<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE article  PUBLIC "-//NLM//DTD Journal Publishing DTD v3.0 20080202//EN" "http://dtd.nlm.nih.gov/publishing/3.0/journalpublishing3.dtd"><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" dtd-version="3.0" xml:lang="en" article-type="research article"><front><journal-meta><journal-id journal-id-type="publisher-id">AJPS</journal-id><journal-title-group><journal-title>American Journal of Plant Sciences</journal-title></journal-title-group><issn pub-type="epub">2158-2742</issn><publisher><publisher-name>Scientific Research Publishing</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.4236/ajps.2020.112009</article-id><article-id pub-id-type="publisher-id">AJPS-98081</article-id><article-categories><subj-group subj-group-type="heading"><subject>Articles</subject></subj-group><subj-group subj-group-type="Discipline-v2"><subject>Biomedical&amp;Life Sciences</subject></subj-group></article-categories><title-group><article-title>
 
 
  &lt;i&gt;Gracilariopsis lemaneiformis&lt;/i&gt; (Gracilariaceae, Rhodophyta) in the Mexican Coasts: A Case of Disjunct Distribution?
 
</article-title></title-group><contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Oscar</surname><given-names>E. Hernandez</given-names></name><xref ref-type="aff" rid="aff1"><sup>1</sup></xref><xref ref-type="corresp" rid="cor1"><sup>*</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Kurt</surname><given-names>M. Dreckmann</given-names></name><xref ref-type="aff" rid="aff2"><sup>2</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>María</surname><given-names>Luisa Nuñez-Resendiz</given-names></name><xref ref-type="aff" rid="aff2"><sup>2</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Martha</surname><given-names>Isabel Vilchis</given-names></name><xref ref-type="aff" rid="aff2"><sup>2</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Abel</surname><given-names>Sentíes</given-names></name><xref ref-type="aff" rid="aff2"><sup>2</sup></xref></contrib></contrib-group><aff id="aff2"><addr-line>Departamento de Hidrobiología, Universidad Autónoma Metropolitana-Iztapalapa, Mexico City, México</addr-line></aff><aff id="aff1"><addr-line>Doctorado en Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana-Iztapalapa, Mexico City, México</addr-line></aff><pub-date pub-type="epub"><day>22</day><month>01</month><year>2020</year></pub-date><volume>11</volume><issue>02</issue><fpage>111</fpage><lpage>124</lpage><history><date date-type="received"><day>10,</day>	<month>December</month>	<year>2019</year></date><date date-type="rev-recd"><day>28,</day>	<month>January</month>	<year>2020</year>	</date><date date-type="accepted"><day>31,</day>	<month>January</month>	<year>2020</year></date></history><permissions><copyright-statement>&#169; Copyright  2014 by authors and Scientific Research Publishing Inc. </copyright-statement><copyright-year>2014</copyright-year><license><license-p>This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/</license-p></license></permissions><abstract><p>
 
 
   Gracilariopsis lemaneiformis is a widely reported species of marine red algae, with records from around the world. Particularly in Mexico, it has been recorded along the coasts of the Gulf of Mexico and the Mexican Caribbean as well as the Tropical Mexican Pacific; so, its current distribution on the Mexican coasts is disjunct. From its molecular characterization with COI-5P and rbcL sequences of specimens collected at sites in Mexico where this species has been most frequently recorded, our aim was to re-evaluate the current distribution of Gp. lemaneiformis on the Mexican coasts and discuss the taxonomic implications. Phylogenetic analysis, supported by DNA species delimitation methods, genetic distances and morphological comparisons, showed that the current disjunct distribution of Gp. lemaniformis in Mexico is a consequence of taxonomic misidentifications. From our results, Gp. lemaneiformis is the only species of the genus with a distribution in the Tropical Mexican Pacific, whereas Gp. tenuifrons is the only species with a distribution in the Gulf of Mexico and the Mexican Caribbean. Also, we propose that Gp. cata-luziana is to be merged with Gp. tenuifrons, while Gp. costarisensis is to be merged with Gp. lemaneiformis. 
 
</p></abstract><kwd-group><kwd>COI-5P</kwd><kwd> Cosmopolitan</kwd><kwd> Morphological Variation</kwd><kwd> &lt;i&gt;rbc&lt;/i&gt;L</kwd><kwd> Species Delimitation</kwd></kwd-group></article-meta></front><body><sec id="s1"><title>1. Introduction</title><p>Gracilariopsis E.Y. Dawson, with the type species Gp. sjoestedtii (Kylin) E.Y. Dawson, comprises 25 species currently accepted taxonomically [<xref ref-type="bibr" rid="scirp.98081-ref1">1</xref>]. The genus is widely distributed in tropical and subtropical waters through the world; it is distinguished from related genera by the absence of tubular nutritive cells connecting the gonimoblast to the pericarp, by the broad-based gonimoblast composed of small cells, and by the superficial arrangement of strictly cylindrical spermatangia [<xref ref-type="bibr" rid="scirp.98081-ref2">2</xref>]. Additionally, some species of this genus are commercially important because of the presence of polysaccharides, as agars, in their cell walls [<xref ref-type="bibr" rid="scirp.98081-ref3">3</xref>].