Notes on marine algae in the International Biosphere Reserve Seaflower, Caribbean Colombia, VII: Additions to the benthic flora of San Andrés Island

2018·1.2 MB·English

by  Rincón-Díaz, M Natalia

Botany doi: https://dx.doi.org/10.1544 6/caldasia.v40n1.64597
http://www.revistas.unal.edu.co/index.php/cal Caldasia 40(1):97-111. Enero-junio 2018
Notes on marine algae in the International Biosphere
Reserve Seaflower, Caribbean Colombia, VII: Additions
to the benthic flora of San Andrés Island
Notas sobre las algas marinas de la Reserva Internacional de Biosfera
Seaflower, Caribe Colombiano, VII: adiciones a la flora bentónica
de la isla de San Andrés
M. nataLIa RInCÓn-DÍaZ1, BRIGIttE GaVIo1, 2*, MICHaEL J. WynnE3, aDRIana
SantoS-MaRtÍnEZ1
1Universidad Nacional de Colombia (Sede Caribe). CECIMAR. Circunvalar San Luis Free Town
# 52-44, San Andrés Isla, Colombia. [email protected]*
2Universidad Nacional de Colombia (sede Bogotá). Facultad de Ciencias, Departamento de Biología.
Cra 30 # 45 - 03, Bogotá, Colombia.
3University of Michigan Herbarium, Ann Arbor, MI 48108, USA
*Corresponding author.
ABSTRACT
Ten species of red macroalgae are newly reported for the Seaflower International Biosphere
Reserve in the Caribbean Sea. Of these taxa, four have been previously reported for the
Colombian Caribbean: Dohrniella antillarum, Halydictyon mirabile, Taenioma nanum,
and Aglaothamnion cordatum. The remaining six species are new records for the country:
Callithamniella tingitana, Frikkiella searlesii, Lejolisia exposita, Melanothamnus gorgoniae,
Monosporus indicus, and Wrangelia gordoniae. The algal material was collected in coral reef
habitats (9–17 m depth), and all species but one are diminutive algae growing mostly on coral
rubble or as epiphytes on larger algae. Their morphological features are discussed.
Key Words. Caribbean, Colombia, Frikkiella, red algae, Wrangelia, Callithamniella,
Lejolisia, Melanothamnus, Monosporus.
RESUMEN
Se presentan diez nuevos reportes de especies de macroalgas rojas para la Reserva
Internacional de la Biosfera Seaflower en el Mar Caribe. Cuatro taxones fueron previamente
citados para el Caribe colombiano: Dohrniella antillarum, Halydictyon mirabile, Taenioma
nanum y Aglaothamnion cordatum. Las restantes seis especies son nuevos registros para
el país: Callithamniella tingitana, Frikkiella searlesii, Lejolisia exposita, Melanothamnus
gorgoniae, Monosporus indicus y Wrangelia gordoniae. Todas las algas fueron colectadas
en hábitat de arrecife coralino (9–17 m de profundidad), y todas las especies menos una
son algas de tamaño diminuto, creciendo principalmente sobre coral muerto o como epifitas
de algas más grandes. Se discuten las características morfológicas y reproductivas de cada
especie, así como las novedades de su distribución.
Palabras Clave. Algas rojas, Caribe, Colombia, Frikkiella, Wrangelia, Callithamniella,
Lejolisia, Melanothamnus, Monosporus.
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Additions to the marine flora of San Andrés
INTRODUCTION rapid ecological evaluations to determine
the composition and abundance of the most
San Andres Island is part of the International representative groups of marine biota. For
Biosphere Reserve Seaflower, one of the macroalgae, they recorded 16 species of
the largest marine reserves in the world brown algae, 22 of green algae, and 23
(CORALINA-INVEMAR 2012); however, of red algae, and several cyanobacterial
the marine flora of the island has historically morphotypes. Their results included seven
received little attention (Albis-Salas and new records for Colombia and for the
Gavio 2011). Recently, collections of International Reserve Seaflower: Caulerpa
macroalgae have been undertaken in the lanuginosa J. Agardh, Caulerpa paspaloides
whole archipelago, revealing a flora much var. laxa Weber-van Bosse, Jania cubensis
more diverse than previously appreciated Montagne ex Kützing, Gracilaria cornea
(Albis-Salas and Gavio 2011, Ortiz and J. Agardh, Chamaedoris peniculum (J.
