New scenario for speciation in the benthic dinoflagellate genus Coolia (Dinophyceae)

In this study, inter- and intraspecific genetic diversity within the marine harmful dinoflagellate genus Coolia Meunier was evaluated using isolates obtained from the tropics to subtropics in both Pacific and Atlantic Ocean basins. The aim was to assess the phylogeographic history of the genus and to clarify the validity of established species including Coolia malayensis. Phylogenetic analysis of the D1-D2 LSU rDNA sequences identified six major lineages (L1–L6) corresponding to the morphospecies Coolia malayensis (L1), C. monotis (L2), C. santacroce (L3), C. palmyrensis (L4), C. tropicalis (L5), and C. canariensis (L6). A median joining network (MJN) of C. malayensis ITS2 rDNA sequences revealed a total of 16 haplotypes; however, no spatial genetic differentiation among populations was observed. These MJN results in conjunction with CBC analysis, rDNA phylogenies and geographical distribution analyses confirm C. malayensis as a distinct species which is globally distributed in the tropical to warm-temperate regions. A molecular clock analysis using ITS2 rDNA revealed the evolutionary history of Coolia dated back to the Mesozoic, and supports the hypothesis that historical vicariant events in the early Cenozoic drove the allopatric differentiation of C. malayensis and C. monotis.     

Morphological and genetic analysis of the Coolia monotis species complex with the introduction of two new species,Coolia santacroce sp. nov. and Coolia palmyrensis sp. nov. (Dinophyceae)

The dinoflagellate genus Coolia Meunier is an important epi-benthic organism that is commonly found in association with other dinoflagellates known to cause ciguatera. Two closely related taxa, Coolia monotis and Coolia malayensis, make up the C. monotis species complex. In this study we introduce two new toxic species that should be included in that complex, Coolia palmyrensis Karafas, Tomas, York sp. nov. and Coolia santacroce Karafas, Tomas, York sp. nov., collected from the Palmyra Atoll in the Pacific Ocean and Saint Croix, US Virgin Islands, respectively. These two species can be distinguished morphologically by size, pore shape, pore density, and the relative size of the apical pore complex. The ITS1/5.8S/ITS2 and the D1/D2 regions of the LSU rDNA were used to provide molecular support of morphological observations using maximum likelihood and Bayesian analyses. Furthermore, C. palmyrensis and C. santacroce both showed cytotoxic effects on human derived cells in vitro.     

First report of the epiphytic benthic dinoflagellates Coolia canariensis and Coolia malayensis in the waters off Jeju Island, Korea: morphology and rDNA sequences

Coolia spp. are epiphytic and benthic dinoflagellates. Herein, we report for the first time, the occurrence of Coolia canariensis and Coolia malayensis in Korean waters. The morphology of the Korean strains of C. canariensis and C. malayensis isolated from the waters off Jeju Island, Korea was similar to that of the original Canary lslands strains and Malaysian strains, respectively. We found several pores and a line of small knobs on the pore plate, and perforations within the large pores of both C. canariensis and C. malayensis. The plates of the Korean strains of C. canariensis and C. malayensis were arranged in a Kofoidian series of Po, 3′, 7′′, 6c, 6s, 5′′′, and 2′′′′, and Po, 3′, 7′′, 7c, 6–7s, 5′′′, and 2′′′′, respectively. When properly aligned, the large subunit (LSU) rDNA sequence of the Korean strain of C. canariensis was identical to that of the Biscayan strains, but it was 2–3% different from the Canary lslands strain VGO0775 and the Australian strain. In addition, the sequences of small subunit (SSU) and/or LSU rDNA from the two Korean strains of C. malayensis were < 1% different from the Malaysian strains of C. malayensis and the Florida strain CCMP1345 and New Zealand strain CAWD39 (“Coolia monotis”). In phylogenetic trees based on LSU rDNA sequences, the Korean strains of C. malayensis belonged to a clade including the Malaysian strains and these two strains. Therefore, based on genealogical analyses, we suggest that the Korean strain of C. canariensis is closely related to two Atlantic strains and the Australian strain, whereas the Korean strains of C. malayensis are related to the Malaysian strains of C. malayensis and the Florida and New Zealand strains.     