</p><p>Gracilariopsis lemaneiformis (Bory) E. Y. Dawson, Acleto &amp; Foldvik was originally described by Bory (as Gigartina lemaneiformis) [<xref ref-type="bibr" rid="scirp.98081-ref4">4</xref>] from specimens collected at Paita, Peru, the type locality. Apparently, it is a cosmopolitan marine species, widely recorded around subtropical and tropical waters of the Atlantic, Indian and Pacific oceans [<xref ref-type="bibr" rid="scirp.98081-ref1">1</xref>]. Particularly in Mexico, where it is very abundant, it currently presents what appears to be a disjunct distribution with numerous records, based only on the morpho-species concept [<xref ref-type="bibr" rid="scirp.98081-ref3">3</xref>], along the Pacific and Atlantic coasts of Mexico [<xref ref-type="bibr" rid="scirp.98081-ref5">5</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref6">6</xref>]. Except for Gp. cata-luzina Gurgel, Fredericq &amp; J.N. Norris, described on the basis of specimens from Veracruz, and a doubtful record of Gp. tenuifrons (C.J. Bird &amp; E.C. Oliveira) Fredericq &amp; Hommersand for Tabasco [<xref ref-type="bibr" rid="scirp.98081-ref3">3</xref>], Gp. lemaneiformis is essentially the only species from this genus known for Gulf of Mexico (GM) and Mexican Caribbean (MC), whereas for the tropical Mexican Pacific coast (TMP), it is the only species recorded, mainly in Oaxaca and Chiapas [<xref ref-type="bibr" rid="scirp.98081-ref5">5</xref>]. Morphologically, Gracilariopsis lemaneiformis is characterized by cylindrical axes, up to 100 cm tall, one to a few irregularly branched, indeterminate axes arising from a discoid holdfast; axes of 0.5 mm diameter at the base, broadening to 1.3 mm diameter and tapering toward the apices, sparsely irregularly branched; pseudoparenchymatose organization composed by one or two layers of cortical cells, three to five layers of subcortical cells, and four or five medullary cells. Spermatangia superficial in indefinite sori; Cystocarps scattered over the axes and branches, slightly constricted at the base subsurface layers below [<xref ref-type="bibr" rid="scirp.98081-ref2">2</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref7">7</xref>].</p><p>As is true for most of species in the Gracilariaceae, Gracilariopsis lemaneiformis exhibits very low morphological variation and high characters overlapping with other species within the genus with which it shares a distribution [<xref ref-type="bibr" rid="scirp.98081-ref7">7</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref8">8</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref9">9</xref>]. Although molecularly all species of Gracilariopsis are clearly differentiated [<xref ref-type="bibr" rid="scirp.98081-ref2">2</xref>], their morphological delimitation has been complicated, leading to the uncovering of cryptic diversity or misidentifications, which has resulted in apparent cosmopolitan species [<xref ref-type="bibr" rid="scirp.98081-ref2">2</xref>]. Molecular-assisted α taxonomy has been successfully applied to the recognition of species [<xref ref-type="bibr" rid="scirp.98081-ref10">10</xref>], especially in problematic groups [<xref ref-type="bibr" rid="scirp.98081-ref9">9</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref11">11</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref12">12</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref13">13</xref>]. Particularly, in molecular studies realized from specimens previously recorded as Gp. lemaneiformis in other regions of the world, some misidentifications have been detected [<xref ref-type="bibr" rid="scirp.98081-ref2">2</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref14">14</xref>].</p><p>In a survey along the Mexican coast from TMP, GM and MC, we collected specimens morphologically related to Gp. lemaneiformis, mainly at sites where this species has been widely recorded [<xref ref-type="bibr" rid="scirp.98081-ref3">3</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref7">7</xref>]. From molecular sequences of the COI-5P and rbcL genes of these specimens, our aim was to re-evaluate the disjunct distribution of Gp. lemaneiformis on the Mexican coasts and discuss the taxonomic implications.</p></sec><sec id="s2"><title>2. Material and Methods</title><p>Samples morphologically identified as Gracilariopsis lemaneiformis were collected from different sites of the TMP, GM and MC coasts (<xref ref-type="table" rid="table">Table </xref>S1), where this species is abundant and widely recorded [<xref ref-type="bibr" rid="scirp.98081-ref3">3</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref5">5</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref6">6</xref>], at a depth of 0.5 - 1.5 m and sites with low waves. Apical sections for molecular analysis were preserved in silica gel until DNA extraction. Samples collected for morphological analysis were preserved in 6% formaldehyde in seawater. Fresh specimens were mounted on herbarium sheets and incorporated into the algal collections at Metropolitan Herbarium UAMIZ (Index Herbariorum http://sweetgum.nybg.org/science/ih/).</p><p>DNA for molecular analysis was extracted from 5 - 10 mg of dried tissue using a QIAGEN DNeasy Plant Mini Kit (Qiagen, Valencia, California USA) according to the manufacturer’s protocols. The mitochondrial COI-5P region was amplified using the primers GAZF1 and GAZR1 [<xref ref-type="bibr" rid="scirp.98081-ref15">15</xref>], and the chloroplast rbcL region was amplified using the primers F-rbcL-start, R753, F577, R1150, F993 and R-rbcS-start [<xref ref-type="bibr" rid="scirp.98081-ref16">16</xref>]. These markers were selected because of the number of sequences of Gracilariopsis available in GenBank, with which to compare our specimens. The PCR procedure followed Ardito et al. [<xref ref-type="bibr" rid="scirp.98081-ref12">12</xref>]. PCR products were purified with the QIAquick Gel Extraction (Qiagen) and commercially sequenced (Macrogen Inc., Seoul, Korea). The same set of primers was used for sequencing. The sequences generated were assembled and edited using the program Sequencher&#174; version 5.4.5. The final alignment, with sequences of other species of Gracilariopsis from GenBank (<xref ref-type="table" rid="table">Table </xref>S2 and <xref ref-type="table" rid="table">Table </xref>S3), was performed using SeaView [<xref ref-type="bibr" rid="scirp.98081-ref17">17</xref>]. Gracilaria isabellana Gurgel, Fredericq &amp; J.N. Norris and G. curtissiae J. Agardh were included as outgroups for the COI-5P data set, while G. curtissiae and G. domingensis (K&#252;tzing) Sonder ex Dickie were included as outgroups for the rbcL data set [<xref ref-type="bibr" rid="scirp.98081-ref18">18</xref>]. We analyzed the COI-5P and rbcL data sets separately. These DNA markers were chosen due to the high number of sequences available in GenBank. Phylogenetic analyses using Bayesian Inference (BI) and maximum likelihood (ML) were performed with codons partitioned. The evolutionary model selected for COI-5P and rbcL data sets was GTR+G+I (general time reversible + gamma distribution + invariable sites) determined by the ML ratio test implement by TOPALi v2 software [<xref ref-type="bibr" rid="scirp.98081-ref19">19</xref>]. ML analysis was performed using RAxML software [<xref ref-type="bibr" rid="scirp.98081-ref20">20</xref>] with the GTR+G+I model. Support for each branch was obtained from 1000 bootstrap replications. BI analysis was performed using Mr Bayes v3.2.2 [<xref ref-type="bibr" rid="scirp.98081-ref21">21</xref>]. Four chains of Markov chain Monte Carlo were used, starting with a random tree and sampling the data every 1000 generations for 5 &#215; 10<sup>6</sup> generations. 