Gavio 2012, Reyes-Gómez et al. 2013, Ellis and Solander) Kuntze, Cladophora
Gavio et al. 2013, Barrera et al. 2016, Reyes- prolifera (Roth) Kützing, and Hydrolithon
Gómez and Gavio 2017). chamaedoris (Foslie and M. Howe)
M.J. Wynne.
In 2003, Díaz-Pulido and Díaz-Ruiz presented
an updated list of macroalgae for the Caribbean Gavio et al. (2015) published a list of
coast of Colombia, including a total of 565 taxa, species collected in the northern key of
201 of which were reported for the Archipelago the archipelago, specifically at Quitasueño,
of San Andres, Old Providence, and Santa also known as Queena Reef. A total of 75
Catalina. From 2011 to date, phycological taxa were listed: 14 were new records for
studies have been resumed in the archipelago: Colombia and nine new records for the
Albis-Salas and Gavio (2011) included six archipelago. Albis-Salas and Gavio (2015)
new records of red epiphytic algae, growing reported nine species as new records for the
over Thalassia testudinum K.D. Koenig. Archipelago, all found growing as epiphytes
Ortíz and Gavio (2012) listed 80 macroalgae on Thalassia testudinum.
species, reporting 23 as new records, 17 for
the archipelago and six for Colombia. Reyes- Rincón-Díaz et al. (2016) found as a new
Gómez et al. (2013) recorded seven species of record for the Western Atlantic the species
Cyanobacteria, of which five were new records Griffithsia capitata Børgesen, originally
for Colombia. Additionally, Gavio et al. (2013) reported exclusively from Macaronesia.
described a new species for science, Crouania Barrera et al. (2016), exploring the intertidal
pumila B. Gavio, V.P. Reyes-Gómez & M.J. rocky shore habitats associated with the
Wynne, which was found in samples taken at mollusk Cittarium pica (Linneaus, 1758)
different coastal ecosystems of the archipelago. on San Andrés Island, reported 25 new
Rincón-Díaz et al. (2014) reported a new records, 16 for Colombia and nine for the
record of the red alga for Colombia, Ceramium Archipelago. Finally, Reyes-Gómez and
bisporum D.L. Ballantine, exhibiting variation Gavio (2017) reported two new records of
in reproductive structures from the original brown algae for Old Providence Island.
description.
To date, the list of species of seaweed
Vega-Sequeda et al. (2015) explored registered for the archipelago includes a total
the northernmost ocean reef complex of of 303 taxa. Most of these species are small
Colombian Caribbean: Bajo Alicia cay filaments or filiform in morphology and
(Joint Regime Area between Colombia and difficult to detect and to identify, although
Jamaica) and Serranilla cay, where they made they appear abundant and are epiphytes of
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larger algae or seagrasses. These findings 2008). Slide material was mounted in 50 %
reveal the high diversity of benthic flora in glycerin, with previous staining in aniline-
the Archipelago and the need to continue blue solution. All specimens were deposited
exploring for them. in COL, the Herbarium of the Universidad
Nacional de Colombia. Information on type
To complete the biodiversity study of the localities and nomenclature was obtained
International Biosphere Reserve Seaflower, from Dr. Paul C. Silva’s Index Nominum
we discuss our recent findings on 10 species, Algarum (Silva c2017) and AlgaeBase
four of which are new records for the (Guiry and Guiry c2017).
Archipelago and the other six new for the
Colombian Caribbean.
