4 L ). Rhizines absent. Fixing by independent rhizoidal filaments ( Fig. 4 M ). Tetrasporangia divided decussately cruciate, arranged in chevrons, thus V-formation without sterile margins ( Fig. 4 N ).