Hamed A. El-Serehy

Beyond the “Code”: A Guide to the Description and Documentation of Biodiversity in Ciliated Protists (Alveolata, Ciliophora)

Recent advances in molecular technology have revolutionized research on all aspects of the biology of organisms, including ciliates, and created unprecedented opportunities for pursuing a more integrative approach to investigations of biodiversity. However, this goal is complicated by large gaps and inconsistencies that still exist in the foundation of basic information about biodiversity of ciliates. The present paper reviews issues relating to the taxonomy of ciliates and presents specific recommendations for best practice in the observation and documentation of their biodiversity. This effort stems from a workshop that explored ways to implement six Grand Challenges proposed by the International Research Coordination Network for Biodiversity of Ciliates (IRCN‐BC). As part of its commitment to strengthening the knowledge base that supports research on biodiversity of ciliates, the IRCN‐BC proposes to populate The Ciliate Guide, an online database, with biodiversity‐related data and metadata to create a resource that will facilitate accurate taxonomic identifications and promote sharing of data.

Systematic studies on ciliates (Alveolata, Ciliophora) in China: Progress and achievements based on molecular information

Due to complex morphological and convergent morphogenetic characters, the systematics of ciliates has long been ambiguous. Since 1990, the Laboratory of Protozoology, Ocean University of China, in collaboration with other research groups worldwide, has carried out a series of integrative investigations on ciliate systematics. To date, genomic DNA has been extracted from about 1700 ciliate strains, and phylogenetic analyses have been performed for two-thirds of orders. Main findings are: (1) Classifications of about 50 hypotrichous species have been resolved, although the monophylies of three hypotrichous orders remain unconfirmed; (2) Euplotia and two orders and all seven families within them are monophyletic assemblages; (3) Lynnella represents an order-level taxon, and is separated from two sister monophyletic subclasses Oligotrichia and Choreotrichia; (4) the peritrich families Zoothamniidae and Vorticellidae are separated from each other, and Zoothamnium exhibits a high genetic diversity; (5) the scuticociliate order Philasterida is monophyletic and separated from loxocephalids, and the thigmotrichids is a suborder within Pleuronematida; (6) 14 classes were recovered including one new class Protocruziea, and Mesodiniea is basal to subphyla Intramacronucleata and Postciliodesmatophora; (7) mitochondrial cytochrome c oxidase subunit I heteroplasmy was reported in ciliates for the first time, and candidate barcoding genes for Frontonia species identification were identified.

Diversity of free-living marine ciliates (Alveolata, Ciliophora): Faunal studies in coastal waters of China during the years 2011–2016

In the period 2011-2016, a series of investigations were carried out on the marine and brackish free-living ciliate fauna of the temperate-tropical coastal waters of China. About 210 morphotypes including over 100 new species within six groups (cyrtophorians, hypotrichs s.l., karyorelicteans, oligotrichs, pleurostomatids, and scuticociliates) were isolated and described in detail from observations of live cells and silver-stained specimens. Based on their morphology, morphogenesis and molecular phylogeny, three new families (Wilbertomorphidae, Kentrophyllidae, Protolitonotidae) and 22 new genera (Apotrachelocerca, Wilbertomorpha, Protolitonotus, Paracyrtophoron, Heterohartmannula, Aporthotrochilia, Falcicyclidium, Paramesanophrys, Pseudodiophrys, Monocoronella, Neourostylopsis, Apobakuella, Parabistichella, Heterokeronopsis, Heterotachysoma, Antiokeronopsis, Apoholosticha, Pseudogastrostyla, Antestrombidium, Sinistrostrombidium, Williophrya, and Varistrombidium) were established. In the present review, we summarize these studies which show there is a large, undiscovered diversity of ciliates, especially in undersampled habitats, such as subtropical/tropical coastal waters, mangrove wetlands, estuaries and aquaculture ponds. We also highlight the importance of integrative approaches, combining morphology, morphogenesis and molecular phylogeny, in order to understand ciliate systematics and ecosystem function.

Heavy metals contamination of a Mediterranean Coastal Ecosystem, Eastern Nile Delta, Egypt