First report of epiphytic dinoflagellate Coolia malayensis (Dinophyceae) in the southeastern Pacific Ocean

Coolia species are epiphytic and benthic dinoflagellates with a cosmopolitan distribution in tropical and subtropical areas. In the austral summer of 2016, during a survey in Bahía Calderilla, a dinoflagellate of the genus Coolia was detected in macroalgae samples, and a clonal culture was established. Subsequently, the cultured cells were observed by scanning electron microscopy (SEM) and identified as C. malayensis based on their morphological characteristics. Phylogenetic analyses based on the LSU rDNA D1/D2 regions confirmed that strain D005-1 corresponded to C. malayensis and clustered with strains isolated from New Zealand, Mexico, and Asia Pacific countries. Although the strain D005-1 culture did not contain yessotoxin (YTX), cooliatoxin, 44-methyl gambierone, or its analogs in detectable amounts by LC–MS/MS, more research is needed to evaluate its toxicity and to determine the possible impact of C. malayensis in northern Chilean waters.     

<Emphasis Type="Italic">Membraniporopsis tubigera</Emphasis>, an invasive bryozoan in sandy beaches of southern Brazil and Uruguay

The massive irruption of the invasive bryozoan Membraniporopsis tubigera (Osburn) in sandy beaches of southern Brazil and Uruguay is reported. The species, originally described from Puerto Rico, Texas and Florida, has also been recorded for Brazilian beaches from 21°S to 26°S as well as for harbours of Australia, New Zealand and the Sea of Japan. The southward spreading rate of this bryozoan along the Brazilian and Uruguayan coasts can be estimated in approximately 183–195 km year⁻¹. The chances that this invasion could proceed southwards in the Southwest Atlantic and the possible impacts that it may be causing are discussed. The case of M. tubigera seems to be qualitatively and quantitatively different from those of other alien bryozoans previously recorded for this region, since it appeared massively in exposed sandy beaches, a habitat regarded to date as apparently free from the pervasive ecological impact of invasion by exotic species in the Southwest Atlantic.     

COOLIA CANARIENSIS SP. NOV. (DINOPHYCEAE), A NEW NONTOXIC EPIPHYTIC BENTHIC DINOFLAGELLATE FROM THE CANARY ISLANDS1

A new photosynthetic dinoflagellate species, Coolia canariensis S. Fraga sp. nov., is described based on samples taken from tidal ponds on the rocky shore of the Canary Islands, northeast Atlantic Ocean. Its morphology was studied by LM and SEM. It is almost spherical and has a thick smooth theca with many scattered pores. Plate 1′ is the biggest of the epithecal plates, and 7″ is twice as wide as it is long. Phylogeny inferred from the D1/D2 regions of the LSU nuclear rDNA of three strains of C. canariensis and several strains of other Coolia species, C. monotis, C. sp., showed that C. canariensis strains clustered in a well‐supported clade distinct from the other species. No toxins were detected using mouse bioassay, liquid chromatography with Fluorescence detection (LC‐FLD) or liquid chromatography‐mass spectrometry (LC‐MS). Its pigment composition is of the peridinin type of dinoflagellates. Together with this new species, many other strains of C. monotis from the Atlantic Ocean and Mediterranean Sea have been analyzed for toxin presence, and no evidence of toxin production related to yessotoxins (YTXs) was found, as was previously suggested for C. monotis from Australia.     

CHARACTERIZATION OF OSTREOPSIS AND COOLIA (DINOPHYCEAE) ISOLATES IN THE WESTERN MEDITERRANEAN SEA BASED ON MORPHOLOGY,TOXICITY AND INTERNAL TRANSCRIBED SPACER 5.8S rDNA SEQUENCES1

