Distribution and environmental control of coral assemblages in northern Safaga Bay (Red Sea, Egypt)

Summary Coral assemblages in northern Safaga Bay, Red Sea, Egypt, are qualitatively described. Nine distinct assemblages were found, which correspond to quantitatively defined community types previously described from the area off Hurghada, northern Red Sea. Their distribution within northern Safaga Bay was mapped. Strong gradient and/or steep relief assemblages were:Acropora assemblage on windward (exposed) reefs,Porites assemblage on leeward (sheltered) reefs,Millepora assemblage on current exposed reefs,Stylophora assemblage on reef flats. Low gradient and/or low relief assemblages were:Acropora dominated coral patches in areas of good circulation to a depth of 15 m,Stylophora/Acropora coral patch assemblages in shallow sheltered environments, faviid carpet in low relief areas between 10 and 25 m which with increasing turbidity turns into a depauperate faviid carpet,Porites carpet in low relief areas between 5 and 15 m with clearest water,Sarcophyton carpet in low relief areas with high suspension load, platy scleractinian assemblage in deeper water (>25 m) with low light intensity. The distribution of coral assemblages depends basically on 1) topography 2) hydrodynamics 3) light and 4) suspension load.     

Benthic foraminiferal associations in the Northern Bay of Safaga, Red Sea, Egypt

In the shallow-water area (0–70 m) of the Northern Bay of Safaga, 73 surface samples were studied with respect to total foraminiferal fauna. The samples cover a great variety of shallow-water environments and yielded 239 foraminiferal taxa. Based on q-mode cluster analysis, and tested by canonical discriminant analysis, the samples are grouped into 13 foraminiferal associations, each characterized by several species:

(1) Quinqueloculina mosharrafai-Borelis schlumbergeri-Brizalina simpsoni Ass.,

(2) Heterostegina depressa-Amphlstegina lessonii/bicirculata Ass.,

(3) Cibicidids-Rosalina-Amphistegina lobifera-Pseudoschlumbergerina ovata Ass.,

(4) Peneroplis planatus Ass.,

(5) Peneroplis planatus-Varidentella neostriatula Ass.,

(6) Peneroplis planatus-Coscinospira hemprichii-Varidentella neostriatula Ass.,

(7) Quinqueloculina spp. Ass.,

(8) Hauerina diversa-Sorites orbiculus Ass.,

(9) Verneuilina sp.-n Articulina pacifica-Reussella simplex Ass.,

(10) Textularia agglutinans/rugulosa-Bolivina variabilis Ass.,

(11) Textularia agglutinans-Challengerella bradyi-Elphidium jenseni/simplex Ass.,

(12) Operculina ammonoides-Adelosina laevigata-Brizalina striatula/subspathulata Ass.,

(13) Bolivina variabilis—Miliolinella-Nonion fabum-Elphidium simplex Ass.

The characteristic forms of each association are linked to specific environmental parameters and modes of life. As long as taxonomic uniformitarianism can be applied, similar associations with comparable ecological demands may also be detected in the fossil record. For comparisons with taxonomically different material the 13 associations are summarized into 4 categories each reflecting a specific type of substrate. In the fossil record these categories may be recognized by general morphological characteristics of the foraminiferal tests and by sedimentological data. The 4 substrate types are: hardground, sand (with or without seagrass and/or corals), firmground, and soft bottom.     

Bivalve distribution on coral carpets in the Northern Bay of Safaga (Red Sea, Egypt) and its relation to environmental parameters

Summary Bivalve assemblages on coral carpets in the Northern Bay of Safaga do not form distinct associations, but gradually shift in faunal composition. The taxonomic shift is accompanied by continuous variations in bivalve density and percentage of living individuals as well as by a change of coral associations and potential bivalve habitats. The gradual lateral change of associations is best documented byTridacna maxima and jewel box clams (Chamoidea) and is probably due to variations of the suspension load in the water column. High suspension loads in the water column are additionally indicated by ‘giant oysters’ (extremely large individuals ofHyotissa hyotis) and striking agglomerates ofLopha cristagalli. The vertical differentiation is best documented by the decrease of the zooxanthellateTridacna maxima and is probably due to the depth-dependent light penetration in the water column, which is attenuated in areas of high suspension load.     

