Cladocera from the Sudan: Red Sea Hills,Jebel Marra and valley of the main Nile

Twenty species of Cladocera are reported from the Nile, where lacustrine species dominate, and from Jebel Marra and the Red Sea Hills, where chydorids dominate. The community found in the Red Sea Hills is more typically desertic than that of Jebel Marra, which appears closely related to the fauna of the West and Central African Sahel.     

A review of the rotifer fauna of the Sudan

A collection of rotifers contained in samples from the Blue, White and joint Niles in the Sudan, the Red Sea Hills, and Jebel Marra mountains is studied, and the previous literature on the rotifera of Sudan is reviewed. A total of 145 rotifer taxa are now known from this country. Ecological and distributional notes on selected species are added. Besides cosmopolitan, pantropical, and tropical species, a small but significant fraction of the fauna is of northern origin, possibly reflecting climatic conditions of the late-Pleistocene.     

rDNA analysis of the Red Sea seagrass,Halophila, reveals vicariant evolutionary diversification

The effects of opening the Suez Canal as a connection between the Red Sea and the Mediterranean Sea were reported for a number of marine species. However, the evolutionary origin of the seagrasses in the Red Sea and the linking population genetics of seagrasses between the Arabian Sea, the Gulf of Aden, the Red Sea and the Mediterranean Sea have not yet been investigated in detail. The invasion of Halophila stipulacea Asch. from the Red Sea into the Mediterranean Sea after the opening of the Suez Canal was already recorded. We hypothesize that Halophila ovalis populations in the Red Sea developed through long-term historical processes such as vicariant evolutionary diversification. Seagrass samples were collected along the Egyptian coastline of the Red Sea and analysed by the molecular marker ITS. The sequences were compared with published ITS sequences from seagrasses collected in the whole area of interest. In this study, we reveal the linking population genetics, phylogeography and phylogenetics of two dominant seagrass species, Halophila stipulacea and Halophila ovalis, among species collected in the Red Sea and worldwide. The results indicate that the Red Sea Halophila ovalis populations do not group to Halophila ovalis worldwide, and Halophila major, Halophila ovalis collected worldwide and Halophila ovalis collected at the Red Sea are sister clades. Hence, vicariant evolutionary diversification for Halophila ovalis may occur in the Red Sea.     

Molecular analysis of the recently described lizardfish Saurida lessepsianus (Synodontidae) from the Red Sea and the Mediterranean,with remarks on its phylogeny and genetic bottleneck effect

The opening of the Suez Canal in 1869 led to a massive influx of Red Sea species that invaded the Mediterranean; this was termed ‘Lessepsian migration'. Among these species was a species of lizardfish, identified by some authors as Saurida undosquamis and by others as S. macrolepis. Recently, the Red Sea and the Mediterranean populations were described according to external characteristics as a unique taxon, Saurida lessepsianus. Our molecular study confirms this finding and determines that all previous records of S. undosquamis and S. macrolepis in the Red Sea and the Mediterranean are misidentifications of S. lessepsianus. The Mediterranean population of S. lessepsianus exhibits a lower genetic variability than that of the Red Sea population, suggesting a bottleneck effect.     

The microcopepod fauna in the Eastern Mediterranean and Arabian Seas: a comparison with the Red Sea fauna

Multiple opening-closing nets of 0.05 mm mesh size were employed to study the community structure and vertical distribution of microcopepods at selected stations in the Red Sea, Arabian Sea and Eastern Mediterranean Sea down to a maximum depth of 1850 m. Calanoids, cyclopoids (Oithona and Paroithona) and poecilostomatoids (mainly Oncaea) were the 3 most abundant orders. In the epipelagic zone (0–100 m), these orders occurred at similar abundance levels, whereas in the meso- and bathypelagic zones the poecilostomatoid genus Oncaea dominated numerically by about 60–80% of all copepodids.The species diversity of Oncaea in the Red Sea is compared with preliminary results from the two adjacent regions. In the deep Eastern Mediterranean Sea, the number of species appears to be similar to that in the deep Red Sea and low as compared to the deep Arabian Sea. In this latter area an extremely speciose Oncaea fauna was found at depth below the oxygen-minimum-zone (900–1850 m). The results are related to the differences in the hydrographic conditions of these 3 areas.     