25% of trees were discarded as burn-in. Pairwise distances values (p distance) were calculated using Mega X [<xref ref-type="bibr" rid="scirp.98081-ref22">22</xref>].</p><p>To delimit Gracilariopsis species we ran three DNA-based species delimitations methods for both data sets (COI-5P and rbcL): Automatic Barcoding Gap Detection (ABGD) [<xref ref-type="bibr" rid="scirp.98081-ref23">23</xref>], the General-Mixed-Yule-Coalescent (GMYC) [<xref ref-type="bibr" rid="scirp.98081-ref24">24</xref>] and the Bayesian variant of Poisson Trees Processes model (bPTP) [<xref ref-type="bibr" rid="scirp.98081-ref25">25</xref>]. The ABGD delimited method was done via interface web (https://bioinfo.mnhn.fr/abi/public/abgd/abgdweb.html), with the following criteria: intraspecific variability (P) between 0.001 (Pmin) and 0.1 (Pmax), minimum gap width (X) of 0.1, Kimura-2-parameters and 50 screening steps. The bPTP model was done via interface web (https://species.h-its.org/ptp/), using the ML topology. The analysis consisted of 100,000 generations, with a thinning every 100 generations and a burn-in of 25%. For GYMC analyses, we generated an ultrametric tree for GYMC analyses in BEAST 1.8.2 software [<xref ref-type="bibr" rid="scirp.98081-ref26">26</xref>], from rbcL and COI-5P after removing identical sequences in the alignments. A coalescent constant size tree prior was set under an uncorrelated lognormal relaxed clock and GTR+G+I sites model. The analysis was set up for 10 million generations and a sampling frequency of 5000. Before performing the GMYC analyses, we checked the estimated samples size with Tracer 1.6 [<xref ref-type="bibr" rid="scirp.98081-ref27">27</xref>]. The maximum clade credibility tree was computed using TreeAnnotator 1.8.3 [<xref ref-type="bibr" rid="scirp.98081-ref26">26</xref>]. The resulting ultrametric tree was imported into the GMYC web server (https://species.h-its.org/gmyc/), running the single threshold.</p><p>For morphological identification and comparison of the specimens, microscopic cross-sections were made by hand using a razor blade and mounted in an 80% Karo&#174;/distilled water solution. Photomicrographs were taken using a Quasar digital camera attached to a Leica DMLB microscope (Heidelberg, Germany). Photographs were taken with a Nikon D7000 digital camera. Morphological measurements were obtained from micrographs using SigmaScan&#169;Pro automated image analysis software (Jandel Scientific, Sausalito, California).</p></sec><sec id="s3"><title>3. Results</title><p>The COI-5P alignment consisted of 35 sequences of 675 base pairs (bp) long, the rbcL alignment consisted of 48 sequences with 1241 pb long. In both analyses (<xref ref-type="fig" rid="fig">Figure </xref>S1 and <xref ref-type="fig" rid="fig">Figure </xref>1), the ML and BI trees did not differ, but there were some differences among markers, due to sampling and in poorly supported branches. In both analyses, the COI-5P and rbcL, sequences of Gracilariopsis formed a monophyletic group. The COI-5P analysis showed that our sequences (identified as Gracilariopsis lemaneiformis) formed two clades within the genus. Clade I, with strong support (ML = 97%, BI = 1.0), was composed of our sequences from TMP and sequences from GenBank identified as Gp. lemaneiformis from Ecuador (<xref ref-type="fig" rid="fig">Figure </xref>S1). Clade II, with the maximum support (ML = 100%, BI = 1.0), was composed of our sequences from GM and MC and sequences from GenBank identified as Gp. tenuifrons from Brazil and Venezuela (<xref ref-type="fig" rid="fig">Figure </xref>S1). With rbcL, our specimens (identified as Gp. lemaneiformis) were grouped into two clades (<xref ref-type="fig" rid="fig">Figure </xref>1). Clade I, with strong support (ML = 99%, BI =</p><p>1.0), was composed of our sequences from GM and MC and four sequences from GenBank (from Brazil, Guadeloupe and Venezuela) identified as Gp. tenuifrons. In turn Clade II, with strong support (ML = 82%, BI = 1.0) was differentiated into three sister subclades (subclades A, B and C), which were resolved as sister groups, also well supported (<xref ref-type="fig" rid="fig">Figure </xref>1). Subclade A was composed of our sequences from TMP and a sequence from GenBank (from Costa Rica) identified as Gp. costaricensis E.Y. Dawson; subclade B was composed of four sequences from GenBank (from Peru) identified as Gp. lemaneiformis; subclade C was composed of two sequences from GenBank (from Ecuador and Peru) identified as Gp. lemaneiformis.</p><p>The genetic p-distance values within our specimens from GM, MC and TMP ranged from 0 to 6.1% with COI-5P, and from 0 to 3.3%, with rbcL. On the contrary, there was no genetic variation with any marker (COI-5P and rbcL) between our specimens of Gracilariopsis lemaneiformis from GM and MC, or between specimens of TMP. However, between our specimens from MC and GM and sequences from Gp. tenuifrons from GenBank, genetic distances values ranged from 0 to 0.2%, with COI-5P, and from 0 to 0.1%, with rbcL. While our specimens from GM, MC and TMP and sequence from Gp. cata-luziana from GenBank, genetic distance values 1.7%. On the other hand, the genetic distance between our specimens from TMP and Gp. lemaneiformis from GenBank was 0.1%, with COI-5P; and genetic distance between our specimens from TMP, and Gp. costaricensis and Gp. lemaneiformis from GenBank ranged from 0.3 to 0.8%, with rbcL. Finally, the genetic distance between our specimens and other Gracilariopsis species ranged from 4.8% to 10.7%, with COI-5P, and from 1.7 to 7.5, with rbcL.