Distribution of recent foraminiferal assemblages near the Ombrone River mouth (Northern Tyrrhenian Sea, Italy)

Benthic foraminiferal assemblages in 127 samples, collected at water depth, ranging between 15 and 184 m on the Southern Tuscany continental shelf off the Ombrone River were analysed. Statistical analyses (Cluster and Principal Component Analysis) performed on the 48 most abundant species (>5%) and sedimentological data led to the identification of three clusters related to the size of grain sediment (sand, silt or clay). Q-mode cluster analysis singled out six groups, corresponding to six distinct foraminiferal assemblages: a typical infralittoral assemblage (15-39 m) on sandy silt, clayey silt or silty clay, dominated by Ammonia and Elphidium species, with Eggerelloides scabrus, Rectuvigerina phlegeri and Valvulineria bradyana; a second assemblage (24-78.5 m) associated with vegetated environments or sandy bottoms (Elphidium crispum, Rosalina bradyi, Asterigerinata mamilla, Neoconorbina terquemi, and Tretomphalus concinnus); a third assemblage recognised between 30 and 90 m water depth and characterised by the dominance of the opportunistic species V. bradyana (related to silty bottoms), with Bulimina marginata, R. phlegeri, Ammonia inflata and Ammonia beccarii as other common taxa; an upper circalittoral assemblage (70-100 m) on silty clays, containing B. marginata, Cassidulina carinata and V. bradyana; a lower circalittoral assemblage (95-177 m) on clayey bottoms, with B. marginata, Textularia bocki and Uvigerina mediterranea; and finally, a second lower circalittoral assemblage (104-184 m) on clayey sediments, dominated by two Uvigerina species (U. mediterranea and Uvigerina peregrina), with Sphaeroidina bulloides and B. marginata. The typical V. bradyana assemblage, characterised by relatively low diversity and high dominance, marks the most eutrophicated area running parallel to the coast. The spatial distribution of assemblages is closely associated with sea-bottom sedimentary environments and bathymetry but it is also probably influenced by the outflow of the Ombrone River. The composition, structure and distribution of V. bradyana assemblage suggest an environmental model, useful for paleogeographic reconstruction in areas characterised by a river mouth and a closed morphological setting typical of a nutrient-trap.     

Bryozoa from northern Red Sea,Egypt: 1 Crisia (Cyclostomata)

Seventy-five bryozoan species were picked from shallow bottom sediments (0–33 m depths) at five sites in the northern Red Sea: El Fanader, Hurghada Harbour, Makkadi Bay, Al Qweh Lagoon and El-Humrawen. Crisia specimens (Cyclostomata) are common and exhibit different variations. Six species were recognised among the specimens collected: Crisia eburnea (Linnaeus), Crisia elongata (Milne-Edwards), Crisia hornesi Reuss, Crisia sertularoides (Audouin), Crisia tenuis MacGillivray and Crisia hurghadaensis n. sp. The present paper deals with these Crisia species; other bryozoan taxa recovered will be published later. Biogeographic study reveals that three of these species are cosmopolitan, and represented by common to abundant occurrences (C. elongata, C. eburnea and C. hornesi). Two species are local endemics, and represented by only rare occurrences (C. sertularoides and C. hurghadaensis n. sp.). One species (C. tenuis) is Indo-Pacific, and is recorded here for the first time in equatorial waters.     

The palaeoecology of the micromammals from the late middle Pleistocene site of Hoedjiespunt 1 (Cape Province, South Africa)

The palaeontological site of Hoedjiespunt 1 (HDP1) represents a fossilized hyaena lair. A rich mammalian fauna, including four hominid teeth, has been recovered from the site. Micromammals were recovered from the same sediments as the larger fauna. Taphonomic analysis suggests that the micromammal assemblages from HDP1 were accumulated by a barn owl. The barn owl produces micromammal assemblages that provide a broad sample of micromammals, within a certain size range, living in the hunting area of the owl. There are size-related and other biases inherent in the prey selection of this predator, and owls may roost in one area and hunt in another however, the barn owl has frequently been found to provide a better indication of micromammals living within an area than trapping. The micromammals from HDP1 were used to reconstruct the microhabitats in the vicinity of the site. Two taxonomic habitat indexes were used to assess the environment and dominant habitat types at Hoedjiespunt 1. The variability and adaptability of many of the southern African micromammals complicates interpretation of the results, however, it appears that the micromammals from the HDP1 fossil assemblages utilized habitats of open, scrub vegetation, and rocky and sandy areas. It is suggested that the environment was not markedly different from today, but it may have been relatively more arid. A comparison between HDP1 and other fossil sites in the area dating from the terminal Pleistocene to the Holocene indicates that HDP1 is lacking certain species that are common to all the other west coast fossil sites. There is some discrepancy in the environment indicated by the large mammals as compared that indicated by to the micromammals at the site. It is suggested that this discrepancy may reflect the fact that an owl is likely to have hunted in the vicinity of the hyaena den, probably in the more open areas around the roost site, whereas the macrofauna, accumulated by the further-ranging brown hyaena (Hyaena brunnea), represents environments from further afield.     

