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![Illustrations of Coscinodiscus spp. (A) Individuals in valve view of (1) Coscinodiscus concinnus, (2) C. granii (=C. concinnus) and (3, 4) C. cylindricus (=C. wailesii) from the same sample from the English Channel in 2018. (B) The same individuals in girdle view. Note that C. cylindricus (the mantle meets the valve face at right angle) can be smaller or larger than C. concinnus. The numbers marked each individual in valve and girdle views. (C and D) C. cylindricus from the English Channel in 2018. (E) Original description redrawn from Mangin [39]. Scale bar = 100 μm.](profile/Fernando-Gomez-36/publication/340142831/figure/fig5/AS:872952023244802@1585139389646/Illustrations-of-Coscinodiscus-spp-A-Individuals-in-valve-view-of-1-Coscinodiscus.png)
Illustrations of Coscinodiscus spp. (A) Individuals in valve view of (1) Coscinodiscus concinnus, (2) C. granii (=C. concinnus) and (3, 4) C. cylindricus (=C. wailesii) from the same sample from the English Channel in 2018. (B) The same individuals in girdle view. Note that C. cylindricus (the mantle meets the valve face at right angle) can be smaller or larger than C. concinnus. The numbers marked each individual in valve and girdle views. (C and D) C. cylindricus from the English Channel in 2018. (E) Original description redrawn from Mangin [39]. Scale bar = 100 μm.
Source publication
The translocation of species by human activities is a problem that increases with the globalization. However, the examples of non-indigenous or exotic planktonic microbes can be questioned as they predominantly have cosmopolitan distributions and natural mechanisms for wide dispersion. In reality, the categorization of any species as non-indigenous...
Contexts in source publication
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... currently accepted and the synonymy of the species can be complicated because the earlier descriptions were not very detailed or illustrations are missing [38]. The species of Coscinodiscus are coin-or drumshaped, and some species have a distinctive shape in girdle view, but they settle in settling chambers preferentially showing the valve view (Fig. 6A). Frustules fall in girdle view when there many cells in the sample (during blooms), if not we have rotated the cells (Fig. 6B). In girdle view, C. concinnus showed a distinctive convex dome-shaped valve or an asymmetric valve (wedge-shaped) in its morphotype C. granii (Fig. 6B), while cells with a rectangular outline were first ...
Context 2
... or illustrations are missing [38]. The species of Coscinodiscus are coin-or drumshaped, and some species have a distinctive shape in girdle view, but they settle in settling chambers preferentially showing the valve view (Fig. 6A). Frustules fall in girdle view when there many cells in the sample (during blooms), if not we have rotated the cells (Fig. 6B). In girdle view, C. concinnus showed a distinctive convex dome-shaped valve or an asymmetric valve (wedge-shaped) in its morphotype C. granii (Fig. 6B), while cells with a rectangular outline were first identified as C. nobilis and later as C. wailesii Fig.6. During decades in the North Atlantic, the taxonomists discussed about the ...
Context 3
... settle in settling chambers preferentially showing the valve view (Fig. 6A). Frustules fall in girdle view when there many cells in the sample (during blooms), if not we have rotated the cells (Fig. 6B). In girdle view, C. concinnus showed a distinctive convex dome-shaped valve or an asymmetric valve (wedge-shaped) in its morphotype C. granii (Fig. 6B), while cells with a rectangular outline were first identified as C. nobilis and later as C. wailesii Fig.6. During decades in the North Atlantic, the taxonomists discussed about the identity of C. concinnus and C. nobilis, while European researchers described that taxon in the Pacific Ocean as the new species C. cylindricus in 1928 ...
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... fall in girdle view when there many cells in the sample (during blooms), if not we have rotated the cells (Fig. 6B). In girdle view, C. concinnus showed a distinctive convex dome-shaped valve or an asymmetric valve (wedge-shaped) in its morphotype C. granii (Fig. 6B), while cells with a rectangular outline were first identified as C. nobilis and later as C. wailesii Fig.6. During decades in the North Atlantic, the taxonomists discussed about the identity of C. concinnus and C. nobilis, while European researchers described that taxon in the Pacific Ocean as the new species C. cylindricus in 1928 and C. wailesii in 1931 [39,40]. ...
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... low salinities [41]. Likely the salinity stress induces sexual reproduction and the maximum cell size is restored, hence the record of large cells under low salinity conditions. Consequently, under typical marine environmental conditions, C. cylindricus is small (250-300 μm) and easily confused with other congeneric species such as C. concinnus (Fig. 6A) or C. gigas. Blooms of a diatom that reaches a diameter of 500 μm require huge amounts of nutrients, including silica that would only be available under exceptional conditions. Estuaries are shallow environments with high nutrient availability, but high turbidity can reduce light availability and subsequent photosynthetic growth. ...