The concentrations of Fe, Mn, Zn, Cu, Pb and Cd in bottom sediment and surface water in the Egyptian coastal waters along the Mediterranean Sea, and thence the soft tissues of the bivalve (Donax trunculus) were determined. The mean concentrations (µg g-1) of heavy metals in bottom sediment were as follows: Fe: 1748.2-2030, Mn: 191.4-254.3, Zn: 28-42.2, Cu: 4-9.4, Pb: 18.4-24.8, Cd: 1.4-2.3, and in surface water: Fe: 744-896, Mn: 162-198, Zn: 242.6-300, Cu: 12.6-19.3, Pb: 31.3-56, Cd: 0.8-3.1,while in soft tissues of the bivalve D. trunculus, the mean concentrations (µg g-1 dry weight) were as follows: Fe: 47.2-66.4, Mn: 4.8-8.4, Zn: 22-36.4, Cu: 3.2-4.8, Pb: 5.6-9.2, Cd: 1.6-2.4. The present study has revealed that the concentrations of Cd and Pb in the soft tissues of the edible bivalve D. trunculus were above the maximum acceptable concentrations for human consumption proposed by FAO/WHO, EU. Moreover, estimation of concentration factor (Cf) for the studied metals in the soft tissues of the edible bivalve D. trunculus recorded high accumulation rates of Cd and Cu. The present study confirmed that, the examined bivalve species was associated with enhanced metal content in its soft tissues and was not safe within the limits for human consumption. Water and bottom sediments showed apparent seasonal variations of metals accumulation with maximum concentrations during summer and winter, respectively. Mean metal concentrations were found to be higher in some of the selected five sites than others, but, these differences in heavy metal concentrations were not statistically significant (P>0.05), suggesting that common and main anthropogenic sources contributing to the heavy metal pollution at this Egyptian coastal area on the Mediterranean sea. The results obtained in this study were compared with those reported in earlier studies and concluded that, the area of the present study was in general not considered a metal polluted area according to the OME and EPA classification criteria. However, concentrations of Cd and especially, Pb did give some cause for concern, and warrants a continued monitoring programme for inorganic and chemical organic compounds in sediments, water, and biota along the Egyptian Mediterranean coasts.

Taxonomic Descriptions of Two Marine Ciliates, Euplotes dammamensis n. sp. and Euplotes balteatus (Dujardin, 1841) Kahl, 1932 (Ciliophora, Spirotrichea, Euplotida), Collected from the Arabian Gulf, Saudi Arabia

The morphology, morphogenesis and infraciliature of two marine euplotid ciliates, Euplotes dammamensis n. sp. and Euplotes balteatus (Dujardin, 1841) Kahl, 1932, isolated from a sandy beach of the Arabian Gulf, Saudi Arabia, were investigated using observa- tions in vivo and protargol-impregnation methods. Euplotes dammamensis n. sp. is characterized by a combination of features including its huge body size (100-170 × 80-120 μm), 10 conspicuous dorsal ridges, 10 normal-sized frontoventral and two marginal cirri, and 11 dorsal kineties. Euplotes balteatus is mainly characterized by 10 frontoventral, two caudal, and two left marginal cirri, 7-10 dorsal kineties and 5-7 prominent dorsal ridges as well as double-eurystomus silverline system. The small subunit rRNA (SSU-rRNA) gene sequences were determined for both species and phylogenetic analyses based on these data indicated that E. dammamensis is most closely related to E. parabalteatus Jiang et al., 2010, and E. balteatus clusters with E. plicatum Valbonesi et al., 1997, E. orientalis Jiang et al., 2010, and E. bisulcatus Kahl, 1932.

Evolutionary origins of abnormally large shoot sodium accumulation in nonsaline environments within the Caryophyllales

Summary The prevalence of sodium (Na)‐‘hyperaccumulator’ species, which exhibit abnormally large shoot sodium concentrations ([Na]shoot) when grown in nonsaline environments, was investigated among angiosperms in general and within the Caryophyllales order in particular. Shoot Na concentrations were determined in 334 angiosperm species, representing 35 orders, grown hydroponically in a nonsaline solution. Many Caryophyllales species exhibited abnormally large [Na]shoot when grown hydroponically in a nonsaline solution. The bimodal distribution of the log‐normal [Na]shoot of species within the Caryophyllales suggested at least two distinct [Na]shoot phenotypes within this order. Mapping the trait of Na‐hyperaccumulation onto the phylogenetic relationships between Caryophyllales families, and between subfamilies within the Amaranthaceae, suggested that the trait evolved several times within this order: in an ancestor of the Aizoaceae, but not the Phytolaccaceae or Nyctaginaceae, in ancestors of several lineages formerly classified as Chenopodiaceae, but not in the Amaranthaceae sensu stricto, and in ancestors of species within the Cactaceae, Portulacaceae, Plumbaginaceae, Tamaricaceae and Polygonaceae. In conclusion, a disproportionate number of Caryophyllales species behave as Na‐hyperaccumulators, and multiple evolutionary origins of this trait can be identified within this order.