Several isolates of epiphytic dinoflagellates belonging to the genera Ostreopsis Schmidt and Coolia Meunier from the western Mediterranean Sea were examined by LM and EM, toxicity assays, and internal transcribed spacer (ITS) regions of nuclear rDNA, and 5.8S rDNA were sequenced. Morphological comparisons based on the analyses of cell shape, size, thecal plates, and surface ornamentation revealed two distinct species in the western Mediterranean: O. cf. siamensis Schmidt from the Catalan, Andalusian, and Sicilian coasts and O. ovata Fukuyo from the Ligurian coast, southern Tyrrhenian Sea, and Balearic Islands. Both Ostreopsis species were toxic; however, no differences in toxicity were detected between the two Ostreopsis species. Coolia monotis Meunier was nontoxic. The morphological studies were supported by phylogenetic analyses; all western Mediterranean isolates of O. cf. siamensis showed ITS and 5.8S rDNA sequences identical to each other and so did those of O. ovata, whereas high genetic diversity was detected between the western Mediterranean and Asian isolates of O. ovata. The nucleotide sequence analyses of the C. monotis strains showed that all C. monotis isolates from Europe formed a homogeneous clade. Further, the genetic diversity was high between the European and Asian C. monotis isolates. In this study, genetic markers combined with morphology and toxicity analyses was useful in the taxonomic and phylogenetic studies of the Ostreopsidaceae in a temperate area.     

Phylogenetic relationships in the harmful dinoflagellate Cochlodinium polykrikoides (Gymnodiniales, Dinophyceae) inferred from LSU rDNA sequences

Phylogenetic relationships among chain-forming Cochlodinium species, including the harmful red tide forming dinoflagellate Cochlodinium polykrikoides, were investigated using specimens collected from coastal waters of Canada, Hong Kong, Japan, Korea, Malaysia, México, Philippines, Puerto Rico, and USA. The phylogenetic tree inferred from partial (D1–D6 regions) large subunit ribosomal RNA gene (LSU rDNA) sequences clearly differentiated between C. polykrikoides and a recently described species, Cochlodinium fulvescens. Two samples collected from the Pacific coasts of North America (British Columbia, Canada and California, USA) having typical morphological characters of C. fulvescens such as the sulcus located in the intermediate region of the cingulum, were closely related to C. fulvescens from western Japan in the phylogenetic tree. Cochlodinium polykrikoides formed a monophyletic group positioned as a sister group of the C. fulvescens clade with three well-supported sub-clades. These three clades were composed of (1) East Asian, including specimens collected from Hong Kong, western Japan, and southern Korea, (2) Philippines, from Manila Bay, Philippines and Omura Bay, Japan, and (3) American/Malaysian, from the Atlantic coasts of USA, the Pacific coast of México, Puerto Rico, and Borneo Island, Malaysia. Each of these clades is considered to be a so-called “ribotype” representing the population inhabiting each region, which is distinguished based on ribosomal RNA gene sequences in the species despite similarities in their morphological characters.     

Athecate hydroids from Puerto Rico and the virgin Islands

About 31 athecate hydroids collected from Puerto Rico and the vicinity are recorded, 9 for the first time in the Caribbean Sea. Two new genera, Heterocoryne and Millardiana, and four new species, Heterocoryne caribbensis, Millardiana longitentaculata, Silhouetta puertoricensis and Stylactis sandrae, are described.     

Sea level,topography and island diversity: phylogeography of the Puerto Rican Red‐eyed Coquí, Eleutherodactylus antillensis

Quaternary climatic oscillations caused changes in sea level that altered the size, number and degree of isolation of islands, particularly in land‐bridge archipelagoes. Elucidating the demographic effects of these oscillations increases our understanding of the role of climate change in shaping evolutionary processes in archipelagoes. The Puerto Rican Bank (PRB) (Puerto Rico and the Eastern Islands, which comprise Vieques, Culebra, the Virgin Islands and associated islets) in the eastern Caribbean Sea periodically coalesced during glaciations and fragmented during interglacial periods of the quaternary. To explore population‐level consequences of sea level changes, we studied the phylogeography of the frog Eleutherodactylus antillensis across the archipelago. We tested hypotheses encompassing vicariance and dispersal narratives by sequencing mtDNA (c. 552 bp) of 285 individuals from 58 localities, and four nuDNA introns (totalling c. 1633 bp) from 173 of these individuals. We found low support for a hypothesis of divergence of the Eastern Islands populations prior to the start of the penultimate interglacial c. 250 kya, and higher support for a hypothesis of colonization of the Eastern Islands from sources in eastern Puerto Rico during the penultimate and last glacial period, when a land bridge united the PRB. The Río Grande de Loíza Basin in eastern Puerto Rico delineates a phylogeographic break. Haplotypes shared between the PRB and St. Croix (an island c. 105 km south‐east of this archipelago) likely represent human‐mediated introductions. Our findings illustrate how varying degrees of connectivity and isolation influence the evolution of tropical island organisms.     