Context 6
... North Atlantic in the 1970's. In the past, that species was misidentified as C. nobilis or as large cells of C. concinnus. As Coscinodiscus cells settle in valve view, during the routine phytoplankton analysis, few cells are observed in girdle view, which shows the distinctive rectangular outline (the mantle meets the valve face at right angle, Fig. 6). Coscinodiscus cylindricus resembles C. nobilis, which was described with an almost flat valve face (Grunow, 1879). The presence of a hyaline central area in C. cylindricus is an unstable diagnostic character because the formation of a central rosette has been also reported (Schmid, 1990;Fernandes et al., ...
Context 7
... currently accepted and the synonymy of the species can be complicated because the earlier descriptions were not very detailed or illustrations are missing [38]. The species of Coscinodiscus are coin-or drumshaped, and some species have a distinctive shape in girdle view, but they settle in settling chambers preferentially showing the valve view (Fig. 6A). Frustules fall in girdle view when there many cells in the sample (during blooms), if not we have rotated the cells (Fig. 6B). In girdle view, C. concinnus showed a distinctive convex dome-shaped valve or an asymmetric valve (wedge-shaped) in its morphotype C. granii (Fig. 6B), while cells with a rectangular outline were first ...
Context 8
... or illustrations are missing [38]. The species of Coscinodiscus are coin-or drumshaped, and some species have a distinctive shape in girdle view, but they settle in settling chambers preferentially showing the valve view (Fig. 6A). Frustules fall in girdle view when there many cells in the sample (during blooms), if not we have rotated the cells (Fig. 6B). In girdle view, C. concinnus showed a distinctive convex dome-shaped valve or an asymmetric valve (wedge-shaped) in its morphotype C. granii (Fig. 6B), while cells with a rectangular outline were first identified as C. nobilis and later as C. wailesii Fig.6. During decades in the North Atlantic, the taxonomists discussed about the ...
Context 9
... settle in settling chambers preferentially showing the valve view (Fig. 6A). Frustules fall in girdle view when there many cells in the sample (during blooms), if not we have rotated the cells (Fig. 6B). In girdle view, C. concinnus showed a distinctive convex dome-shaped valve or an asymmetric valve (wedge-shaped) in its morphotype C. granii (Fig. 6B), while cells with a rectangular outline were first identified as C. nobilis and later as C. wailesii Fig.6. During decades in the North Atlantic, the taxonomists discussed about the identity of C. concinnus and C. nobilis, while European researchers described that taxon in the Pacific Ocean as the new species C. cylindricus in 1928 ...
Context 10
... fall in girdle view when there many cells in the sample (during blooms), if not we have rotated the cells (Fig. 6B). In girdle view, C. concinnus showed a distinctive convex dome-shaped valve or an asymmetric valve (wedge-shaped) in its morphotype C. granii (Fig. 6B), while cells with a rectangular outline were first identified as C. nobilis and later as C. wailesii Fig.6. During decades in the North Atlantic, the taxonomists discussed about the identity of C. concinnus and C. nobilis, while European researchers described that taxon in the Pacific Ocean as the new species C. cylindricus in 1928 and C. wailesii in 1931 [39,40]. ...
Context 11
... low salinities [41]. Likely the salinity stress induces sexual reproduction and the maximum cell size is restored, hence the record of large cells under low salinity conditions. Consequently, under typical marine environmental conditions, C. cylindricus is small (250-300 μm) and easily confused with other congeneric species such as C. concinnus (Fig. 6A) or C. gigas. Blooms of a diatom that reaches a diameter of 500 μm require huge amounts of nutrients, including silica that would only be available under exceptional conditions. Estuaries are shallow environments with high nutrient availability, but high turbidity can reduce light availability and subsequent photosynthetic growth. ...
Context 12
... North Atlantic in the 1970's. In the past, that species was misidentified as C. nobilis or as large cells of C. concinnus. As Coscinodiscus cells settle in valve view, during the routine phytoplankton analysis, few cells are observed in girdle view, which shows the distinctive rectangular outline (the mantle meets the valve face at right angle, Fig. 6). Coscinodiscus cylindricus resembles C. nobilis, which was described with an almost flat valve face (Grunow, 1879). The presence of a hyaline central area in C. cylindricus is an unstable diagnostic character because the formation of a central rosette has been also reported (Schmid, 1990;Fernandes et al., ...
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... Thus, local experts may not be able to decide if an unfamiliar species is introduced or native. For example, distinguishing native from introduced polychaetes (Kupriyanova et al. 2013) and unicellular plankton (Gómez 2008(Gómez , 2019Gómez et al. 2019) can be challenging. These challenges make comparisons among regions extremely difficult without a global perspective. ...
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A major historical challenge for the management of anthropogenic introductions of
species has been the absence of a globally standardised system for species
nomenclature. For over a decade, the World Register of Marine Species (WoRMS)
has provided a taxonomically authoritative classification and designation of the
currently accepted names for all known marine species. However, WoRMS mainly
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database directly linked to WoRMS that includes all introduced marine species,
distinguishing native and introduced geographic ranges. Both the WoRMS and
WRiMS contents are continually updated by specialists who add citations of
original species descriptions, key taxonomic literature, images and notes on native
and introduced geographic distributions. WRiMS editors take responsibility for
assessing the validity of species records by critically evaluating if a species has
been introduced to a region, erroneously identified and/or potentially naturally
present in a region but previously unnoticed. WRiMS currently contains 2,714
introduced species. The amount and quality of the information entered depend on
the availability of experts to update its contents. Because WRiMS is global and it
combines species taxonomic and geographic information with links to other
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Marampouti et al. (2021) offer a “final list of introduced harmful
algal species” encompassing fifteen species of dinoflagellates,
four diatoms, and one raphidophyte. The authors list the “origin”
(Supplementary Material), presumably the natural range of the
species, according to their definition of invasive alien species.