MATERIALS AND METHODS
San Andrés (12°28’ North; 81°40’ West) is an
oceanic island of coral origin located in the
southwestern Caribbean, Colombia (Fig. 1).
The island has, on the eastern side, a barrier
reef running parallel to the coast, which
encloses a shallow lagoon. The western side
is characterized by two submerged terraces,
parallel to the coastline: one terrace is shallow
(4–10 m depth), while the second is deeper (10–
20 m depth) (Chaves-Fonnegra et al. 2007).
All the specimens were collected randomly by
SCUBA diving over the coral reef formations
on the western side of the island, at the localities
“Wild Life” (12°30’30” North; 81°43’45”
West) and “Green Moon” (12°29’07” North;
81°44’01” West), at depths ranging from 9–17
m. This sector is characterized by a reef terrace
with coral mat formations starting at a depth of
9 m, characterized by high species diversity of
Figure 1. San Andrés Island with sampling sites.
corals, sponges, octocorals, and algae (Díaz et
Wild Life (12°30’30” North; 81°43’45” West).
al. 2000).
Green Moon (12°29 07” North; 81°44′01” West).
Sampling was carried out during the
rainy (from November 2012 to January RESULTS AND DISCUSSION
2013 and June 2013 to August 2013) and
dry season (from February 2013 to May We listed and commented on a total of 10
2013). The algae were collected by hand new records of red algae found attached to
and then preserved in a 4 % formalin/ coral rubble or epiphytic on larger algae.
seawater solution. In the laboratory, algae Callithamniella tingitana, Frikkiella
were identified using an OLYMPUS BX51 searlesii, Lejolisia exposita, Melanothamnus
optical microscope (Olympus, Tokyo, gorgoniae, Monosporus indicus, and
Japan) with specific literature for species Wrangelia gordoniae are new records for
identification such as Taylor (1960), Littler Colombia (**). Dohrniella antillarum,
and Littler 2000, and Dawes and Mathieson Halydictyon mirabile, Taenioma nanum, and
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Additions to the marine flora of San Andrés
Aglaothamnion cordatum are new records throughout, attached to the substrate by
for the archipelago (*). descending multicellular rhizoidal filaments
(Fig. 2b). Main axis 50–110 µm in diameter,
RHODOPHYTA tapering distally; cells 180–250 µm long
(Fig. 2a). Branchlets alternate and radial,
Order Ceramiales composed of cells 15–20 µm in diameter and
Family Callithamniaceae up to 125 µm long. Apical cells of secondary
Aglaothamnion cordatum* (Børgesen) branchlets are longer and obtuse, 4 µm in
Feldmann-Mazoyer Figs 2a-b diameter and 7.5 µm in length, and basal cell
Type locality: Virgin Islands, Caribbean Sea. 50 µm diameter and 120 µm in length. Basal
portion formed by multicellular rhizoids with
Specimens observed: San Andrés Island: haptera (Fig. 2b). No reproductive structures
Wild Life: 02/IX/2012, depth 13 m; were observed. All specimens were found
22/I/2013, depth 17 m; 4/IV/2013, depth 13 growing as epiphytes on Canistrocarpus
m; 7/VI/2013, depth 10 m; 09/VIII/2013, cervicornis (Kützing) De Paula et De Clerck,
depth 10 m. Green Moon: 6/II/2013, depth Dictyota pulchella Hörnig et Schnetter,
12 m; 2/IV/2013, depth 9 m. All specimens Lobophora variegata (J.V. Lamouroux)
were in a vegetative stage. Specimen Womersley ex E.C. Oliveira, and Halimeda
collected at Green Moon, 6/II/2013, opuntia (Linnaeus) J.V. Lamouroux.
deposited at COL (COL 602242).