Morphology and molecules reveal two new species of Porites (Scleractinia,Poritidae) from the Red Sea and the Gulf of Aden

Two new reef coral species, Porites farasani sp. nov. and Porites hadramauti sp. nov. (Scleractinia, Poritidae), are described from the Red Sea and the Gulf of Aden. Porites farasani sp. nov. only occurs in the Farasan Islands in the southern Red Sea, while P. hadramauti sp. nov. has been collected in the Yemen Hadramaut region in the Gulf of Aden. Both species presented striking in situ differences with respect to other Porites species, and were characterized by small encrusting colonies and unusual polyp colouration. In order to test the genetic distinctiveness of P. farasani sp. nov. and P. hadramauti sp. nov. between each other and with respect to other representatives in the genus Porites, we investigated their evolutionary relationships with eight other morphological species of Porites occurring in the Red Sea and in the Gulf of Aden. Two DNA loci, the mitochondrial putative control region and the nuclear ribosomal ITS region, were sequenced, and three species delimitation approaches based on barcoding threshold (Automated Barcoding Gap Discovery) and coalescence theory (Poisson-Tree process, Generalized Mixed Yule Coalescent) were applied. Phylogenetic and species delimitation analyses were overall concordant, resolving P. farasani sp. nov. and P. hadramauti sp. nov. as two divergent but closely related lineages. Of the other morphologically defined Porites species, three were genetically differentiated (P. rus, P. columnaris and P. fontanesii), but five were genetically indistinguishable. The discovery of two regional endemics confirms the importance of the Red Sea and the Gulf of Aden as regions of high biodiversity and suggests the need for an integration of genome-wide molecular data with the re-evaluation of skeletal structures in the systematics of Porites.     

Morphological and genetic analysis of the Red Hills roach (Cyprinidae: Lavinia symmetricus)

We performed a morphological and phylogeneticanalysis of a recently discovered population ofCalifornia roach (Red Hills roach; Cyprinidae:Lavinia symmetricus) to determine if thedegree of separation of these populationswarrants subspecies status. Previousmorphological analysis by Brown et al. (1992)suggested that L. symmetricus from theRed Hills roach type locality (Horton Creek)were different for Principal DiscriminantScores (based on 15 morphological characters)from neighboring populations. Similarly,recent work by our lab on the phylogenetics ofthe putative subspecies of L. symmetricushas revealed that the Red Hills roach appearsreciprocally monophyletic for assayedmitochondrial DNA markers. In addition toperforming further morphological and geneticanalysis of the Red Hills roach, we increasedour sampling effort in the Red Hills region todetermine the distribution of this undescribedputative subspecies. Our morphological resultsare generally in agreement with Brown et al.(1992) except in regards to Horton Creek. Asignificant difference between the two studiesexists for all Horton Creek multivariateanalyses as well as frequency of a presumablyderived character (chisel lip). Our geneticresults also support our previous findings thatthe Red Hills roach is a diagnosible,genetically distinct population. Thephylogenetic analysis suggests that populationson the other side of a large reservoir wererecently connected via gene flow to the RedHills populations.     

Schindleria parva,a new species of Schindler's fish (Teleostei: Schindleriidae: Schindleria) from Jeddah,Saudi Arabia,Red Sea

Schindleria parva, a new species of the family Schindleriidae, is described from two specimens collected from the central Red Sea of Saudi Arabia. The new species is characterized by lack of pigmentation on the body, possession of an inconspicuous gas bladder and the presence of small teeth on the premaxillae. The holotype is a female of 11 mm standard length (SL) (11.9 mm total length) and the paratype is a male of 9 mm SL. Dorsal fin rays 10 (9) anal fin rays 9 (7). The body depth at pectoral-fin origin 5% (4%) of SL, depth at anal-fin origin 8% (7%) SL, predorsal length 63% (65%) SL, preanal length 72% (72%) SL, the first anal-fin ray situated below the fourth dorsal-fin ray), a total of 23 + 16 myomeres. The female contained a series of 30 rectangular eggs in a single row, whereas the male is characterized by a short rod-like urogenital papilla. Species of the genus Schindleria are likely the smallest marine vertebrates on the planet and S. parva is likely the smallest Schindleria species in the Red Sea. The global diversity of Schindleria is likely underestimated due to the paedomorphic features of this genus. Its fast generation times make it a species-rich genus of high turnover rates, thus potentially highly important for the trophic food webs of coral reefs. Thus, this finding advances knowledge on the biodiversity of the Red Sea, highlights its conservation significance, and contributes towards the understanding of the complexity of the coral-reef fish community.     

Being green in the Red Sea - the photosymbiotic ascidian Diplosoma simile (Ascidiacea: Didemnidae) in the Gulf of Aqaba

The photosymbiotic ascidian Diplosoma simile is characterized by a wide global distribution. The current study provides the first record of D. simile in the Red Sea, with remarks on its spatial distribution and phylogeny. Partial COI and 18S rDNA sequences of D. simile from the Red Sea revealed high similarity to those from the West Pacific, indicating a much broader range than previously recorded. In the Red Sea D. simile is common on natural coral reefs at depths ranging from 1–35 m. Diplosoma simile colonies were found to overgrow and would appear to suffocate several species of live stony corals, though this does not appear to cause mass coral mortality in the Red Sea, unlike that recorded in other locations.     