Reproductive strategy of the jellyfish Aurelia aurita (Cnidaria Scyphomedusae) in the Suez Canal and its migration between the Red Sea and Mediterranean

The life history of the common jellyfish A. aurita (Linnaeus) in the Suez Canal was investigated by monthly sampling over a 28 month period from September 2006 to December 2008. Young medusae of 2–3 cm diameter appeared during February/March. Growth was rapid. Some specimens of this cohort reached 16 cm and spawned by March/May and then decreased in size or died. Others reached a maximal size of 10 cm by September, after which spawning took place. A few mature individuals remained after spawning in the next year but decreased in size. Release of ephyrae seems to be induced by a lowering of ambient environmental temperature to below 16°C, with peak of release occurring in December–February. A drop in temperature may be the primary cue for strobilation in the Suez Canal. A. aurita seems to be an immigrant plankter to the Suez Canal, and much interest was focused on determining from which end of the canal these organisms were invading the opposite sea. However, the canal itself, along with its lakes, should also be considered as a substantial permanent habitat in its own right. The canal cannot be considered only as a funnel or corridor through which animals pass like ships from one sea to the other. A. aurita appears to enter the Suez Canal from the south via water currents; to do so it needs to be carried over a distance of 20 km along the canal from the Gulf of Suez into the Bitter Lakes, then pass across the Bitter Lakes before being carried a further 12 km along the canal into Lake Timsah. Transport of A. aurita southward along the canal from the Mediterranean is unlikely to take place during most seasons of the year because it would require transport against the dominant-water flow; it is possible only during a brief period (July–September) of reversed flow. Because the main part of the 80 km from the Red Sea is canalized, passive transport of A. aurita by water currents from the north could occur within a week during the brief period of reversed flow even at the low speed of 0.5 km hour−1. Moreover, conditions (barriers, obstacles and/or links) along the migratory route of the Suez Canal, in either direction, are likely to determine the success of passive transport of A. aurita.

An overview of wetlands of Saudi Arabia: Values, threats, and perspectives

The wetlands of Saudi Arabia are located in a water-stressed region that is highly vulnerable to climate and other global changes. Sebkhas, mudflats, mangroves, and wadis are the dominant wetlands in the arid regions of North Africa and the Arabian Peninsula. These unique wetlands are recognized as a sanctuary for biodiversity and for their economic services generated from mineral extraction, agriculture, and grazing. Despite their ecological values and societal services, the long-term permanence of Saudi Arabia’s wetlands faces strong challenges resulting from human activities associated with sustained population growth, habitat degradation, and coastal development. This paper consolidates a literature review of Saudi Arabia’s wetlands from local to global importance, highlights their biodiversity, and identifies threats and evolution of these vulnerable ecosystems in the arid Arabian Peninsula by focusing on the status of key freshwater taxa (Odonata, freshwater fishes, amphibians, and waterbirds) and documenting changes affecting important wetlands.

Microbial–meiofaunal interrelationships in coastal sediments of the Red Sea

Population density and biomass of bacteria and meiofauna were investigated seasonally in the sediments of the north-western bank of Red Sea. Samples of sediments were collected seasonally from three different stations to determine microphytobenthic biomass (chlorophyll a), protein, lipid, carbohydrate, and total organic matter concentrations. These investigations revealed that microbial components tended to increase their dominancy, whereas sensitive meiofauna were extremely reduced during the entire study period. Thus a very low density of the total meiofauna (with an annual average of 109 ± 26 ind./10 cm2) was recorded whilst the benthic microbial population densities exhibited higher values (ranging from 0.31 ± 0.02 × 108 to 43.67 ± 18.62 × 108/g dry sediment). These changes in the relative importance analysis of benthic microbial components versus meiofaunal ones seem to be based on the impact of organic matter accumulation on the function and structure of these benthic communities. Proteins, lipids and carbohydrates showed very low concentration values, and the organic matter mostly consisted of carbohydrates, reflecting lower nutritional values for benthic fauna in general and meiofauna in particular. The distribution of microbial and meiofaunal communities seems to be dependent on the quality of the organic matter rather than on its quantity. Total organic matter concentrations varied between 5.8 and 7.6 mg/g, with organic carbon accounting for only 32% of the total organic matter. Chlorophyll a attained very low values, fluctuating between 0.11 and 0.56 μg/g, indicating the oligotrophy of the studied area. The very low concentration of chlorophyll a in the Red Sea sediment suggests that the sedimentary organic matter, heterotrophic bacteria and/or protozoa constitute an alternative resource that is consumed by meiofauna when algae are less abundant. Protozoa, therefore, represent the “missing link in bacteria–meiofauna interaction in the Red Sea marine sediment ecosystem.

Reproductive biology of the Suez Canal spider crab Schizophrys aspera (H. Milne Edwards, 1834: Crustacea: Brachyura: Majidae)

A reproductive biology study of the spider crab Schizophrys aspera (H. Milne Edwards, 1834) was conducted in the Suez Canal from July 2012 to June 2013. The annual sex ratio (Male:Female) of S. aspera was female biased with values of 1:1.25. Out of the four ovarian development stages of this crab, two stages were observed in the Suez Canal throughout the whole year. The ovigerous crab’s carapace width varied from 28 to 52 mm. This crab species can spawn during most of the year in the canal water, with a peak during late spring and early winter. The fecundity of ovigerous females ranged between 2349 and 13600 eggs with a mean of 5494 ± 1486 eggs. Female crabs that reached sexual maturity exhibited a minimum carapace width varying between 22 and 46 mm, and fifty percentage of all ovigerous females showed a carapace width of 36 mm.