Remarks: To date, there are 28 species of
Thallus filamentous, erect, delicate (Fig. 2a), Aglaothamnion taxonomically accepted
up to 5 cm high; uniseriate main axes ecorticate (Guiry and Guiry c2017). Most species are
a b c
d e f g h
Figure 2. Habit of species reported from the International Biosphere Reserve Seaflower. Aglaothamnion
cordatum: a. Principal branches, b. Detail of rhizoids with haptera (arrowhead). Callithamniella
tingitana: c. Habit with detail of prostrate axis and multicellular rhizoids (arrowhead). d. Erect and
alternate branches bearing glandular cells, e. Detail of glandular cells (arrowhead) located in the last
dichotomy of the branches. Dohrniella antillarum: f. Habit and detail of erect axes, g. Main branch
bear alternately decumbent branchlets with papilliform cells (arrowhead). h. Detail of basal cells of
branches and papilliform cells. Scale bar: a, b, c and f = 200 µm; d, g and h= 100 µm; e= 50 µm.
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differentiated by the presence or absence of Specimens observed: San Andrés Island:
rhizoidal cortication, the branchlet disposition Green Moon: 12/VIII/2013, depth 12 m,
and the shape of carposporophytes. In the vegetative specimen.
tropical and subtropical Western Atlantic, there
are 11 recognized species of Aglaothamnion Very small algae (up to 1 mm), epiphytic
(Wynne 2017). Aglaothamnion collinsii on Halimeda tuna (J. Ellis & Solander) J.V
Aponte, Ballantine & Norris, A. felipponei Lamouroux. Branched thallus with prostrate
Aponte, Ballantine & Norris, A. herveyi and erect uniseriate axes (Fig. 2c). Prostrate
(Howe) Aponte, Ballantine & Norris and axis consisting of cells that are 70–80 µm
A. priceanum Maggs, Guiry & Rueness are in diameter and 110–135 µm in length.
easily distinguishable from our specimen From these cells originate either a rhizoid
because they are corticated. A. gallicum, A. or an erect axis. Rhizoids are multicellular,
halliae (Collins) Aponte, Ballantine & Norris, with lobate haptera. The axial cells in the
A. roseum (Roth) Maggs & L’Hardy-Halos middle thallus are about 68 µm in diameter
and A. uruguayense (W. R. Taylor) N. E. and 80 µm in length. Apical cells are 15–25
Aponte, D. L. Ballantine & J. N. Norris have µm in diameter and 30–60 µm in length.
distichous branching, while our specimen has Determinate erect axis with 1–2 orders
radially distributed branchlets. We can also of branches made up of cylindrical cells
discard A. boergesenii (Aponte & Ballantine) of 20 µm diameter at the base, and 50 µm
L’Hardy-Halos & Rueness because of its long; these branches have dichotomous to
coarser habit: according to the original pseudodichotomous divisions. Cells of the
description (Aponte and Ballantine 1990, as erect branches with 15 µm diameter at the
Callithamnion boergesenii) the main axis is apex and 25 µm long. Divisions of branches
160–220 µm in diameter, while our specimens have small basal cells of 15 µm in diameter
are in the range of 50–110 µm in diameter. and 15 µm in length near the apex; these
cells have a 6.5 µm diameter and a 7.5 µm
The remaining species, A. cordatum and in length (Fig. 2d). The specimens observed
A. flexibile (Collins) Aponte, Ballantine & had few inconspicuous glandular cells that
Norris share many characters. However, are usually located in the last dichotomy of
they are easily distinguishable by the shape the branches. These gland cells are 5–7 µm
of carposporophytes, and the overall shape in diameter, are located at one end of the
of the apices, which are distinctly flat topped cells and are in contact with just one cell
in A. flexibile and pyramidal in A. cordatum. of the branch (Fig. 2e). No reproductive
In the absence of reproductive structures, structures were observed.
the apex outline in our specimens fits the
description of A. cordatum. The species has Remarks: The genus Callithamniella was
been previously reported for the continental described by Feldmann-Mazoyer (1938),
coast of Colombia, for the National Natural based on the species Callithamnion tingitana
Park Tayrona (near the town of Santa Marta) Schousboe ex Bornet (1892). Later,
and for the Darien region, close to the border Feldmann-Mazoyer (1941) provided a more
with Panama. detailed description, depicting the creeping
axes giving rise to erect axes, on which
Family Ceramiaceae pedicellate tetrasporangia were produced.