DUDRESNAYA PUERTORICENSIS SP. NOV. (DUMONTIACEAE,GIGARTINALES, RHODOPHYTA)1

A new species of Dudresnaya is described from Puerto Rico and Georgia. Gametophytes have cylindrical axes, exserted apical cells, rectangular to hexagonal crystals in the axial cells, ellipsoidal outer assimilatory cells, spermatangial mother cells which are terminal or subterminal cells of the subdichotomously branched outer assimilatory branches and auxiliary cells which are indistinguishable in appearance from adjacent, large, deeply staining cells of the auxiliary cell branch. Tetrasporophytes are unknown.     

Phylogenetics,delimitation and historical biogeography of the pantropical tree genus Thespesia (Malvaceae,Gossypieae)

Thespesia consists of 16 species of trees and shrubs from Southeast Asia–Oceania, Africa and America, the most well known being T. populnea, a small tree of tropical coastal areas around the world. Phylogenetic relationships in the genus and among its allies in tribe Gossypieae were inferred using three plastid and two nuclear regions to ascertain its generic delimitation and explore its biogeographical history. Maximum‐likelihood and Bayesian analyses confirmed that Thespesia is not monophyletic and, based on these results, Azanza is reinstated to accommodate the two species previously placed in Thespesia section Lampas. Dating analyses and ancestral range estimation indicated that Thespesia s.s. most likely originated in Southeast Asia–Oceania c. 30 Mya, but extant species did not begin to differentiate until the late Miocene. Two dispersal events, one into Africa c. 11 Mya and another into America (Antilles) c. 9 Mya, gave rise to the African and the Greater Antillean endemics, respectively. The two most widespread hydrochorous species, T. populnea and T. populneoides, originated in Southeast Asia–Oceania from where they spread to other parts of the world. Our analysis also indicated a much earlier origin than previously reported for the eumalvoid clade and its tribes Gossypieae, Malveae and Hibisceae suggesting that vicariance might have had an important role early in the history of these groups.     

A new species of Lepanthes (Orchidaceae) from Puerto Rico

A new species,Lepanthes caritensis, is described and illustrated. There are now nine species ofLepanthes known to occur in Puerto Rico. Plant habitat and floral morphology ofL. caritensis is most similar to that ofL. sanguinea. A survey of the area where the new species is located suggests that it is rare and should be protected under the Federal Endangered Species Act. Una especic nueva,Lepanthes caritensis, es descrita e ilustrada para Puerto Rico. Con ésta hay ahora nueve especies deLepanthes en Puerto Rico. El hábito de la planta y la morfología de la flor deL. caritensis es más similar aL. sanguinea. Un muestreo del área donde se encuentra la nueva especie sugiere que ésta es rara y que debería ser protegida por el Federal Endangered Species Act.     

Regeneration filters in post-agricultural fields of Puerto Rico and Ecuador

To better understand how rainforest regenerates after agriculture I sampled the seed rain and seed bank, and set out seeds and seedlings, on microsites defined by distance to the forest in fields both in Puerto Rico and Ecuador. I found that (1) total seeds, species richness and life-form richness were twice as great in the Ecuador seed rain compared to Puerto Rico but Puerto Rico seeds were more evenly distributed among species and (2) total seedlings from the seed bank were similar between Puerto Rico and Ecuador, (3) the majority of seeds were lost to predation among all species and study sites, (4) seed disease was absent in P. aduncum and Miconia prasina, and no seeds germinated for Gonzalagunia spicata and P. riparia, (5) in Ecuador pathogenic disease claimed more seeds than germinated for all species, and Solanum ovalifolium was the only species that had seeds germinate but did not lose seeds to disease, (6) also in Ecuador, insect predation was significantly lower in the forest border for P. aduncum, and seed disease was significantly greater at the 10 m micro site for S. ovalifolium, (7) distance has a significant effect on seedling height and basal diameter, (8) losses of leaf area due to herbivory and pathogens were always low and (9) biomass and leaf specific mass were significantly reduced in the border and forest microsites. I conclude that Ecuador fields had more seeds, species, and life-forms than Puerto Rico fields, predation was the most severe post-dispersal seed filter in all fields, seeds that survived predation on Puerto Rico were lost either to disease or germination but to both mechanisms in Ecuador, all three seed mechanisms in Ecuador fields showed distance effects of seedling growth but not survivorship.     