Carbonate production by scleractinian corals at Aqaba,Gulf of Aqaba,Red Sea

Summary In a fringing reef at Aqaba at the northern end of the Gulf of Aqaba (29°26′N) growth rates, density, and the calcification rate ofPorites were investigated in order to establish calculations of gross carbonate production for the reefs in this area. Colony accretion ofPorites decreases with depth as a function of decreasing growth rates. The calcification rate ofPorites is highest in shallow water (0–5 m depth) with 0.9 g·cm⁻²·yr⁻¹ and falls down to 0.5 g·cm⁻²·yr⁻¹ below 30 m. Scleractinian coral gross production is calculated from potential productivity and coral coverage. It is mainly dependent on living coral cover and to a lesser extent on potential productivity. Total carbonate production on the reef ranged from 0 to 2.7 kg/m² per year, with a reef-wide average of 1.6 kg/m² perycar. Maximum gross carbonate production by corals at Aqaba occurs at the reef crest and in the middle fore-reef from 10 to 15 m water depth. Production is low in sandy reef parts. Below 30 m depth values still reach ca. 50% of shallow water values. Mean potential production of colonies and gross carbonate production of the whole reef community at Aqaba is lower than in tropical reefs. However, carbonate production is higher than in reef areas at the same latitude in the Pacific, indicating a northward shift of reef production in the Red Sea.     

The fossil record and taphonomy of butterflies and moths (Insecta,Lepidoptera): implications for evolutionary diversity and divergence-time estimates

Background

It is conventionally accepted that the lepidopteran fossil record is significantly incomplete when compared to the fossil records of other, very diverse, extant insect orders. Such an assumption, however, has been based on cumulative diversity data rather than using alternative statistical approaches from actual specimen counts.

Results

We reviewed documented specimens of the lepidopteran fossil record, currently consisting of 4,593 known specimens that are comprised of 4,262 body fossils and 331 trace fossils. The temporal distribution of the lepidopteran fossil record shows significant bias towards the late Paleocene to middle Eocene time interval. Lepidopteran fossils also record major shifts in preservational style and number of represented localities at the Mesozoic stage and Cenozoic epoch level of temporal resolution. Only 985 of the total known fossil specimens (21.4%) were assigned to 23 of the 40 extant lepidopteran superfamilies. Absolute numbers and proportions of preservation types for identified fossils varied significantly across superfamilies. The secular increase of lepidopteran family-level diversity through geologic time significantly deviates from the general pattern of other hyperdiverse, ordinal-level lineages.

Conclusion

Our statistical analyses of the lepidopteran fossil record show extreme biases in preservation type, age, and taxonomic composition. We highlight the scarcity of identified lepidopteran fossils and provide a correspondence between the latest lepidopteran divergence-time estimates and relevant fossil occurrences at the superfamily level. These findings provide caution in interpreting the lepidopteran fossil record through the modeling of evolutionary diversification and in determination of divergence time estimates.

Electronic supplementary material

The online version of this article (doi:10.1186/s12862-015-0290-8) contains supplementary material, which is available to authorized users.     

Population status of giant clams (Mollusca: Tridacnidae) in the northern Red Sea,Egypt

Throughout their range, giant clams (family Tridacnidae) are increasingly threatened by anthropogenic impacts and natural disasters, but little is known about their population status. In this first assessment of the tridacnid population at Abu Sauatir in the northern Red Sea, a total of 491 m² were surveyed and >200 clams recorded. Tridacna maxima was the only species found. The population's live:dead ratio was 3:1. Overall clam density was 0.08?±?0.008 live and 0.02?±?0.007 dead individuals per 0.25 m². Greatest densities occurred on the reef flat in 1 m depth (live), and on the northern reef slope in deeper waters (dead). On the slope, live clam density decreased significantly, whereas dead clam density increased significantly with depth. Sizes of live and dead individuals differed significantly. Live clams ranged from 1 to 30 cm (median 5 cm). Juveniles ≤2 cm (8.2% of the population) and individuals >11 cm occurred on the reef slope but not on the reef flat. Live clam sizes did not differ significantly between reef sites. Dead clam size ranged from 2 to 15 cm (median 6.5 cm). 2.1% of the empty shells were ≤2 cm long. Dead clam sizes differed significantly between 5 and 10 m depth on the northern reef slope. The low clam abundance (live and dead) in the shallowest and most easily accessible areas of the reef flat, combined with small sizes, strongly suggest artisanal reef-top gathering for meat and shells.     