Callithamniella tingitana** (Schousboe ex Accounts of this species have also been
Bornet) Feldmann-Mazoyer Figs 2c-e given by Schneider and Searles (1991) and
Type locality: Tangier, Morocco. by Dawes and Mathieson (2008) for material
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Additions to the marine flora of San Andrés
occurring on the coasts of North Carolina and (Mayhoub 1975). Our specimen can be
Florida, respectively. More recently, Secilla easily distinguished from D. nana by the
(2012) has described material of this species absence of unicellular rhizoids and from D.
from the coast of Spain. In the specimens neapolitana by the absence of secretory cells
collected, the branches are simple or with (Mayhoub 1975). Due to its small size, it is
a pseudo-dichotomy in the second or third easily overlooked. For the continental coast of
cell from the base, do not exceed 500 μm Colombia, it has been previously reported for
and are composed of up to 20 cells, while National Natural Park Tayrona and the Darien
for Callithamniella flexilis Baardseth, the region (Díaz-Pulido and Díaz-Ruiz 2003).
thallus has simple branches, up to 1000 μm
and composed of up to 30 cells.
Family Dasyaceae
Halydictyon mirabile* Zanardini Figs. 3a-b.
Dohrniella antillarum* (W.R. Taylor)
Type locality: Adriatic Sea.
Feldmann-Mazoyer Figs 2f-h
Type locality: Baie Anglais, Aquin, Haiti.
Specimens observed: San Andrés Island:
Green Moon: 6/II/2013, depth 12 m.
Specimens observed: San Andrés Island:
12/VIII/2013, depth 12 m. These were
Green Moon: 2/IV/2012, depth 9 m,
vegetative specimens. Specimen collected
vegetative specimen.
at Green Moon, 12/VIII/2013, deposited at
COL (COL 602241).
Thallus delicate (2.5–3 mm high) attached
to the substrate by multicellular rhizoids
Thallus soft, forming turfs like a mesh.
(Fig. 2f). Main branch erect, uniseriate, with
Light-pink to pale-red branches. Uniseriate
basal cells up to 65 µm diameter, 130 µm
axes formed of cylindrical cells, branched,
long, tapering towards the apex (Fig. 2g).
with branches fusing to form a mesh. The
Cells in the middle part of the axis 34 µm in
branchlets are 170 µm in diameter, cells
diameter, 62 µm in length, and at the apex,
up to 700 µm in length (Fig. 3a). The main
25–30 µm in diameter, 30 µm in length.
axis is indistinct. At the apex, cells are
The main axis bears alternately decumbent
rounded to semi-acute (Fig. 3b). Growing on
branchlets, which are 500 to 600 µm long
Canistrocarpus cervicornis and Halimeda
and have 1-2 elliptical papilliform cells
tuna (J. Ellis et Solander) J.V. Lamouroux,
(12 x 18 µm) located at distal cells of each
and attaching by small rhizoids.
branch (Fig. 2h). No reproductive structures
were observed. Specimens epiphytic on
Dictyota spp. Family Delesseriaceae
Frikkiella searlesii ** M.J. Wynne et C.W.
