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 THE GENUS LAURENCIA IN BERMUDA COI-5P and rbc L sequence data support the recognition of two species for collections long called Laurencia obtusa in Bermuda , both of which are distantly related to true L. obtusa from Europe. These species represent examples of western Atlantic entities with a misassigned European binomial placed upon them by phycologists of the 19th and early 20th centuries (see Popolizio et al. 2013 ). The rbc L barcode gap analysis presents support for the conspecificity of Bermuda specimens with Laurencia dendroidea and L. catarinensis from Brazil ( Cassano et al. 2012a ; Machín-Sánchez et al. 2012 ). Intraspecific divergences in rbc L for the two are 0.5% and 0.3%, respectively, compared with interspecific divergences of 5.5% and 3.7% ( Table 1 ). These species herein represent new reports for Bermuda . Our collections of these two species had previously been assigned to L. obtusa , but our molecular data suggest L. obtusa is not found in Bermuda and likewise may not be present in the tropical western Atlantic. These data also show that both species are present in the Florida Keys and St. Croix FIG . 4. — Laurenciella namii Popolizio, C.W.Schneider & C.E.Lane sp. nov. A , isotype specimen [ CWS/CEL/TRP 12-11-2/BDA0598]; B , holotype specimen [ CWS/ CEL/TRP 12-11-2/BDA0597]; C , axial tip displaying irregular branching [ CWS/CEL/TRP/DCM 13-9-17/KW125]; D , Longitudinal section of branch with outer cortical cells demonstrating a crenate margin [ CWS/CEL/TRP/DCM 13-9-17/KW125]; E , transverse section of axis showing two outer layers of corticated pigmented cells and four inner layers of colorless, irregularly globose medullary cell layers [ CWS/CEL/TRP/DCM 13-9-17/KW125]; F , longitudinal section of axial tip illustrating apical pit, trichoblasts and crenate outer margins [ CWS/CEL/TRP/DCM 13-9-5/KW109]; G , longitudinal section of axial tip; orientation shows depth of apical pit and developing trichoblasts [ CWS/CEL/TRP/DCM 13-9-17/KW125]. Scale bars: A, 2 cm; B, 1 cm; C, 500 µm; D, F, G, 50 µm; E, 100 µm. TABLE 3. — Morphological character comparisons for treatments of Laurencia microcladia Kützing , L. caduciramulosa Masuda & S.Kawaguchi , L. laurahuertana Mateo-Cid, Mendoza-Gonzalez, Sentíes & Díaz-Larrea and L. venusta Yamada.
Laurencia Laurencia Laurencia Laurencia Laurencia Laurencia
microcladia microcladia caduciramulosa caduciramulosa laurahuertana venusta Laurencia venusta
Location of West Indies Bermuda Vietnam Florida, United Caribbean Caribbean Mexico Korea and Japan
specimens (type locality) (type locality) States Mexico (type locality)
used for data (type locality)
Thallus color Gray-green to Green to deep Purple-red Greenish-brown Pale green Pale green Brown, greenish
purple-green purple-red, often or purple red or
with distinct brown with pink
purple-red branch tips
branchlet tips
Length of uprightto 10 to 6.5 2-5 to 1 to 0.7 to 7 to 10
axes (cm)
Branching Alternately to Alternately to Irregularly Irregularly Sparse, Sparse, Irregularly alternate,
pattern irregularly irregularly alternate and alternate dichotomous verticillate, 2-4 subopposite or
branched, branched, spirally arranged and spirally below, branches per subverticillate;
dense distally dense distally; arranged, irregularly verticile, less occasionally
some branches usually with alternate above commonly curved branches
clustered, 2-3 orders of opposite, with secund
appearing branches alternate or ultimate
whorled irregular branchlets
Outer cortex cell 30-60 15-50 10-30 distally, 23-45 Not reported 14-52 33-58
diam. (μm) on 20-36 proximally
main axes
Outer cortex Not reported Absent Slightly near Present Present Absent Absent or slight
cross- branch apices (undulate)
sectional cell
projection
Tetrasporangial Not reported Parallel Not reported Not reported Not reported Parallel Parallel
arrangement
Tetrasporangia Spherical Spherical to Not reported Not reported 60-65 µm diam. 40-80 µm diam. 75-86 µm diam.
to ovoid; slightly ovoid;
65-100 µm 60-100 µm diam.
diam.
Cystocarp Spherical to urn- Urn-shaped, Not reported Not reported Urn-shaped Prominent; Urn-shaped
shape shaped; near situated near laterally to conical or
branchlet tips branchlet tips positioned ovoid without
to bearing a protuberant
branchlet; urn- ostiole
shaped to
conical
Cystocarp diam.500-700 600-820 Not reported Not reported 450-500 400-600 600-870
(μm)
Carposporangia Not reported Obpyriform, Not reported Not reported Pyriform; 100-150 μm long, Not reported
80-125 μm long, 90-100 µm 30-50 μm diam.
30-60 μm diam. long, 22-25 μm
diam.
Spermatangia Not reported Spherical to ovoid; Not reported Not reported Ovoid, 11-13 µm Ovoid; 6-11 µm Ovoid; 10-12 µm,
4.5-10 μm diam.; long, 3-4 μm long, 4-7 μm 5-7 μm diam.;
sterile apical diam.; sterile diam.; sterile sterile apical cells
cells present apical cells apical cells present
absent present
References for Taylor 1960 ; Present study Masuda et al. Collado-Vides Mateo-Cid et al. Sentíes et al. 2001 Yamada 1931; Saito
data Howe 1918 ; 1997 et al. 2014 2014 1967; Nam et al.
Littler & Littler 2000
2000 ; Dawes &
Mathieson 2008
in the US Virgin Islands . Notably, specimens we have identified as having “red” habits in our collections group only within the L. dendroidea clade, along with green and purple-green morphs of this species. All specimens that were noted as ‘green with pink tips’ in our field notes fall within the L. catarinensis clade. It is likely that Howe (1918) was examining collections of L. catarinensis when describing ‘ L. obtusa ’ from the islands as “subglobose tufts’’ that are “often greenish with red tips,” features that appear to characterize the habit of this species based on our observations and genetic sequences. The presence of Laurencia intricata in Bermuda also has been verified with molecular data. Sequence data show that this species, first reported for the islands by Howe (1918) , is conspecific with specimens from the Caribbean Antilles, the type locality of this species. Intraspecific divergence values are 0.1% in COI-5P and 0.3% in rbc L ( Table 1 ). We have discovered a specimen of L. intricata among Hervey’s archived