</p><p>The DNA species delimitation with both markers, based on ABGD, bPTP and GYMC analyses, showed that our specimens from TMP and sequences of Gp. lemaneiformis and Gp. costarincensis from South America, correspond to only one species, while our specimens from MC, GM and sequences of Gp. tenuifrons from Brazil and Antilles also correspond to a single species (<xref ref-type="fig" rid="fig">Figure </xref>S1 and <xref ref-type="fig" rid="fig">Figure </xref>1).</p><p>A morphological comparison between our specimens from TMP, GM and MC (<xref ref-type="fig" rid="fig">Figure </xref>2) with Gp. tenuifrons, Gp. cata-luziana, Gp. lemaneiformis, and Gp. costaricencis is displayed in <xref ref-type="table" rid="table">Table </xref>1, considering only five variable vegetative characters between these species.</p><table-wrap id="table1" ><label><xref ref-type="table" rid="table">Table </xref>1</label><caption><title> Morphological comparison between our specimens of Gracilariopsis lemaneiformis used in this study and the species of closed related</title></caption><table><tbody><thead><tr><th align="center" valign="middle"  rowspan="2"  >Taxa</th><th align="center" valign="middle"  colspan="3"  >Characters</th><th align="center" valign="middle" ></th><th align="center" valign="middle" ></th></tr></thead><tr><td align="center" valign="middle" >Thallus length (cm)</td><td align="center" valign="middle" >Branch diameter (mm)</td><td align="center" valign="middle" >Number of medullary cells</td><td align="center" valign="middle" >Layers of subcortical cells</td><td align="center" valign="middle" >Layers of cortical cells</td></tr><tr><td align="center" valign="middle" >Gp. cata-luziana<sup>2</sup></td><td align="center" valign="middle" >up to 26 (−36)</td><td align="center" valign="middle" >0.4 - 0.5</td><td align="center" valign="middle" >1 - 5</td><td align="center" valign="middle" >1 - 2</td><td align="center" valign="middle" >2</td></tr><tr><td align="center" valign="middle" >Gp. costaricensis<sup>1,3</sup></td><td align="center" valign="middle" >up to 25</td><td align="center" valign="middle" >0.8</td><td align="center" valign="middle" >5 - 6</td><td align="center" valign="middle" >1 - 2</td><td align="center" valign="middle" >1 - 2</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis<sup>1,3</sup></td><td align="center" valign="middle" >up to 100</td><td align="center" valign="middle" >0.5 - 1.3</td><td align="center" valign="middle" >4 - 5</td><td align="center" valign="middle" >3 - 5</td><td align="center" valign="middle" >1 - 2</td></tr><tr><td align="center" valign="middle" >Gp. tenuifrons<sup>1</sup></td><td align="center" valign="middle" >up to 40</td><td align="center" valign="middle" >1.0</td><td align="center" valign="middle" >3 - 4</td><td align="center" valign="middle" >1 - 3</td><td align="center" valign="middle" >1 - 2</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis (TMP)<sup>4</sup></td><td align="center" valign="middle" >up to 95</td><td align="center" valign="middle" >0.3 - 0.5</td><td align="center" valign="middle" >4 - 6</td><td align="center" valign="middle" >1 - 2</td><td align="center" valign="middle" >1 - 2</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis (GM)<sup>4</sup></td><td align="center" valign="middle" >up to 35</td><td align="center" valign="middle" >0.5 - 0.7</td><td align="center" valign="middle" >6</td><td align="center" valign="middle" >1 - 2</td><td align="center" valign="middle" >2</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis (MC)<sup>4</sup></td><td align="center" valign="middle" >up to 35</td><td align="center" valign="middle" >0.5 - 1</td><td align="center" valign="middle" >3 - 4 (−6)</td><td align="center" valign="middle" >1 - 2</td><td align="center" valign="middle" >2</td></tr></tbody></table></table-wrap><p>TMP—Tropical Mexican Pacific; GM—Gulf of Mexico; MC—Mexican Caribbean. <sup>1</sup>Bird and Oliveira Filho [<xref ref-type="bibr" rid="scirp.98081-ref7">7</xref>], <sup>2</sup>Gurgel et al. [<xref ref-type="bibr" rid="scirp.98081-ref28">28</xref>], <sup>3</sup>Gurgel et al. [<xref ref-type="bibr" rid="scirp.98081-ref2">2</xref>] and <sup>4</sup>this study.</p></sec><sec id="s4"><title>4. Discussion</title><p>Phylogenetic analysis, supported by DNA species delimitation methods, genetic distances and morphological comparisons, showed that the current disjunct distribution of Gracilariopsis lemaneiformis in Mexico is a consequence of taxonomic misidentifications.</p><p>Since unfortunately the sequences of all the species discussed in the present study were not available with COI-5P, our discussion was particularly based on the phylogenetic analysis with rbcL, using the phylogeny with COI-5P mainly to reinforce the molecular identification of our specimens.</p><p>For GM and MC, in the phylogenetic tree all our specimens formed a monophyletic group with sequences of Gp. tenuifrons from Brazil and the Antilles (<xref ref-type="fig" rid="fig">Figure </xref>S1 and <xref ref-type="fig" rid="fig">Figure </xref>1). This species has been widely recorded in the Caribbean Sea, but, until now, it had not been recorded on the Mexican coasts, except a doubtful record for Tabasco [<xref ref-type="bibr" rid="scirp.98081-ref3">3</xref>]. In turn, this clade was resolved as the sister group of Gp. cata-luziana from its type locality in Veracruz (AY049406), another species morphologically very similar to Gp. tenuifrons [<xref ref-type="bibr" rid="scirp.98081-ref28">28</xref>]. According to the literature, morphologically both species overlap almost completely, the only difference being the diameter of the branches, which is greater in Gp. tenuifrons than in Gp. cata-luziana [<xref ref-type="bibr" rid="scirp.98081-ref7">7</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref28">28</xref>]. Our specimens from Veracruz, as described by Gurgel et al. [<xref ref-type="bibr" rid="scirp.98081-ref28">28</xref>] for Gp. cata-luziana, presented branches with smaller diameters than our specimens of the MC, whose diameters were related to what is described in the literature for Gp. tenuifrons (<xref ref-type="table" rid="table">Table </xref>1, <xref ref-type="fig" rid="fig">Figure </xref>2); however, there were no genetic differences between our GM and MC specimens. As for its distribution, the range known so far for both species was defined, for Gp. cata-luziana in the GM [<xref ref-type="bibr" rid="scirp.98081-ref28">28</xref>] and for Gp. tenuifrons in the MC [<xref ref-type="bibr" rid="scirp.98081-ref7">7</xref>]. According to Gurgel et al. [<xref ref-type="bibr" rid="scirp.98081-ref28">28</xref>], the present distribution of both species was the result of a vicariant event in the area due to the emergence of the Yucatan Peninsula, which culminated in the speciation process that gave rise to both species. Although interspecific genetic distance values 1.7% between Gp. tenuifrons and the sequence of Gp. cata-luziana from GenBank support their genetic independence, we believe that Gp. cata-luziana should be treated as a taxonomic synonym of Gp. tenuifrons. This statement is supported by our results that do not support the presence of Gp. cata-luziana in its current distribution range. The only rbcL sequence available in the GenBank (AY049406) for this species presented many alignment problems with the rest of the sequences of the species of the genus, due to the presence of numerous gaps or nucleotides that were not present in others related sequences. Additionally, since its original description, this species has not been recorded again in the region.</p><p>In the case of TMP, our specimens formed a major monophyletic group that in turn was subdivided into three sister subclades, subclade A grouping to our specimens from TMP with Gp. costaricensis from its type locality, subclade B grouping sequences of Gp. lemaneiformis from its type locality in Peru, and subclade C grouping sequences of Gp. lemaneiformis from Ecuador and Peru. From the descriptions in the literature, morphologically Gp. lemaneiformis and Gp. costaricensis differ from each other by the thallus length, diameters of branches and number of layers of subcortical cells [<xref ref-type="bibr" rid="scirp.98081-ref2">2</xref>] [<xref ref-type="bibr" rid="scirp.98081-ref7">7</xref>]. However, according to our observations both species are not morphologically different (<xref ref-type="table" rid="table">Table </xref>1, <xref ref-type="fig" rid="fig">Figure </xref>2), in that it is possible to find specimens of subclade A, which would genetically correspond to Gp. costaricensis, with characteristics of subclade B, genetically resolved as Gp. lemaneiformis, and the other way around (<xref ref-type="table" rid="table">Table </xref>1). On the other hand, our species delimitation analysis showed that both our TMP specimens and the sequences of Gp. costaricensis and Gp. lemaniformis are not genetically independent, but all make up a single genetic entity. As for its distribution, since Gp. lemaneiformis is still a cosmopolitan species in the world today [<xref ref-type="bibr" rid="scirp.98081-ref1">1</xref>], Gurgel et al. [<xref ref-type="bibr" rid="scirp.98081-ref28">28</xref>] and Arakaki et al. [<xref ref-type="bibr" rid="scirp.98081-ref14">14</xref>] proposed that the distribution of this species should be considered restricted to Peru and nearby sites, while records in other parts of the world should be re-evaluated. However, our results showed that our TMP specimens correspond both morphologically and genetically with Gp. lemaneiformis; so, the range of distribution of this species extends from Peru to Chiapas in the TMP. Although the rbcL interspecific genetic distance values between Gp. costaricensis and Gp. lemaneiformis were lower than interspecific values previously proposed by other authors in Gracilariaceae, namely. &gt;2% according to Gurgel and Fredericq [<xref ref-type="bibr" rid="scirp.98081-ref29">29</xref>] and 1.5% - 12.8% according to Muangmai et al. [<xref ref-type="bibr" rid="scirp.98081-ref11">11</xref>], what is not supported is independence between both species. However, the genetic variation between three subclades could correspond to specific varieties. Yet the current evidence allows us only to propose that both species should be merged. Future studies of a phylogeographic nature in combination with detailed morphometric analysis could provide more evidence for the establishment of taxa at the infraspecific level.</p><p>Although the taxonomic status of the remaining species of Gracilariopsis recorded in Mexico must be re-evaluated in detail, from our current results and the fact that these records are unique, doubtful and very old, or correspond to species whose distribution area has already been limited to certain regions of the world, such as Gp. megaspora E.Y. Dawson with its range restricted to the Indian Ocean [<xref ref-type="bibr" rid="scirp.98081-ref2">2</xref>], our analysis of the “disjunct distribution” of Gp. lemaneformis in Mexico allows us to suppose that Gp. tenuifrons is the only species of the genus distributed in GM and MC, while Gp. lemaneiformis is the most common species distributed in TMP.</p><p>Finally, we propose the following taxonomic changes:</p><p>Gracilariopsis lemaneiformis (Bory) E.Y. Dawson, Acleto &amp; Foldvik 1964: 59, pl. 56: fig. A [<xref ref-type="bibr" rid="scirp.98081-ref30">30</xref>].</p><p>Basionym: Gigartina lemaneiformis.</p><p>Heterotypic synonym: Gp. costaricensis E.Y. Dawson 1949 [<xref ref-type="bibr" rid="scirp.98081-ref31">31</xref>].</p><p>Type Locality: Paita, Peru.</p><p>Gracilariopsis tenuifrons (C.J. Bird et E.C. Oliveira) Fredericq &amp; Hommersand 1989: 240 [<xref ref-type="bibr" rid="scirp.98081-ref32">32</xref>].</p><p>Basionym: Gracilaria tenuifrons C.J. Bird &amp; E.C. Oliveira.</p><p>Heterotypic synonym: Gp. cata-luziana Gurgel, Fredericq &amp; J. Norris 2003 [<xref ref-type="bibr" rid="scirp.98081-ref28">28</xref>].</p><p>Type Locality: Praia Avenida, near Maceio, Alagoas, Brazil.</p></sec><sec id="s5"><title>Acknowledgements</title><p>First author thanks the Consejo Nacional para la Ciencia y Tecnolog&#237;a for the scholarship granted. This work was supported by the projects: UAMI-CBS2019-2022: session 15.18-281118 and UAMI-CA-117, PRODEP, and contains some results from the PhD project of Oscar E. Hern&#225;ndez in the Doctorado en Ciencias Biol&#243;gicas y de la Salud graduate program of the Universidad Aut&#243;noma Metropolitana.