Remarks: the genus Dohrniella includes Schneider Figs. 3c-e.
only three species: D. neapolitana Funk, Type locality: Mona Island, Playa Carabinaro,
Dohrniella nana Mayhoub, which are Puerto Rico, Greater Antilles.
restricted to the Mediterranean basin, and
D. antillarum, described from Haiti, in the Specimens observed: San Andrés Island:
Caribbean Sea, and reported for the tropical Wild Life: Tetrasporic specimen, 4/IV/2013,
Western Atlantic and the Atlantic coast of depth 13 m; Spermatangial and tetrasporic
Africa (Guiry and Guiry c2017). These specimens, 09/VIII/2013, depth 14 m;
algae are characterized by their small size, Cystocarpic specimens, 4/IV/2013, depth 13
and the presence of papilliform cells, which m. Green Moon: Spermatangial specimen, 12/
is considered a characteristic of the genus VIII/2013, depth 12 m. Specimens collected
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a b c
d e f
Figure 3. Habit of species reported from the International Biosphere Reserve Seaflower. Halydictyon
mirabile: a. Filament branching in the center of thallus, b. Detail of filaments apex. Frikkiella
searlesii: c. Blade with central tetrasporangial sori, d. Blade bearing spermatangial sori, e. Blade
bearing a cystocarp. Taenioma nanum: f. Upper portion of blades with two monosiphonous “hairs” at
apex. Scale bar: a, c, d, e and f= 200 µm; b = 100 µm.
at Wild Life, 09/VIII/2013, deposited at COL Sea (Bahamas, Puerto Rico and Martinique).
(COL 602237 and COL 602240). It comprises two species: Frikkiella searlesii
and F. pseudoprostrata (D.L. Ballantine
Blades primarily monostromatic, 2–3 mm and M.J. Wynne) M.J. Wynne and C.W.
long and 1.5–2 mm wide. Cells of mature Schneider. They are easily distinguishable
blades have pentagonal or hexagonal shapes from one another by the arrangement of the
in surface view (Fig. 3c), the blade arising tetrasporangial sori. Our tetrasporangial
from a short rhizoidal holdfast, and also specimen fits well the description of F.
exhibiting marginal multicellular rhizoids searlesii. In the Caribbean Sea, this is the
in some portions of the blades. Third- southernmost record of the species.
order rows of cells produced only from
outer cells of second-order rows. Narrow Taenioma nanum* (Kützing) Papenfuss
tetrasporangial sorus in the center and distal Fig. 3f
region of the blade (Fig. 3c). Tetrasporangial Type locality: Naples, Italy.
tetrahedrally divided and to 70 µm diameter.
Spermatangial sori scattered over the surface Specimens observed: San Andrés Island:
of blades (Fig. 3d). Cystocarps on the mid- Wild Life: 22/I/2013, depth 17 m; 4/IV/2013,
line of 370–400 µm in diameter and 380– depth 13 m; 07/VI/2013, depth 14 m. Green
400 µm in length, with a ostiole measuring Moon: 6/II/2013, depth 12 m; 02/IV/2013,
up to 100 µm in diameter (Fig. 3e). depth 9 m; 12/VIII/2013, depth 12 m. All the
specimens were vegetative.
Remarks: The genus Frikkiella was described
by Wynne and Schneider (1996) based upon Thalli to 1 mm, creeping, observed growing
specimens from Bermuda and the Caribbean over larger algae such as Amphiroa tribulus
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Additions to the marine flora of San Andrés
(J. Ellis et Solander) J.V. Lamouroux, 17 m; Cystocarpic specimens, 04/IV/2013,
Canistocarpus cervicornis, Lobophora depth 13 m; Cystocarpic specimens, 7/VI/2013,
variegata, Halimeda spp., Sphacelaria sp., depth 14 m; Cystocarpic specimens, 09/
and the cyanophyte Phormidium sp. Often VIII/2013, depth 14 m. Green Moon: Tetrasporic
found as part of turf mats. Polysiphonous specimens, 7/XII/2012, depth 10 m; Vegetative
prostrate axes, with four pericentral cells; specimens and cystocarpic specimens, 6/
axes 60–80 µm in width, with uniseriate II/2013, depth 12 m; Vegetative, tetrasporic
rhizoids of 13–20 µm in width. The apices of and cystocarpic specimens, 2/IV/2013, depth 9
erect thalli have one apical cell or two apical m; Cystocarpic and vegetative specimens, 05/
hairs (Fig. 3f). No reproductive structures VI/2013, depth 10 m; Vegetative specimens and
were observed. cystocarpic specimens, 12/VIII/2013, depth 12
m. Cystocarpic specimen collected at Green
Remarks: To date, there are only two Moon, 02/IV/2013, deposited at COL (COL
recognized species of Taenioma: Taenioma 602236).
