Molecular analysis resolves the taxonomy of the Laurencia complex (Rhodomelaceae, Ceramiales) in Bermuda and uncovers novel species of Chondrophycus and Laurenciella Author Popolizio, Thea R. Department of Biology, Salem State University, Salem, Massachusetts, 01970 (United States) tpopolizio @ salemstate. edu (corresponding author) Author Schneider, Craig W. Author Jongbloed, Walter M. Department of Biology, Trinity College, Hartford, Connecticut, 06106 (United States) Author Saunders, Gary W. Centre for Environmental & Molecular Algal Research, Department of Biology, University of New Brunswick, Fredericton, NB E 3 B 5 A 3 (Canada) Author Lane, Christopher E. Department of Biological Sciences, University of Rhode Island, Kingston, Rhode Island, 02881 (United States) text Cryptogamie, Algologie 2022 2022-01-26 20 1 1 30 http://dx.doi.org/10.5252/cryptogamie-algologie2022v43a1 journal article 10.5252/cryptogamie-algologie2022v43a1 1776-0984 Laurenciella namii Popolizio, C.W.Schneider & C.E.Lane , sp. nov. ( Fig. 4 ) HOLOTYPE . — CraigW. Schneider (CWS)/ Christopher E. Lane (CEL)/ Thea R. Popolizio (TRP) 12-11-2 [BDA0597] ( Fig. 4B ), 18.I.2012 , Spanish Point Park , north shore Bermuda I., Bermuda , western Atlantic Ocean , 32°18’26.4”N , 64°48’56.6”W , depth 0-2 m [deposited in MICH ]; isotypes – Bermuda Natural History Museum (BAMZ), Herb. CWS [BDA0598] ( Fig. 4A ), NY , UNB . HOLOTYPE DNA BARCODE . — GenBank OK209887, COI- 5P. PARATYPES . — Bermuda . CWS/CEL/TRP 10-16-12 [BDA0227], 21.VIII.2010 , Whalebone Bay , St. George’s I., 32°21’51.0”N , 64°42’43.5”W , depth 1 m ; CWS/CEL/TRP 10-33-13 [BDA0502] (see Appendix 1 ); CWS/CEL/TRP 10-33-15 [BDA0504], 25.VIII.2010 , Spanish Point Park , loc. cit ., depth 2 m ; CWS/CEL/TRP 12-8-1 [BDA0544], 17.VI.2012 , Brackish Pond Flats , north shore Bermuda I., 32°21’07.0”N , 64°48’02.5”W , depth 3-4 m ; TRP/CWS 12-143-4 [BDA1591], 25.X.2012 , Trunk I., Harrington Sound , 32°19’58.7”N , 64°43’33.9”W , depth 1-2 m ; CWS/TRP 13-20-4 [BDA1871], 18.IX.2013 , Whalebone Bay , loc. cit ., depth 1 m . Florida . CWS/ CEL/TRP/ D.C. McDevit (DCM) 13-9-5 [KW109] (see Appendix 1 ); CWS/CEL/TRP/DCM 13-9-17 [KW125], 29.V.2013 , Key West , White St. Pier, 24°32’45.4”N , 81°47’00.0”W , depth 2 m ; CWS/ CEL/TRP/DCM 13-9-25 [KW133], White St. Pier, loc. cit ., depth 2 m ; CWS/CEL/TRP/DCM 13-14-7 [KW219], 31.V.2013 , Cudjoe , Summerland Bridge , 24°39’39.0”N , 81°26’10.9”W , depth 1- 3 m . EPONOMY . — An honorific name for Professor Ki Wan Nam of Pukyong National University, Korea , who has played a significant role in the taxonomic diversification of the Laurencia complex using both morphological and phylogenetic data. DISTRIBUTION . — Bermuda and Florida , United States . SEASONALITY . — Collected throughout the year in Bermuda . DESCRIPTION Plants to 15 cm tall with main axes yellow-orange and deep red branchlets ( Fig. 4A ), fleshy; main axes lax, slender, to 1 mm diam., suboppositely to alternately spiraled branching and arising from discoidal holdfasts. Mature axes in lower portions, elongated and lacking branchlets, appearing denuded ( Fig. 4A ); upper portions demonstrating profuse alternate to irregular branching ( Fig. 4C ); ultimate branchlets cylindrical to clavate, to 2 mm long and 140-350 µm in diam. Vegetative axes with 4 pericentral cells; secondary pit connections present in cortical cells; cortical cells in surface view 20-45 µm diam., irregularly rounded-polygonal to ovoid, becoming more elongated in lower portions of branches, outer cortical cells often appearing obpyriform at branch apices; corps en cerise present in living plants, one per outer cortical cell; outer cortical cells acutely projecting, the surface appearing crenate in longitudinal section ( Fig. 4D, F ). In transverse section, two layers of pigmented cortical cells with three inner layers of colorless irregularly globose medullary cells 30-115 µm diam., decreasing in size radially toward the cortex ( Fig. 4E ). In section, outer cortical cells rounded-rectangular to ovoid or campanulate, 25-40 µm diam. and 20-35 µm long. Deep apical pits at branch apices bearing dense trichoblast systems to 220 µm long with 3-4 orders of subdichotomous branching ( Fig. 4F, G ). Reproductive structures not found. Distinct from other species of Laurenciella by its COI-5P and rbc L molecular sequences.