Cellular fatty acid composition ofCorallococcus coralloides

The fatty acid composition of five strains ofCorallococcus coralloides and three reference species ofMyxococcus were determined by gas-liquid chromatography. Methyl esters of fatty acid containing from 12 to 22 carbon atoms were identified. The major fatty acids present were C₁₅ and C₁₇ saturated branched chain, and both C₁₆ saturated and unsaturated straight chain acids. The C₁₇ saturated branched and straight chain acids, which were in valuable concentration in species ofMyxococcus, were not, however, detected in all strains ofC. coralloides. The application of these results in the distinction ofC. coralloides from the genusMyxococcus is discussed.     

Response to carbon monoxide by geographic variants in Acacia farnesiana

Differences in degree of defoliation in CO-air mixtures were shown by geographic variants in Acacia farnesiana (L.) Willd., a widespread, weedy, pantropic, leguminous tree. Laboratory-germinated seedlings from Mazatlán (MAME-1), Sinaloa, Mexico, showed greater sensitivity to a CO gradient than plants from Point Tuna (PORO), Puerto Rico. Seedlings of both strains grown under a light intensity of 200 ft-c showed greater sensitivity to CO than those grown under 1,800 ft-c. When intact plants of 17 geographic variants grown at low-light intensities were exposed to 2% CO in air, 11 strains (Mexico, 8; Texas, 1; California, 1; Guatemala, 1) showed almost complete defoliation. The other six strains—from Brazil, Hawaii, Puerto Rico, Italy, Algeria, and Micho-acán, Mexico—showed defoliation averaging from 23 to 70%. The significance of the CO-de-foliation response is difficult to explain in terms of the natural distribution of A. farnesiana. It is suggested that this response may be correlated with some biochemical process of adaptive significance.     

Effect of harvesting, vegetation structure and composition on the abundance and demography of the land crab Cardisoma guanhumi in Puerto Rico

Cardisoma guanhumi is the focus of an important artisanal fishery in Puerto Rico. Data on land crab landings point towards a dramatic decline in their abundance. This is cause for concern given the intrinsic value of the fishery and the important role these crabs play in coastal ecosystems. In this paper we examine the effect of harvesting and habitat quality on the abundance, survival, and size structure of C. guanhumi. To accomplish this we conducted a capture-mark-recapture study for a period of 18 months at three localities with minimal or no harvesting, and three with intense harvesting. Habitat quality at the six study sites was assessed by measuring vegetation composition-structure and litter biomass. We also conducted a leaf consumption experiment to evaluate leaf litter selectivity and limitation. Mean crab abundance differed significantly among sites, and this variation was significantly explained by differences in crab survival among sites. Sites with less harvesting tended to have higher survivorship and more crabs than sites where harvesting took place. Crabs mean size differed among study sites and was inversely related to abundance. Vegetation composition and structure, leaf litter standing stock and leaf-litter consumption differed among study sites. However, only some of these habitat characteristics are directly related to crab abundance or demography. There is a tendency for sites with a high leaf litter standing stock and large basal area to have the largest crabs but in low abundance. This study shows that C. guanhumi populations are very sensitive to increases in mortality that result from harvesting, and that the historical decline in abundance of this crab in Puerto Rico can be explained, in part, by an increase in trapping effort. Our results also indicate that C. guanhumi is a very plastic species, capable of occupying diverse types of coastal forests and a leaf litter generalist.