</p></sec><sec id="s6"><title>Conflicts of Interest</title><p>The authors declare no conflicts of interest regarding the publication of this paper.</p></sec><sec id="s7"><title>Cite this paper</title><p>Hernandez, O.E., Dreckmann, K.M., Nu&#241;ez-Resendiz, M.L., Vilchis, M.I. and Sent&#237;es, A. (2020) Gracilariopsis lemaneiformis (Gracilariaceae, Rhodophyta) in the Mexican Coasts: A Case of Disjunct Distribution? American Journal of Plant Sciences, 11, 111-124. https://doi.org/10.4236/ajps.2020.112009</p></sec><sec id="s8"><title>Supplementary</title><table-wrap id="table2" ><label><xref ref-type="table" rid="table">Table </xref>S1</label><caption><title> Specimens identified as Gracilariopsis lemaneiformis collected and sequenced (rbcL and COI-5P) in this study</title></caption><table><tbody><thead><tr><th align="center" valign="middle"  colspan="2"  >GenBank Accesion Number</th><th align="center" valign="middle"  rowspan="2"  >Locality</th><th align="center" valign="middle"  rowspan="2"  >Coordinates</th><th align="center" valign="middle"  rowspan="2"  >Collected Date</th><th align="center" valign="middle"  rowspan="2"  >Vaucher UAMIZ Herbarium</th></tr></thead><tr><td align="center" valign="middle" >rbcL</td><td align="center" valign="middle" >COI-5P</td></tr><tr><td align="center" valign="middle" >MK238056</td><td align="center" valign="middle" >MK238044</td><td align="center" valign="middle" >Boca del Cielo, Chiapas</td><td align="center" valign="middle" >15˚51'00&quot;N, 93˚40'00&quot;W</td><td align="center" valign="middle" >25/03/2018</td><td align="center" valign="middle" >UAMIZ1349#1</td></tr><tr><td align="center" valign="middle" >MK238057</td><td align="center" valign="middle" >MK238045</td><td align="center" valign="middle" >Boca del Cielo, Chiapas</td><td align="center" valign="middle" >15˚51'00&quot;N, 93˚40'00&quot;W</td><td align="center" valign="middle" >25/03/2018</td><td align="center" valign="middle" >UAMIZ1349#2</td></tr><tr><td align="center" valign="middle" >MK238058</td><td align="center" valign="middle" >MK238046</td><td align="center" valign="middle" >Boca del Cielo, Chiapas</td><td align="center" valign="middle" >15˚51'00&quot;N, 93˚40'00&quot;W</td><td align="center" valign="middle" >25/03/2018</td><td align="center" valign="middle" >UAMIZ1349#3</td></tr><tr><td align="center" valign="middle" >MK238059</td><td align="center" valign="middle" >MK238047</td><td align="center" valign="middle" >Boca del Cielo, Chiapas</td><td align="center" valign="middle" >15˚51'00&quot;N, 93˚40'00&quot;W</td><td align="center" valign="middle" >25/03/2018</td><td align="center" valign="middle" >UAMIZ1350#1</td></tr><tr><td align="center" valign="middle" >MK238060</td><td align="center" valign="middle" >MK238048</td><td align="center" valign="middle" >Boca del Cielo, Chiapas</td><td align="center" valign="middle" >15˚51'00&quot;N, 93˚40'00&quot;W</td><td align="center" valign="middle" >25/03/2018</td><td align="center" valign="middle" >UAMIZ1350#2</td></tr><tr><td align="center" valign="middle" >MK238061</td><td align="center" valign="middle" >MK238049</td><td align="center" valign="middle" >Boca del Cielo, Chiapas</td><td align="center" valign="middle" >15˚51'00&quot;N, 93˚40'00&quot;W</td><td align="center" valign="middle" >25/03/2018</td><td align="center" valign="middle" >UAMIZ1350#3</td></tr><tr><td align="center" valign="middle" >MK238062</td><td align="center" valign="middle" >MK238050</td><td align="center" valign="middle" >Playa Tibur&#243;n, Isla Mujeres, Quintana Roo</td><td align="center" valign="middle" >21˚13'23&quot;N, 86˚44'00&quot;W</td><td align="center" valign="middle" >18/12/2013</td><td align="center" valign="middle" >UAMIZ1351#1</td></tr><tr><td align="center" valign="middle" >MK238063</td><td align="center" valign="middle" >MK238051</td><td align="center" valign="middle" >Playa Tibur&#243;n, Isla Mujeres, Quintana Roo</td><td align="center" valign="middle" >21˚13'23&quot;N, 86˚44'00&quot;W</td><td align="center" valign="middle" >18/12/2013</td><td align="center" valign="middle" >UAMIZ1351#2</td></tr><tr><td align="center" valign="middle" >MK238064</td><td align="center" valign="middle" >MK238052</td><td align="center" valign="middle" >Playa El Ni&#241;o, Canc&#250;n, Quintana Roo</td><td align="center" valign="middle" >21˚11'37&quot;N, 86˚48'20&quot;W</td><td align="center" valign="middle" >20/05/2017</td><td align="center" valign="middle" >UAMIZ1352</td></tr><tr><td align="center" valign="middle" >MK238065</td><td align="center" valign="middle" >MK238053</td><td align="center" valign="middle" >Costa de Oro, Veracruz</td><td align="center" valign="middle" >19˚09'08&quot;N, 96˚05'40&quot;W</td><td align="center" valign="middle" >02/07/2015</td><td align="center" valign="middle" >UAMIZ1353#1</td></tr><tr><td align="center" valign="middle" >MK238066</td><td align="center" valign="middle" >MK238054</td><td align="center" valign="middle" >Costa de Oro Veracruz</td><td align="center" valign="middle" >19˚09'08&quot;N, 96˚05'40&quot;W</td><td align="center" valign="middle" >02/07/2015</td><td align="center" valign="middle" >UAMIZ1353#2</td></tr><tr><td align="center" valign="middle" >MK238067</td><td align="center" valign="middle" >MK238055</td><td align="center" valign="middle" >Playa Gaviota, Veracruz</td><td align="center" valign="middle" >19˚08'34&quot;N, 96˚06'01&quot;W</td><td align="center" valign="middle" >20/10/2015</td><td align="center" valign="middle" >UAMIZ1354</td></tr></tbody></table></table-wrap><table-wrap id="table3" ><label><xref ref-type="table" rid="table">Table </xref>S2</label><caption><title> Sequences of rbcL from GenBank used in the alignment</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Specie</th><th align="center" valign="middle" >Geographic Information</th><th align="center" valign="middle" >Accession number</th></tr></thead><tr><td align="center" valign="middle"  colspan="3"  >Outgroup</td></tr><tr><td align="center" valign="middle" >G. curtissiae J. Agardh</td><td