Taphonomy of larger foraminifera: Relationships between living individuals and empty tests on flat reef slopes (Sesoko Island, Japan)

Summary The depth distributions of larger foraminifera (27 species) were investigated along two transects in the fore reef areas of a NW Pacific fringing reef. One transect is distinguished by a strong flattening below the steep reef slope (−30 m), whereas further steepening characterizes the equivalent part in the other transect. According to the different taphonomic processes affecting foraminiferal tests before final sedimentation, empty tests were classified into the three categories ‘optimally’, ‘well’ and ‘poorly’ preserved. The depth distribution of each preservation state was compared with living individuals. While distributions of optimally preserved tests almost coincide with living individuals, well-preserved tests are characterized by significant depth shifts that are stronger at the upper-most slope compared with the deeper parts. Since the time-averaged traction forces are similar in both investigated transects, differences between the distributions of living individuals and well-preserved tests are more intensive on steep versus flat slopes. Poorly preserved tests signalize allochthonous origin or reworking of relict sediments.     

Record of an Indo-Pacific humpback dolphin (Sousa chinensis) without its upper rostrum in Xiamen Bay,Fujian Province,China

Many cetaceans are killed as a result of intensive anthropogenic impacts, and those that survive often endure wounds or scars. This study is the first report of an Indo-Pacific humpback dolphin (Sousa chinensis) that is missing its upper rostrum. This individual has inhabited Xiamen Bay, Fujian Province, China, for more than 3 years. Since the lower jaw and the other part around the upper jaw are intact, it is likely that the upper jaw was entangled in fishing nets or pipelines and subsequently broke off. Without the upper rostrum, this dolphin cannot snap prey, but it may use other feeding strategies – and the fact that this individual has survived for more than 3 years without its upper rostrum provides a novel insight into the ability of this species to persist in the wild.     

Transgressive facies sequence of a high energy,wave-tide-storm-influenced shoreface: A case study of the east Frisian Barrier Islands (Southern North Sea)

Summary Published information and recent observation of physical and biogenic structures as well as grain size patterns along the East Frisian barrier islands (southern North Sea) have been synthesized to develop a facies model for a high energy, wave-tide-storm-influenced transgressive shoreface. As exemplified by Spiekeroog Island, three major shoreface facies (Upper, Central and Lower) are distinguishable, each of which can be subdivided into a Proximal and a Distal subfacies. A transgressive shoreface sequence in the rock record, in ascending order, will show the Upper Shoreface facies (USF) at the base. This is characterized by very well-sorted fine sands exhibiting predominantly plane lamination, which is consistent with its wave-dominated flow regime. The Central Shoreface facies (CSF) overlying the USF shows a high proportion of shells, a broad range of sediment sizes (fine sand to pebbles), and marked diversity in sedimentary structures. Graded storm beds, tidal cross-strata, mud-sand couplets, and horizontal to subhorizontal lamination are common. Swaley/hummocky (?) strata may also occur in its Distal subfacies. The sequence is topped by the Lower Shoreface facies (LSF). It consists mostly of bioturbated fine sands, although graded beds do occur. Distal sabfacies sands are consistently finer, better sorted, and more positively skewed than their Proximal counterpart. Anomalies in both coastwise and cross-shore textural trends are noted. In contrast to most other coastal settings, both fair-weather (wave- and tidal-current) and storm deposits are likely to be represented in subequal proportion in the rock record.     