nanum and T. perpusillum (J. Agardh) J.
Agardh. The first species was described from Epiphytic and erect plant up to 3 cm high,
the Mediterranean Sea and has been reported found growing on Hypnea spinella (C.
in most oceans, thus with a cosmopolitan Agardh) Kützing, Dictyota spp., Coelothrix
distribution. In the Caribbean Sea, Taylor irregularis (Harvey) Børgesen, Halimeda
(1960) reported it as T. macrourum, which tuna and Riphocephalus phoenix f. longifolius
was later put in synonymy with T. nanum. A. Gepp et E. Gepp. Thalli with ecorticate
Taenioma perpusillum, the type species,
segments and four pericentral cells. Main
whose type locality is the Pacific coast of
axes 135–150 µm in diameter comprised of
Mexico, has a cosmopolitan distribution
segments 150–160 µm in length, fixed by
similar to the former taxon, including the
a basal disc with unicellular rhizoids 450
Caribbean Sea. The main characters to
µm length (Fig. 4a).Branchlets of 110 µm
differentiate the two species is the number
diameter and 120 µm length narrowed
of hairs at the apex of the erect axes, which
towards the apex. Scar cells occur one per
are one or two in T. nanum and three or
segment. Apex with hair-like filaments
more in T. perpusillum, and the number of
dichotomously divided. Apical and spherical
segments of erect determinate branches,
tetrasporangia spirally arranged up to 100 µm
which range from eight to 20 in T. nanum
in diameter (Fig. 4b). Spermatangial branches
and from 20 to 30 in T. perpusillum.
up to 100 µm width and 300 µm long, with
Despite that some authors in the past have
sterile cell at apex (Fig. 4c). Numerous
considered T. nanum and T. perpusillum to
dichotomically divided trichoblasts, up to 800
be conspecific (Hollenberg 1967, cited in
µm in length, of up to 10 cells in length, of 1–4
Womersley 2003), at present the two taxa
for each dichotomy. Cystocarps ovoid 250 µm
are recognized as separate. Our specimen
fits well the description of Taenioma nanum. in width, and 250 µm in length. Ostiole up to
130 µm long. Carpospores ovoid to 55–60 µm
Family Rhodomelaceae length and 25 µm with in the widest dimension
Melanothamnus gorgoniae** (Harvey) (Fig. 4d).
Díaz-Tapia et Maggs Figs 4a-d
Type locality: Key West, Florida, USA. Remarks: Melanothanmus gorgoniae was
originally described as Polysiphonia
Specimens observed: San Andrés Island: Wild gorgoniae (Harvey, 1853), with a type
Life: Cystocarpic, spermatangial, tetrasporic locality of Key West, Florida (USA). It
and vegetative specimens, 22/I/2013, depth was later transferred to Neosiphonia by
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Rincón-Díaz et al.
a b c d
Figure 4. Habit of species reported from the International Biosphere Reserve Seaflower.
Melanothamnus gorgoniae: a. Basal region of thallus on Dictyota sp., showing a disc of fixation
with rhizoids, b. Tetrasporangial branches, c. Spermatangial branchlets having sterile cell at apex
(arrowhead), and with many trichoblasts, d. Detail of cystocarp showing ostiole and carpospores.
Scale bar: a, b and c = 200 µm; d = 100 µm.