align="center" valign="middle" >La Encrucijada, Venezuela</td><td align="center" valign="middle" >AY049333</td></tr><tr><td align="center" valign="middle" >G. dominguensis (K&#252;tzing) Sonder ex Dickie</td><td align="center" valign="middle" >Bahia, Urucuca, Serra Grande, Brazil</td><td align="center" valign="middle" >KP210223</td></tr><tr><td align="center" valign="middle"  colspan="3"  >Ingroup</td></tr><tr><td align="center" valign="middle" >Gracilariopsis andersonii (Grunow) E. Y. Dawson</td><td align="center" valign="middle" >Gwaii Haanas, Ramsey Island, British Island, Canada</td><td align="center" valign="middle" >KU382057</td></tr><tr><td align="center" valign="middle" >Gp. carolinensis L. M. Liao &amp; Hommersand</td><td align="center" valign="middle" >Wilmington, North Carolina, USA</td><td align="center" valign="middle" >AY049412</td></tr><tr><td align="center" valign="middle" >Gp. cata-luziana Gurgel, Fredericq &amp; J. N. Norris</td><td align="center" valign="middle" >Anton Lizardo, Veracruz, Gulf of Mexico, Mexico</td><td align="center" valign="middle" >AY049406</td></tr><tr><td align="center" valign="middle" >Gp. changii S.-M. Lin</td><td align="center" valign="middle" >Sail Rock, Kenting National Park, Taiwan</td><td align="center" valign="middle" >DQ119746</td></tr><tr><td align="center" valign="middle" >Gp. chorda (Holmes) Ohmi</td><td align="center" valign="middle" >Awaji Island, Japan</td><td align="center" valign="middle" >FJ235527</td></tr><tr><td align="center" valign="middle" >Gp. chorda</td><td align="center" valign="middle" >Jindo, Hoidong, South Korea</td><td align="center" valign="middle" >DQ095785</td></tr><tr><td align="center" valign="middle" >Gp. chorda</td><td align="center" valign="middle" >Shimoda, Shizouka</td><td align="center" valign="middle" >EU567347</td></tr><tr><td align="center" valign="middle" >Gp. costaricensis E. Y. Dawson</td><td align="center" valign="middle" >Guanacaste, Nicoya Peninsula, southern of Playa Tamarindo, Costa Rica</td><td align="center" valign="middle" >AY049423</td></tr><tr><td align="center" valign="middle" >Gp. funicularis Iyer, Bolton &amp; Coyne</td><td align="center" valign="middle" >Swakopsmund, Namibia</td><td align="center" valign="middle" >AY049410</td></tr><tr><td align="center" valign="middle" >Gp. heteroclada J.-F. Zhang &amp; B.-M. Xia</td><td align="center" valign="middle" >Dapdap, Bulusan, Luzon, Phillipines</td><td align="center" valign="middle" >AY049411</td></tr><tr><td align="center" valign="middle" >Gp. heteroclada</td><td align="center" valign="middle" >Hainan, China</td><td align="center" valign="middle" >JQ026028</td></tr><tr><td align="center" valign="middle" >Gp. hommersandii Gurgel, Fredericq &amp; J. N. Norris</td><td align="center" valign="middle" >Los Roques Archipelago, Los Francisky Island, Venezuela</td><td align="center" valign="middle" >AY049408</td></tr><tr><td align="center" valign="middle" >Gp. irregularis (I. A. Abbott) N. Muangmai, A. Chirapart &amp; A. Lewmanomont</td><td align="center" valign="middle" >Ao Len, Trat Province, Thailand</td><td align="center" valign="middle" >KC465784</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis (Bory de Saint-Vincent) E. Y. Dawson, Acleto &amp; Foldvik</td><td align="center" valign="middle" >Guandong, China</td><td align="center" valign="middle" >JQ407670</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis</td><td align="center" valign="middle" >Guandong, China</td><td align="center" valign="middle" >JQ407672</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis</td><td align="center" valign="middle" >Guandong, China</td><td align="center" valign="middle" >JQ407673</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis</td><td align="center" valign="middle" >Eten, Chiclayo, Lambayeque, Peru</td><td align="center" valign="middle" >KP857574</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis</td><td align="center" valign="middle" >Ancon, Lima, Peru</td><td align="center" valign="middle" >KP857576</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis</td><td align="center" valign="middle" >Ancon, Lima, Peru</td><td align="center" valign="middle" >EU158089</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis</td><td align="center" valign="middle" >Yacilla, Paita, Piura, Peru</td><td align="center" valign="middle" >AY049415</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis</td><td align="center" valign="middle" >San Andres, Pisco, Ica, Peru</td><td align="center" valign="middle" >KP857575</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis</td><td align="center" valign="middle" >Ecuador</td><td align="center" valign="middle" >JQ843363</td></tr><tr><td align="center" valign="middle" >Gp. longissima (S. G. Gmelin) Steentoft, L. M. Irvine &amp; Farnham</td><td align="center" valign="middle" >Le Theven, Santec, France</td><td align="center" valign="middle" >DQ241579</td></tr><tr><td align="center" valign="middle" >Gp. longissima</td><td align="center" valign="middle" >Venetian Lagoon, Italy</td><td align="center" valign="middle" >AY049404</td></tr><tr><td align="center" valign="middle" >Gp. longissima</td><td align="center" valign="middle" >United Kingdom</td><td align="center" valign="middle" >JQ843364</td></tr><tr><td align="center" valign="middle" >Gp. mclachlanii Buriyo, Bellorin &amp; M. C. Oliveira</td><td align="center" valign="middle" >Pangamkungu, Tanzania</td><td align="center" valign="middle" >EU158092</td></tr><tr><td align="center" valign="middle" >Gp. megaspore E. Y. Dawson</td><td align="center" valign="middle" >South Australia, Robe, Lake Buttler, Australia</td><td align="center" valign="middle" >AY049422</td></tr><tr><td align="center" valign="middle" >Gp. nhatrangensis NhuHau Le &amp; S.