Orientation of crustacean burrows in the Bay of Panzano (Gulf of Trieste, Northern Adriatic Sea)

Three burrow systems produced by Jaxea nocturna and one cluster of burrows produced by Upogebia pusilla where investigated in the Bay of Panzano, Northern Adriatic Sea, to determine preferred orientations. The distributions of dip directions differ between both producers. Steep shafts into the consolidated mud followed by large, shallowly inclined tunnels oriented in a manner similar to a spiral are characteristic for Jaxea nocturna burrows. In contrast, the Y-shaped burrows of Upogebia pusilla have entrance shafts that are less steep which are connected by a near-horizontal section, where a blind ending tunnel branches. Orientations of the dominating, shallowly inclined burrow parts are not randomly distributed in either Jaxea or in Upogebia burrows. Three preferred axial orientations with almost equal proportions in each direction are characteristic for the Jaxea burrow from the centre of the bay. This system transforms to a squared structure near the coast, where one direction parallels the shoreline and the other is oriented at right angles to the coast. The latter orientation demonstrates significant constancy in all investigated burrows. Upogebia burrow clusters coincide with the three preferred orientations of the Jaxea burrow from the bay centre, but the proportions of the directions are unequal. Burrow segments connecting the steep entrance shafts in Upogebia are oriented almost parallel to the shoreline, whereas at right angles to the coast the flat blind-ending tunnels incline towards the open sea. The study shows a strong coincidence between empirical and theoretical distributions of the dominating orientations in both species.     

Orientation of crustacean burrows in the Bay of Panzano (Gulf of Trieste, Northern Adriatic Sea)

Three burrow systems produced by Jaxea nocturna and one cluster of burrows produced by Upogebia pusilla where investigated in the Bay of Panzano, Northern Adriatic Sea, to determine preferred orientations. The distributions of dip directions differ between both producers. Steep shafts into the consolidated mud followed by large, shallowly inclined tunnels oriented in a manner similar to a spiral are characteristic for Jaxea nocturna burrows. In contrast, the Y-shaped burrows of Upogebia pusilla have entrance shafts that are less steep which are connected by a near-horizontal section, where a blind ending tunnel branches. Orientations of the dominating, shallowly inclined burrow parts are not randomly distributed in either Jaxea or in Upogebia burrows. Three preferred axial orientations with almost equal proportions in each direction are characteristic for the Jaxea burrow from the centre of the bay. This system transforms to a squared structure near the coast, where one direction parallels the shoreline and the other is oriented at right angles to the coast. The latter orientation demonstrates significant constancy in all investigated burrows. Upogebia burrow clusters coincide with the three preferred orientations of the Jaxea burrow from the bay centre, but the proportions of the directions are unequal. Burrow segments connecting the steep entrance shafts in Upogebia are oriented almost parallel to the shoreline, whereas at right angles to the coast the flat blind-ending tunnels incline towards the open sea. The study shows a strong coincidence between empirical and theoretical distributions of the dominating orientations in both species.     

Multi-annual changes in the parasite communities of rabbitfish Siganus rivulatus (Siganidae) in the Gulf of Aqaba, Red Sea

The parasite communities of the rabbitfish, Siganus rivulatus, were used to track multi-annual changes in the northern Gulf of Aqaba, Red Sea, in an environment subjected to ongoing anthropogenic impact. Parasitological data from these fish were collected from 1998 to 2000, with spring and fall samplings at three locations: at a coral reef (OBS), at a sandy beach area (NB) and at a mariculture cage farm (FF). These data were compared with data from 1995–1997 as well as data collected during 1981–1985 at the coral reef sampling site. The data analyses indicate that the ratio between heteroxenous and monoxenous parasite species declined significantly at all sites between 1995–1997 and 1998–2000. During the same period, the species richness of monoxenous parasites increased significantly at all sites. The species richness of heteroxenous parasites decreased significantly at the coral reef site, but remained steady at the other two sites. This coincided with a significant increase in the prevalence of monogeneans at the OBS and FF sites and a significant decrease in the prevalence of digeneans at the FF and NB sites. The decline in the abundance of the latter, specifically of Opisthogonoporoides sp. and Gyliauchen sp., was even more significant when compared with the 1981–1985 data. The prevalence of other gut helminths, namely the digenean Hexangium sigani and the nematodes Cucullanus sigani and Procamallanus elatensis, however, showed a significant increase over the same period. Analysis of the species richness and diversity indices of the parasite communities did not reveal conspicuous differences. These, however, did become apparent when heteroxenous and monoxenous members of particular taxa were analyzed separately. Therefore, when using parasite assemblages to detect ecological changes, it is essential to analyze not only at the community level, but also to consider separate components of particular parasitic groups. Communicated by H. von Westernhagen, A. Diamant     

The ontogeny of appendages and carapace of Neonesidea schulzi (Ostracoda: Bairdiidae) from the Red Sea coast,Egypt

The ostracod genus Neonesidea is broadly distributed in shallow marine waters. The ontogeny of the N. schulzi (Bairdiidae) is described in detail by studying the development of the appendages and variations in carapace form, size and structure. Neonesidea schulzi has eight post-embryonic instars, and a gap in its ontogenetic development during instar A-6, where no new Anlage is added. The Anlagen of the copulatory organs and the forked terminal claw of second antenna appear in the seventh (A-1) instar, and the first thoracic legs of podocopid ostracods are shown to descend from the thoracic region. For the first time in ostracods, observations of moulting from sixth and seventh instars are presented.     