First record of the blackfin coral goby,Paragobiodon lacunicolus (Kendall and Goldsborough, ), from the Red Sea

Three specimens of the blackfin coral goby, Paragobiodon lacunicolus, were collected in 2010 and 2011 at different locations of the eastern Red Sea along the coast of Saudi Arabia. Reexamination of 14 museum specimens from Eritrea also confirmed the presence of the species for the western Red Sea. This represents the first published report of P. lacunicolus from the Red Sea.     

Genetic diversity and life-history traits of bonefish Albula spp. from the Red Sea

The management of bonefishes Albula spp. has been hindered by unresolved species distributions and a general lack of life-history information. This study provides the first genetic species identifications of Albula spp. from the northern Indian Ocean. The roundjaw bonefish Albula glossodonta was documented in the Red Sea, and the smallscale bonefish A. oligolepis was identified in the Gulf of Aden with no evidence supporting sympatry. Estimates of genetic differentiation indicate three closely related lineages of A. glossodonta in the Red Sea, Indian Ocean and Pacific Ocean (Red Sea-Pacific Ocean, F_st = 0.295; Red Sea-Seychelles, F_st = 0.193; Pacific Ocean-Seychelles, F_st = 0.141). In addition, the authors provide the first life-history information of Albula spp. in the Indian Ocean. Age-based growth models of A. glossodonta from the Red Sea demonstrated statistically significant differences compared to previously published data from the Pacific Ocean. Spawning activity during winter months was derived from gonado-somatic index values of A. glossodonta from the Red Sea and corresponded with spawning seasonality previously documented for the species in the Pacific Ocean. The results of this study aid in refining biogeographical uncertainties of Albula spp. and illustrate the importance of collecting regional growth information for subsequent management of A. glossodonta.     

Observations on the taxonomic composition and vertical distribution of cyclopoid copepods in the central Red Sea

The taxonomic composition and vertical distribution of cyclopoid copepods, including very small species, in the central Red Sea were analyzed. Samples were taken in a multiple opening and closing net with 0.1 mm mesh size to a depth of 450 m. Most species belong to the genus Oncaea (13 identified and 6 unidentified forms). Nearly one half of these are smaller than 0.4 mm in length. Nine cyclopoid species and three groups of very similar species and forms of Oncaea predominate. In the upper 450 m of the water column, each of these species or groups account for more than 1 % of all cyclopoid specimens. In the epipelagic zone (0–100 m) Oithona simplex predominates, accounting for 20 % of the total. In the upper mesopelagic zone Paroithona sp. and one of the unidentified Oncaea forms are most numerous from 100 to 250 m, and two groups of Oncaea are most abundant from 250 to 450 m. The dominance of single species among cyclopoids is less pronounced than that reported for calanoids in the mesopelagic zone of the central Red Sea.     

Behavioural and ultrastructural studies on the sedentary platyctenean ctenophore Vallicula multiformis

Feeding habit and diet composition of two colonizing mullids, Upeneus asymmetricus and U. moluccensis, and two indigenous goatfish Mullus barbatus and M. surmuletus (Mullidae), in the eastern Mediterranean were investigated. The most important taxonomic group in the diet of all four species was the Decapoda which were identified to the specific level, enabling precise assessment of trophic partitioning. Leptochela pugnax, a pasiphaeid of Red Sea origin, was by far the most important prey of all mullids studied, which resulted in considerable trophic overlap between all of the species. Trophic separation does not play an important role in resource partitioning of the eastern Mediterranean mullids. Consequently, coexistence between colonizing and indigenous mullids is presumably achieved by spatial segregation.     

Multi‐locus sequence data reveal a new species of coral reef goby (Teleostei: Gobiidae: Eviota), and evidence of Pliocene vicariance across the Coral Triangle

Here, multi‐locus sequence data are coupled with observations of live colouration to recognize a new species, Eviota punyit from the Coral Triangle, Indian Ocean and Red Sea. Relaxed molecular clock divergence time estimation indicates a Pliocene origin for the new species, and the current distribution of the new species and its sister species Eviota sebreei supports a scenario of vicariance across the Indo‐Pacific Barrier, followed by subsequent range expansion and overlap in the Coral Triangle. These results are consistent with the ‘centre of overlap’ hypothesis, which states that the increased diversity in the Coral Triangle is due in part to the overlapping ranges of Indian Ocean and Pacific Ocean faunas. These findings are discussed in the context of other geminate pairs of coral reef fishes separated by the Indo‐Pacific Barrier.     