Incongruently, the authors chose to illustrate the process of the
“tropicalization” of the Mediterranean Sea using Alexandrium
ostenfeldii introduced from subarctic waters; A. andersonii from
Cape Cod, USA; Lingulodinium polyedra from the Baltic Sea;
Coolia monotis from the North Sea; and Dinophysis acuminata
from a Norwegian fjord. In the early 1990s,
Alexandrium andersonii and Gessnerium (=Alexandrium)
taylorii were described from the historically important marine
farming regions of Cape Cod and Arcachon, respectively. Yet,
until the late 1990s, they were pooled as Gonyaulax
tamarensis or G. catenella in the Mediterranean Sea due to
taxonomic difficulties, though Gessnerium taylorii is more
common in the Mediterranean Sea than in its type locality.
Epiphytic dinoflagellates (Coolia, Gambierdicus, Ostreopsis,
Prorocentrum, Sinophysis) have received full scientific attention
in the late 1970s, once some warm water species were
identified as associated with Ciguatera fish poisoning. As in
the case of Alexandrium, the first monitoring surveys in the
Mediterranean Sea began when many of the epiphytic dinoflagellate
species were already described fromother regions. It
is entirely possible that species categorized as alien are native
biota. Intense research effort following a toxigenic event in
late 1980s, attributed to the domoic acid produced by species
of the diatom genus Pseudo-nitzschia, resulted in the description
of numerous new taxa. Again, when the first detailed
studies on the diversity of Pseudo-nitzschia began in the
Mediterranean Sea, species already described in other locations
were identified (i.e., P. multistriata in Japan) and categorized
as aliens. The use of molecular tools in aiding robust identification has
revealed that Mediterranean populations are genetically distinct
from their supposed natural populations (see details in the
Appendix S1 as Supplementary Material): Alexandrium
ostenfeldii, Protogonyaulax catenella (=Alexandrium pacificum)
or Ostreopsis ovata Mediterranean populations are genetically distinct from individuals in the subarctic Seas or the Pacific
Ocean, respectively. The Mediterranean Sea and Atlantic populations
of Coolia monotis, Alexandrium ostenfeldii, or
Gessnerium taylorii are contiguous, and no evidence is provided
for being introduced outside of their natural range or natural
dispersal potential. Prorocentrum shikokuense Y.Hada 1975 is
listed as an alien originating from East China, Korea, and Japan,
when in fact it is a junior synonym of P. obtusidens J.Schiller
1928, first described from the Adriatic Sea, and Sinophysis
canaliculata is characterized as harmful though no evidence is
provided in support. The authors should have provided references
to the original publications on which their data is based
rather than second- and third-hand compilations that do not allow
to track the original source for each taxon (i.e., Karenia
mikimotoi). Marampouti et al. (2021, Appendix S1 as
Supplementary Material) listed Chaetoceros bacteriastroides
and C. pseudosymmetricus as alien and harmful species in the
eutrophic Adriatic Sea introduced by “Levantine inflow currents”.
These species are not aliens because they are considered
synonyms of the cosmopolitan species C. pseudocurvisetus and
C. affinis that are common in the Mediterranean Sea. These distinct from individuals in the subarctic Seas or the Pacific
Ocean, respectively. The Mediterranean Sea and Atlantic populations
of Coolia monotis, Alexandrium ostenfeldii, or
Gessnerium taylorii are contiguous, and no evidence is provided
for being introduced outside of their natural range or natural
dispersal potential. Prorocentrum shikokuense Y.Hada 1975 is
listed as an alien originating from East China, Korea, and Japan,
when in fact it is a junior synonym of P. obtusidens J.Schiller
1928, first described from the Adriatic Sea, and Sinophysis
canaliculata is characterized as harmful though no evidence is
provided in support. The authors should have provided references
to the original publications on which their data is based
rather than second- and third-hand compilations that do not allow
to track the original source for each taxon (i.e., Karenia
mikimotoi). Marampouti et al. (2021, Appendix S1 as
Supplementary Material) listed Chaetoceros bacteriastroides
and C. pseudosymmetricus as alien and harmful species in the
eutrophic Adriatic Sea introduced by “Levantine inflow currents”.
These species are not aliens because they are considered
synonyms of the cosmopolitan species C. pseudocurvisetus and
C. affinis that are common in the Mediterranean Sea. These species belong to the subgenus Hyalochaeta, with thinner setae,
which are not associated with harmful effects. The “final list of introduced harmful algal species” by Marampouti et al. (2021) contains species that are not harmful, and no species is an indisputably validated introduction (see details in the Appendix S1 as Supplementary Material).