Epilithozoan fauna associated with ferromanganese crustgrounds on the continental slope segment between Capri and Li Galli Islands (Bay of Salerno, Northern Tyrrhenian Sea, Italy)

The epilithozoan fauna associated with Quaternary Fe–Mn crustgrounds sampled off Capri and Li Galli Islands is described. During the Quaternary, the interplay among the tectonically induced topography, sea-current patterns, and the changing physical-chemical properties of the water column promoted conditions favouring Fe–Mn oxide accumulation. In the samples dredged between 510–263 m depth (DRA 7), 207–201 m depth (DRA 5) and 358–65 m depth (DRA 4), where the Fe–Mn coating covers all rock surfaces, the distribution of the epilithozoan taxa is polarized: on the upper smooth surface of the crustgrounds the most abundant inhabitants are foraminifers, while on the lower rough surface corals, bivalves, bryozoans and brachiopods occur. Sponges are mainly able to bioerode the rough lower surfaces. Samples are riddled by boring ichnogenera including Entobia and Maeandropolydora. Fe–Mn oxide precipitation is still active today as shown by the frontal shield preservation of the bryozoan Puellina cf. pseudoradiata Harmelin and Aristegui, 1988, where it is possible to identify different stages of accretion. Botryoidal ongoing accretion is evident only in some taxa, namely Bryozoa and Polychaeta species, and Foraminifera morphotypes, which appear to keep pace with precipitation when it occurs.     

The Meroplankton of Amurskii Bay (Peter the Great Bay,Sea of Japan)

Russian Journal of Marine Biology - The composition and seasonal dynamics of meroplankton in Amurskii Bay (Sea of Japan) were studied for the first time. The total survey period exceeded two years....     

Patterns and changes of reef-coral communities at the Sanganeb-Atoll (Sudan,central Red Sea): 1980 to 1991

Summary Benthic coral reef communities were investigated on the Sanganeb-Atoll, 28 km off the coast of Port Sudan (Sudan, central Red Sea). Four test areas (5×5 m) were selected and marked in approx. 10 m depth along a transect running in SSW-NNE direction over the atoll and were mapped in 1980 and 1991. Detailed photographs were used for in situ verification of taxonomic composition of communities (comprising some 135 cnidarian species) and transferred to scale 1∶10 maps, used for the quantitative analyses of coral communities in the test areas. Shares of inanimate (unoccupied) substrate were 42–60% of the total test areas in 1991 (i.e. slightly larger than at the 1980 census). The living cover was mainly composed of scleractinian and alcyonacean species. Coral communities were analysed on the species level with regard to taxonomic composition, areal coverage, biophysiographic zonation, and changes in community structures during the investigation period of 11 years. The analyses revealed a general constancy in the overall composition and distribution of benthic taxa which reflect the different abiotic conditions along the transect across the leeward and windward sides of the atoll. However, the detailed view on species recruitment, growth, decrease and disappearance on the base of a decadal time span allows to detect life history traints of stony and soft corals and their significance for the dynamics of the respective communities. Especially soft corals (predominating in the two leeward test quadrats) exhibit various strategies to colonize and occupy space. Their presence, however, is hardly to be detected from the fossil record (except for spiculite of some Sinularia spp.). Exemplarity, single colonies' fates were reconstructed and extrapolated. Based on the data of species recruitment and disappearance a time estimate for development and turnover of reef communities is provided. Species turnover rates were calculated as approx. 15 species/10 years (T_rel=2.63%/year) with estimated median community turnover periods of 416 (323–755) years from recruitment rates, or 338 (219–526) years from clearing rates. Data reference: This study is based on extensive datasets compiled in five appendices (referred to as “App.” in the text) which can be viewed and/or downloaded from the internet site at: www.meeresmuseum.de/sciencedata/facies-sanganeb.pdf. “If the biota, in the course of aeons, has built something we like but do not understand, then who but a fool would disregard seemingly useless parts? To keep every cog and wheel is the first precaution of intelligent tinkering.” Aldo Leopold, A Sand Country Almanac, 1949