Two <Emphasis Type="Italic">Pione</Emphasis> species (Hadromerida,Clionaidae) from the Red Sea: a taxonomical challenge

Boring sponges of the genus Pione (Hadromerida, Clionaidae) are easily recognizable due to their spiculation. However, species identification is challenging, as the potentially diagnostic morphological character states of different species often overlap. For this reason, this group of species is frequently referred to as the ‘Pione vastifica complex’, after the most well-studied species of the genus. Boring-sponge samples were collected in the Red Sea and identified as P. cf. lampa and P. cf. vastifica, respectively. So far, these two species names have usually been considered as valid, although some authors suggested them to be synonymous. Morphological analyses were performed on spicules and micro-erosion patterns by means of both light and scanning electron microscopy. Two apparent morphotypes can be distinguished, mainly by the growth form, but statistical analysis does not support a clear separation in two species. In addition, a DNA barcoding approach using sequences of CO1 has not identified any nucleotide sequence differences. These data support the hypothesis that P. cf. lampa and P. cf. vastifica from the Red Sea are conspecific.     

The littoral fish community of the Lebanese rocky coast (eastern Mediterranean Sea) with emphasis on Red Sea immigrants

The organisation of the coastal rocky fish community of Lebanon was investigated for the first time, using visual censuses. A total of 62 fish species were recorded between the surface and 32 m depth, 8 species being Red Sea migrants. Species richness and fish abundance were positively correlated first with substrate complexity and second with depth. The trophic structure of the community was dominated by diurnal zooplanktivores (Chromis chromis, Oblada melanura and Spicara smaris) and mesocarnivores 1 (Coris julis and Thalassoma pavo), and did not vary significantly with depth. The Lessepsian migrants represented 13% of the species richness and 19% of the total abundance of individuals. They dominated among herbivores, nocturnal zooplanktivores and macrocarnivores. The Lessepsian Siganus luridus and S. rivulatus (Siganidae), Pempheris vanicolensis (Pempheridae) and Sargocentron rubrum (Holocentridae) were now among the most common fish species on the Lebanese rocky coast. Lessepsian fish species displayed either similar ecological niches in the Red Sea and in the Levantine basin (P. vanicolensis, S. rubrum) or an enlargement of their depth distribution towards deeper waters in their new environment (S. luridus, S. rivulatus). This study will serve as a baseline for future studies as eastern Mediterranean communities are subjected to a steady increase in Red Sea migrant species.     

Highly restricted gene flow and deep evolutionary lineages in the giant clam <Emphasis Type="Italic">Tridacna maxima</Emphasis>

The tropical Indo-West Pacific is the biogeographic region with the highest diversity of marine shallow water species, with its centre in the Indo-Malay Archipelago. However, due to its high endemism, the Red Sea is also considered as an important centre of evolution. Currently, not much is known about exchange among the Red Sea, Indian Ocean and West Pacific, as well as connectivity within the Indo-Malay Archipelago, even though such information is important to illuminate ecological and evolutionary processes that shape marine biodiversity in these regions. In addition, the inference of connectivity among populations is important for conservation. This study aims to test the hypothesis that the Indo-Malay Archipelago and the Red Sea are important centres of evolution by studying the genetic population structure of the giant clam Tridacna maxima. This study is based on a 484-bp fragment of the cytochrome c oxidase I gene from 211 individuals collected at 14 localities in the Indo-West Pacific to infer lineage diversification and gene flow as a measure for connectivity. The analysis showed a significant genetic differentiation among sample sites in the Indo-West Pacific (Φ_st = 0.74, P < 0.001) and across the Indo-Malay Archipelago (Φ_st = 0.72, P < 0.001), indicating restricted gene flow. Hierarchical AMOVA revealed the highest fixation index (Φ_ct = 0.8, P < 0.001) when sample sites were assigned to the following regions: (1) Red Sea, (2) Indian Ocean and Java Sea, (3) Indonesian throughflow and seas in the East of Sulawesi, and (4) Western Pacific. Geological history as well as oceanography are important factors that shape the genetic structure of T. maxima in the Indo-Malay Archipelago and Red Sea. The observed deep evolutionary lineages might include cryptic species and this result supports the notion that the Indo-Malay Archipelago and the Red Sea are important centres of evolution. Communicated by Biology Editor Dr. Ruth Gates     

First record of Pristipomoides multidens (Day, 1871) from the Gulf of Aqaba,with a note on the species of Pristipomoides in the Red Sea (Actinopterygii: Lutjanidae)

The snapper Pristipomoides multidens is reported for the first time from the Gulf of Aqaba. A comparison of mitochondrial cytochrome oxidase subunit 1 (COI) with available data revealed a high similarity with a sample from Mauritius and a lower similarity with samples from the China Sea. The status and distribution of the Red Sea species of Pristipomoides are summarised.