-M. Lin</td><td align="center" valign="middle" >Nhatrang City, Vietnam</td><td align="center" valign="middle" >DQ119744</td></tr><tr><td align="center" valign="middle" >Gp. persica Bellorin, Sohrabipour &amp; E. C. Oliveira</td><td align="center" valign="middle" >Bandarabbas, Persian Gulf, Iran</td><td align="center" valign="middle" >EU158094</td></tr><tr><td align="center" valign="middle" >Gp. silvana Gurgel, Fredericq &amp; J. N. Norris</td><td align="center" valign="middle" >La Vela de Coro, Falcon State, Venezuela</td><td align="center" valign="middle" >AY049309</td></tr><tr><td align="center" valign="middle" >Gp. tenuifrons (C. J. Bird &amp; E. C. Oliveira) Fredericq &amp; Hommersand</td><td align="center" valign="middle" >La Pena, Araya, Venezuela</td><td align="center" valign="middle" >JQ843368</td></tr><tr><td align="center" valign="middle" >Gp. tenuifrons</td><td align="center" valign="middle" >Alagoas, Maceio, Lago de Mundau, Brazil</td><td align="center" valign="middle" >JQ843367</td></tr><tr><td align="center" valign="middle" >Gp. tenuifrons</td><td align="center" valign="middle" >Ilet Caret, Guadeloupe, French West Indies</td><td align="center" valign="middle" >AY049418</td></tr><tr><td align="center" valign="middle" >Gp. tenuifrons</td><td align="center" valign="middle" >Arya Peninsula, Sucre, Venezuela</td><td align="center" valign="middle" >AY049417</td></tr></tbody></table></table-wrap><table-wrap id="table4" ><label><xref ref-type="table" rid="table">Table </xref>S3</label><caption><title> Sequences of COI-5P from GenBank used in the alignment</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Specie</th><th align="center" valign="middle" >GeographicInformation</th><th align="center" valign="middle" >Number Accession</th></tr></thead><tr><td align="center" valign="middle"  colspan="3"  >Outgroup</td></tr><tr><td align="center" valign="middle" >G. curtissiae J. Agardh</td><td align="center" valign="middle" >Rio Grande do Norte, Diogo Lopes, Brazil</td><td align="center" valign="middle" >KP210166</td></tr><tr><td align="center" valign="middle" >G. isabellana Gurgel, Fredericq &amp; J. N. Norris</td><td align="center" valign="middle" >Sao Paulo, Ubatuba, Brazil</td><td align="center" valign="middle" >KP210185</td></tr><tr><td align="center" valign="middle"  colspan="3"  >Ingroup</td></tr><tr><td align="center" valign="middle" >Gp. andersonii (Grunow) E. Y. Dawson</td><td align="center" valign="middle" >California, Bird Rock, Pacific Grove, USA</td><td align="center" valign="middle" >KM254615</td></tr><tr><td align="center" valign="middle" >Gp. andersonii</td><td align="center" valign="middle" >California, Santa Cruz, USA</td><td align="center" valign="middle" >KM254410</td></tr><tr><td align="center" valign="middle" >Gp. andersonii</td><td align="center" valign="middle" >British Columbia, Canada</td><td align="center" valign="middle" >FJ499624</td></tr><tr><td align="center" valign="middle" >Gp. andersonii</td><td align="center" valign="middle" >British Columbia, Canada</td><td align="center" valign="middle" >FJ499625</td></tr><tr><td align="center" valign="middle" >Gp. chorda (Holmes) Ohmi</td><td align="center" valign="middle" >Misaki, Japan</td><td align="center" valign="middle" >HQ322072</td></tr><tr><td align="center" valign="middle" >Gp. chouae Zhang &amp; B. M. Xia</td><td align="center" valign="middle" >Guandong, China</td><td align="center" valign="middle" >JQ407613</td></tr><tr><td align="center" valign="middle" >Gp. funicularis Iyer, Bolton &amp; Coyne</td><td align="center" valign="middle" >Senegal</td><td align="center" valign="middle" >KP210200</td></tr><tr><td align="center" valign="middle" >Gp. funicularis</td><td align="center" valign="middle" >Senegal</td><td align="center" valign="middle" >KP210201</td></tr><tr><td align="center" valign="middle" >Gp. heteroclada J.-F. Zhang &amp; B.-M. Xia</td><td align="center" valign="middle" >Prieto Diaz, Sorsogon, Phillippines</td><td align="center" valign="middle" >KT779912</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis (Bory de Saint-Vincent) E. Y. Dawson, Acleto &amp; Foldvik</td><td align="center" valign="middle" >Guangdong, China</td><td align="center" valign="middle" >JQ407623</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis</td><td align="center" valign="middle" >Guangdong, China</td><td align="center" valign="middle" >JQ407630</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis</td><td align="center" valign="middle" >Ecuador</td><td align="center" valign="middle" >JQ843342</td></tr><tr><td align="center" valign="middle" >Gp. lemaneiformis</td><td align="center" valign="middle" >Hawaii</td><td align="center" valign="middle" >HQ422689</td></tr><tr><td align="center" valign="middle" >Gp. longissima (S. G. Gmelin) Steentoft, L. M. Irvine &amp; Farnham</td><td align="center" valign="middle" >United Kingdom</td><td align="center" valign="middle" >JQ843344</td></tr><tr><td align="center" valign="middle" >Gp. longissima</td><td align="center" valign="middle" >Lake Ganzirri, Messina, Italy</td><td align="center" valign="middle" >KF714855</td></tr><tr><td align="center" valign="middle" >Gp. silvana Gurgel, Fredericq &amp; J. N. Norris</td><td align="center" valign="middle" >Rio Grande do Norte, Praia de Ponta Negra, Brazil</td><td align="center" valign="middle" >KP210202</td></tr><tr><td align="center" valign="middle" >Gp. silvana</td><td align="center" valign="middle" >Espirito Santo, Meaipe, Brazil</td><td align="center" valign="middle" >KP210205</td></tr><tr><td align="center" valign="middle" >Gp. tenuifrons (C. J. Bird &amp; E. C. Oliveira) Fredericq &amp; Hommersand</td><td align="center" valign="middle" >La Pena, Arraya, Venezuela</td><td align="center" valign="middle" >JQ843351</td></tr><tr><td align="center" valign="middle" >Gp. tenuifrons</td><td align="center" valign="middle" >La Pena, Arraya, Venezuela</td><td align="center" valign="middle" >JQ843346</td></tr><tr><td align="center" valign="middle" >Gp. tenuifrons</td><td align="center" valign="middle" >Sao Paulo, Itanhaem, Brazil</td><td align="center" valign="middle" >JQ843349</td></tr><tr><td align="center" valign="middle" >Gp. tenuifrons</td><td align="center" valign="middle" >Rio de Janeiro, Cabo Frio, Brazil</td><td align="center" valign="middle" >JQ843354</td></tr></tbody></table></table-wrap></sec></body><back><ref-list><title>References</title><ref id="scirp.98081-ref1"><label>1</label><mixed-citation publication-type="other" xlink:type="simple">Guiry, M.D. and Guiry, G.M. (2019) AlgaeBase. World-Wide Electronic Publication. 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