Guimarães and Fujii (in Guimarães et al. specimens, 2/XI/2012, depth 13 m. Tetrasporic
2004). Most recently, it was transferred to specimen collected at Wild Life, 02/XI/2012,
Melanothamnus by Díaz-Tapia and Maggs deposited at COL (COL 602239).
(in Díaz-Tapia et al. 2017), who provided
both molecular and morphological evidence Epiphytic plant, pinkish-red, spreading,
for their treatment. with prostrate axes attached to the substrate
This species is easily recognizable because by short unicellular rhizoids, with digitate
it is the only entirely erect species of ends, 20 µm long (Fig. 5a) placed distally
Polysiphonia-group in the area. Two in the cells of prostrate exes. Prostrate axes
other species of erect “Polysiphonia” are 20 µm in width, formed of rectangular cells
listed for the Caribbean Sea: Polysiphonia in surface view, to 100 µm long. Erect axes
binneyi Harvey and Melanothamus harveyi scattered unbranched, to 1.5 mm high,
Bailey Díaz-Tapia et Maggs. However, placed in the middle of prostrate cells, 15–
Polysiphonia binneyi differs from our 20 µm in width, cells to 55 µm long in the
species in that the branches arise in the basal portion of the axis. Erect axes slightly
axil of trichoblasts, while in M. gorgoniae tapering, apical cell 12.5 µm in diameter.
they replace the trichoblasts (Schneider and Tetrasporangia ovoid, 40–45 µm in diameter,
Searles 1991); M. harveyi is corticated at tetrahedrally divided, borne laterally on erect
the base, while our specimen is completely axes, or short lateral branches, 1–5 cells long
ecorticated. At this time, it is the only erect (Fig. 5b). Gametangia not observed.
species in this “Polysiphonia complex” for
the Archipiélago. Remarks: Díaz-Pulido and Bula-Meyer
(1997) reported Lejolisia mediterranea
Family Wrangeliaceae Bornet for the Archipelago of San Andres
Lejolisia exposita** C.W. Schneider et based on vegetative material. Although we
Searles Figs 5a, b lack cystocarpic material, the tetrasporangial
Type locality: Onslow Bay, North Carolina, specimens fit the description of L. exposita
USA. better than L. mediterranea. In his
description, Bornet (1859) reported that
Specimens observed: San Andrés Island: tetrasporangia are formed only on the basal
Wild Life: Tetrasporic and vegetative cell of the erect filaments for L. mediterranea
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Additions to the marine flora of San Andrés
a b
c d e
Figure 5. Habit of species reported from the International Biosphere Reserve Seaflower. Lejolisia
exposita: a. Habit with ovoid tetrasporangia, tetrahedrally divided, borne laterally or terminally on
erect axes, b. Detail of lateral tetrasporangia. Monosporus indicus: c. Detail of distal branchlets
portion, d. Prostrate axis and unicellular rhizoid, e. Oval one-celled propagules attached by triangular
pedicel (arrowhead). Scale bar: a and e = 100 µm; b = 50 µm; c and d = 200 µm.
and are borne on a one-cell pedicel (Bornet material (Díaz-Pulido and Díaz-Ruíz 2003),
1859, plate 1), while in L. exposita they we contend that the record of this species
are located in the basal and middle part of for Colombia is doubtful and propose to
the erect filament (Searles and Schneider eliminate it from the Colombian marine flora.
1989), borne terminally on 1–4 cell branches
(Searles and Schneider 1989, Figs 5a, b). Our Monosporus indicus** Børgesen Figs 5c-e
specimen has terminal tetrasporangia on 1–5 Type locality: Bombay, India.
celled branches, which may grow in the basal
through middle part of the erect filaments Specimens observed: San Andrés Island:
(Fig. 5b). Considering that a previous report Wild Life: Vegetative specimen; 4/IV/2013,
of L. mediterranea was based on vegetative depth 13 m; Vegetative specimen, 7/VI/2013,
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